Add parser module

doesn't work yet

.gitignore

@@ -1,4 +1,3 @@
 target
-.schala_repl
-.schala_history
-rusty-tags.vi
+node_modules/
+experiments/tree-sitter-test/src

Cargo.toml

@@ -1,18 +1,7 @@
-[package]
-name = "schala"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-
-[dependencies]
-
-schala-repl = { path = "schala-repl" }
-schala-lang = { path = "schala-lang/language" }
-partis = { path="partis" }
-# maaru-lang = { path = "maaru" }
-# rukka-lang = { path = "rukka" }
-# robo-lang = { path = "robo" }
-
-[build-dependencies]
-includedir_codegen = "0.2.0"
-
 [workspace]
+members = [
+    "schala-main",
+    "schala-parser",
+    "experiments",
+]
+resolver = "2"

HindleyMilner.hs

@@ -1,920 +0,0 @@
-{-# LANGUAGE GeneralizedNewtypeDeriving #-}
-{-# LANGUAGE LambdaCase                 #-}
-{-# LANGUAGE OverloadedLists            #-}
-{-# LANGUAGE OverloadedStrings          #-}
-
-
-
--- | This module is an extensively documented walkthrough for typechecking a
--- basic functional language using the Hindley-Damas-Milner algorithm.
---
--- In the end, we'll be able to infer the type of expressions like
---
--- @
--- find (λx. (>) x 0)
---   :: [Integer] -> Either () Integer
--- @
---
--- It can be used in multiple different forms:
---
---  * The source is written in literate programming style, so you can almost
---    read it from top to bottom, minus some few references to later topics.
---  * /Loads/ of doctests (runnable and verified code examples) are included
---  * The code is runnable in GHCi, all definitions are exposed.
---  * A small main module that gives many examples of what you might try out in
---    GHCi is also included.
---  * The Haddock output yields a nice overview over the definitions given, with
---    a nice rendering of a truckload of Haddock comments.
-
-module HindleyMilner where
-
-import           Control.Monad.Trans
-import           Control.Monad.Trans.Except
-import           Control.Monad.Trans.State
-import           Data.Map                   (Map)
-import qualified Data.Map                   as M
-import           Data.Monoid
-import           Data.Set                   (Set)
-import qualified Data.Set                   as S
-import           Data.String
-import           Data.Text                  (Text)
-import qualified Data.Text                  as T
-
-
-
--- $setup
---
--- For running doctests:
---
--- >>> :set -XOverloadedStrings
--- >>> :set -XOverloadedLists
--- >>> :set -XLambdaCase
--- >>> import qualified Data.Text.IO as T
--- >>> let putPprLn = T.putStrLn . ppr
-
-
-
--- #############################################################################
--- #############################################################################
--- * Preliminaries
--- #############################################################################
--- #############################################################################
-
-
-
--- #############################################################################
--- ** Prettyprinting
--- #############################################################################
-
-
-
--- | A prettyprinter class. Similar to 'Show', but with a focus on having
--- human-readable output as opposed to being valid Haskell.
-class Pretty a where
-    ppr :: a -> Text
-
-
-
--- #############################################################################
--- ** Names
--- #############################################################################
-
-
-
--- | A 'name' is an identifier in the language we're going to typecheck.
--- Variables on both the term and type level have 'Name's, for example.
-newtype Name = Name Text
-    deriving (Eq, Ord, Show)
-
--- | >>> "lorem" :: Name
--- Name "lorem"
-instance IsString Name where
-    fromString = Name . T.pack
-
--- | >>> putPprLn (Name "var")
--- var
-instance Pretty Name where
-    ppr (Name n) = n
-
-
-
--- #############################################################################
--- ** Monotypes
--- #############################################################################
-
-
-
--- | A monotype is an unquantified/unparametric type, in other words it contains
--- no @forall@s. Monotypes are the inner building blocks of all types. Examples
--- of monotypes are @Int@, @a@, @a -> b@.
---
--- In formal notation, 'MType's are often called τ (tau) types.
-data MType = TVar Name           -- ^ @a@
-           | TFun MType MType    -- ^ @a -> b@
-           | TConst Name         -- ^ @Int@, @()@, …
-
-           -- Since we can't declare our own types in our simple type system
-           -- here, we'll hard-code certain basic ones so we can typecheck some
-           -- familar functions that use them later.
-           | TList MType         -- ^ @[a]@
-           | TEither MType MType -- ^ @Either a b@
-           | TTuple MType MType  -- ^ @(a,b)@
-           deriving Show
-
--- | >>> putPprLn (TFun (TEither (TVar "a") (TVar "b")) (TFun (TVar "c") (TVar "d")))
--- Either a b → c → d
---
--- Using the 'IsString' instance:
---
--- >>> putPprLn (TFun (TEither "a" "b") (TFun "c" "d"))
--- Either a b → c → d
-instance Pretty MType where
-    ppr = go False
-      where
-        go _ (TVar name)   = ppr name
-        go _ (TList a)     = "[" <> ppr a <> "]"
-        go _ (TEither l r) = "Either " <> ppr l <> " " <> ppr r
-        go _ (TTuple a b)  = "(" <> ppr a <> ", " <> ppr b <> ")"
-        go _ (TConst name) = ppr name
-        go parenthesize (TFun a b)
-            | parenthesize = "(" <> lhs <> " → " <> rhs <> ")"
-            | otherwise    =        lhs <> " → " <> rhs
-            where lhs = go True a
-                  rhs = go False b
-
--- | >>> "var" :: MType
--- TVar (Name "var")
-instance IsString MType where
-    fromString = TVar . fromString
-
-
-
--- | The free variables of an 'MType'. This is simply the collection of all the
--- individual type variables occurring inside of it.
---
--- __Example:__ The free variables of @a -> b@ are @a@ and @b@.
-freeMType :: MType -> Set Name
-freeMType = \case
-    TVar a      -> [a]
-    TFun a b    -> freeMType a <> freeMType b
-    TList a     -> freeMType a
-    TEither l r -> freeMType l <> freeMType r
-    TTuple a b  -> freeMType a <> freeMType b
-    TConst _    -> []
-
-
-
--- | Substitute all the contained type variables mentioned in the substitution,
--- and leave everything else alone.
-instance Substitutable MType where
-    applySubst s = \case
-        TVar a -> let Subst s' = s
-                  in M.findWithDefault (TVar a) a s'
-        TFun f x    -> TFun (applySubst s f) (applySubst s x)
-        TList a     -> TList (applySubst s a)
-        TEither l r -> TEither (applySubst s l) (applySubst s r)
-        TTuple a b  -> TTuple (applySubst s a) (applySubst s b)
-        c@TConst {} -> c
-
-
-
--- #############################################################################
--- ** Polytypes
--- #############################################################################
-
--- | A polytype is a monotype universally quantified over a number of type
--- variables. In Haskell, all definitions have polytypes, but since the @forall@
--- is implicit they look a bit like monotypes, maybe confusingly so. For
--- example, the type of @1 :: Int@ is actually @forall <nothing>. Int@, and the
--- type of @id@ is @forall a. a -> a@, although GHC displays it as @a -> a@.
---
--- A polytype claims to work "for all imaginable type parameters", very similar
--- to how a lambda claims to work "for all imaginable value parameters". We can
--- insert a value into a lambda's parameter to evaluate it to a new value, and
--- similarly we'll later insert types into a polytype's quantified variables to
--- gain new types.
---
--- __Example:__ in a definition @id :: forall a. a -> a@, the @a@ after the
--- ∀ ("forall") is the collection of type variables, and @a -> a@ is the 'MType'
--- quantified over. When we have such an @id@, we also have its specialized
--- version @Int -> Int@ available. This process will be the topic of the type
--- inference/unification algorithms.
---
--- In formal notation, 'PType's are often called σ (sigma) types.
---
--- The purpose of having monotypes and polytypes is that we'd like to only have
--- universal quantification at the top level, restricting our language to rank-1
--- polymorphism, where type inferece is total (all types can be inferred) and
--- simple (only a handful of typing rules). Weakening this constraint would be
--- easy: if we allowed universal quantification within function types we would
--- get rank-N polymorphism. Taking it even further to allow it anywhere,
--- effectively replacing all occurrences of 'MType' with 'PType', yields
--- impredicative types. Both these extensions make the type system
--- *significantly* more complex though.
-data PType = Forall (Set Name) MType -- ^ ∀{α}. τ
-
--- | >>> putPprLn (Forall ["a"] (TFun "a" "a"))
--- ∀a. a → a
-instance Pretty PType where
-    ppr (Forall qs mType) = "∀" <> pprUniversals <> ". " <> ppr mType
-      where
-        pprUniversals
-          | S.null qs = "∅"
-          | otherwise = (T.intercalate " " . map ppr . S.toList) qs
-
-
-
--- | The free variables of a 'PType' are the free variables of the contained
--- 'MType', except those universally quantified.
---
--- >>> let sigma = Forall ["a"] (TFun "a" (TFun (TTuple "b" "a") "c"))
--- >>> putPprLn sigma
--- ∀a. a → (b, a) → c
--- >>> let display = T.putStrLn . T.intercalate ", " . foldMap (\x -> [ppr x])
--- >>> display (freePType sigma)
--- b, c
-freePType :: PType -> Set Name
-freePType (Forall qs mType) = freeMType mType `S.difference` qs
-
-
-
--- | Substitute all the free type variables.
-instance Substitutable PType where
-    applySubst (Subst subst) (Forall qs mType) =
-        let qs' = M.fromSet (const ()) qs
-            subst' = Subst (subst `M.difference` qs')
-        in Forall qs (applySubst subst' mType)
-
-
-
--- #############################################################################
--- ** The environment
--- #############################################################################
-
-
-
--- | The environment consists of all the values available in scope, and their
--- associated polytypes. Other common names for it include "(typing) context",
--- and because of the commonly used symbol for it sometimes directly
--- \"Gamma"/@"Γ"@.
---
--- There are two kinds of membership in an environment,
---
---   - @∈@: an environment @Γ@ can be viewed as a set of @(value, type)@ pairs,
---     and we can test whether something is /literally contained/ by it via
---     x:σ ∈ Γ
---   - @⊢@, pronounced /entails/, describes all the things that are well-typed,
---     given an environment @Γ@. @Γ ⊢ x:τ@ can thus be seen as a judgement that
---     @x:τ@ is /figuratively contained/ in @Γ@.
---
--- For example, the environment @{x:Int}@ literally contains @x@, but given
--- this, it also entails @λy. x@, @λy z. x@, @let id = λy. y in id x@ and so on.
---
--- In Haskell terms, the environment consists of all the things you currently
--- have available, or that can be built by comining them. If you import the
--- Prelude, your environment entails
---
--- @
--- id            →  ∀a. a→a
--- map           →  ∀a b. (a→b) → [a] → [b]
--- putStrLn      →  ∀∅. String → IO ()
--- …
--- id map        →  ∀a b. (a→b) → [a] → [b]
--- map putStrLn  →  ∀∅. [String] -> [IO ()]
--- …
--- @
-newtype Env = Env (Map Name PType)
-
--- | >>> :{
---    putPprLn (Env
---        [ ("id", Forall ["a"] (TFun "a" "a"))
---        , ("const", Forall ["a", "b"] (TFun "a" (TFun "b" "a"))) ])
--- :}
--- Γ = { const : ∀a b. a → b → a
---     , id : ∀a. a → a }
-instance Pretty Env where
-    ppr (Env env) = "Γ = { " <> T.intercalate "\n    , " pprBindings <> " }"
-      where
-        bindings = M.assocs env
-        pprBinding (name, pType) = ppr name <> " : " <> ppr pType
-        pprBindings = map pprBinding bindings
-
-
-
--- | The free variables of an 'Env'ironment are all the free variables of the
--- 'PType's it contains.
-freeEnv :: Env -> Set Name
-freeEnv (Env env) = let allPTypes = M.elems env
-                    in S.unions (map freePType allPTypes)
-
-
-
--- | Performing a 'Subst'itution in an 'Env'ironment means performing that
--- substituion on all the contained 'PType's.
-instance Substitutable Env where
-    applySubst s (Env env) = Env (M.map (applySubst s) env)
-
-
-
--- #############################################################################
--- ** Substitutions
--- #############################################################################
-
-
-
--- | A substitution is a mapping from type variables to 'MType's. Applying a
--- substitution means applying those replacements. For example, the substitution
--- @a -> Int@ applied to @a -> a@ yields the result @Int -> Int@.
---
--- A key concept behind Hindley-Milner is that once we dive deeper into an
--- expression, we learn more about our type variables. We might learn that  @a@
--- has to be specialized to @b -> b@, and then later on that @b@ is actually
--- @Int@. Substitutions are an organized way of carrying this information along.
-newtype Subst = Subst (Map Name MType)
-
-
-
--- | We're going to apply substitutions to a variety of other values that
--- somehow contain type variables, so we overload this application operation in
--- a class here.
---
--- Laws:
---
--- @
--- 'applySubst' 'mempty' ≡ 'id'
--- 'applySubst' (s1 '<>' s2) ≡ 'applySubst' s1 . 'applySubst' s2
--- @
-class Substitutable a where
-    applySubst :: Subst -> a -> a
-
-instance (Substitutable a, Substitutable b) => Substitutable (a,b) where
-    applySubst s (x,y) = (applySubst s x, applySubst s y)
-
--- | @'applySubst' s1 s2@ applies one substitution to another, replacing all the
--- bindings in the second argument @s2@ with their values mentioned in the first
--- one (@s1@).
-instance Substitutable Subst where
-    applySubst s (Subst target) = Subst (fmap (applySubst s) target)
-
--- | >>> :{
---    putPprLn (Subst
---        [ ("a", TFun "b" "b")
---        , ("b", TEither "c" "d") ])
--- :}
--- { a ––> b → b
--- , b ––> Either c d }
-instance Pretty Subst where
-    ppr (Subst s) = "{ " <> T.intercalate "\n, " [ ppr k <> " ––> " <> ppr v | (k,v) <- M.toList s ] <> " }"
-
--- | Combine two substitutions by applying all substitutions mentioned in the
--- first argument to the type variables contained in the second.
-instance Monoid Subst where
-    -- Considering that all we can really do with a substitution is apply it, we
-    -- can use the one of 'Substitutable's laws to show that substitutions
-    -- combine associatively,
-    --
-    -- @
-    --   applySubst (compose s1 (compose s2 s3))
-    -- = applySubst s1 . applySubst (compose s2 s3)
-    -- = applySubst s1 . applySubst s2 . applySubst s3
-    -- = applySubst (compose s1 s2) . applySubst s3
-    -- = applySubst (compose (compose s1 s2) s3)
-    -- @
-    mappend subst1 subst2 = Subst (s1 `M.union` s2)
-      where
-        Subst s1 = subst1
-        Subst s2 = applySubst subst1 subst2
-
-    mempty = Subst M.empty
-
-
-
--- #############################################################################
--- #############################################################################
--- * Typechecking
--- #############################################################################
--- #############################################################################
-
--- $ Typechecking does two things:
---
--- 1. If two types are not immediately identical, attempt to 'unify' them
---    to get a type compatible with both of them
--- 2. 'infer' the most general type of a value by comparing the values in its
---    definition with the 'Env'ironment
-
-
-
--- #############################################################################
--- ** Inference context
--- #############################################################################
-
-
-
--- | The inference type holds a supply of unique names, and can fail with a
--- descriptive error if something goes wrong.
---
--- /Invariant:/ the supply must be infinite, or we might run out of names to
--- give to things.
-newtype Infer a = Infer (ExceptT InferError (State [Name]) a)
-    deriving (Functor, Applicative, Monad)
-
--- | Errors that can happen during the type inference process.
-data InferError =
-    -- | Two types that don't match were attempted to be unified.
-    --
-    -- For example, @a -> a@ and @Int@ do not unify.
-    --
-    -- >>> putPprLn (CannotUnify (TFun "a" "a") (TConst "Int"))
-    -- Cannot unify a → a with Int
-      CannotUnify MType MType
-
-    -- | A 'TVar' is bound to an 'MType' that already contains it.
-    --
-    -- The canonical example of this is @λx. x x@, where the first @x@
-    -- in the body has to have type @a -> b@, and the second one @a@. Since
-    -- they're both the same @x@, this requires unification of @a@ with
-    -- @a -> b@, which only works if @a = a -> b = (a -> b) -> b = …@, yielding
-    -- an infinite type.
-    --
-    -- >>> putPprLn (OccursCheckFailed "a" (TFun "a" "a"))
-    -- Occurs check failed: a already appears in a → a
-    | OccursCheckFailed Name MType
-
-    -- | The value of an unknown identifier was read.
-    --
-    -- >>> putPprLn (UnknownIdentifier "a")
-    -- Unknown identifier: a
-    | UnknownIdentifier Name
-    deriving Show
-
--- | >>> putPprLn (CannotUnify (TEither "a" "b") (TTuple "a" "b"))
--- Cannot unify Either a b with (a, b)
-instance Pretty InferError where
-    ppr = \case
-        CannotUnify t1 t2 ->
-            "Cannot unify " <> ppr t1 <> " with " <> ppr t2
-        OccursCheckFailed name ty ->
-            "Occurs check failed: " <> ppr name <> " already appears in " <> ppr ty
-        UnknownIdentifier name ->
-            "Unknown identifier: " <> ppr name
-
-
-
--- | Evaluate a value in an 'Infer'ence context.
---
--- >>> let expr = EAbs "f" (EAbs "g" (EAbs "x" (EApp (EApp "f" "x") (EApp "g" "x"))))
--- >>> putPprLn expr
--- λf g x. f x (g x)
--- >>> let inferred = runInfer (infer (Env []) expr)
--- >>> let demonstrate = \case Right (_, ty) -> T.putStrLn (":: " <> ppr ty)
--- >>> demonstrate inferred
--- :: (c → e → f) → (c → e) → c → f
-runInfer :: Infer a -- ^ Inference data
-         -> Either InferError a
-runInfer (Infer inf) =
-    evalState (runExceptT inf) (map Name (infiniteSupply alphabet))
-  where
-
-    alphabet = map T.singleton ['a'..'z']
-
-    -- [a, b, c] ==> [a,b,c, a1,b1,c1, a2,b2,c2, …]
-    infiniteSupply supply = supply <> addSuffixes supply (1 :: Integer)
-      where
-        addSuffixes xs n = map (\x -> addSuffix x n) xs <> addSuffixes xs (n+1)
-        addSuffix x n = x <> T.pack (show n)
-
-
-
--- | Throw an 'InferError' in an 'Infer'ence context.
---
--- >>> case runInfer (throw (UnknownIdentifier "var")) of Left err -> putPprLn err
--- Unknown identifier: var
-throw :: InferError -> Infer a
-throw = Infer . throwE
-
-
-
--- #############################################################################
--- ** Unification
--- #############################################################################
-
--- $ Unification describes the process of making two different types compatible
--- by specializing them where needed. A desirable property to have here is being
--- able to find the most general unifier. Luckily, we'll be able to do that in
--- our type system.
-
-
-
--- | The unification of two 'MType's is the most general substituion that can be
--- applied to both of them in order to yield the same result.
---
--- >>> let m1 = TFun "a" "b"
--- >>> putPprLn m1
--- a → b
--- >>> let m2 = TFun "c" (TEither "d" "e")
--- >>> putPprLn m2
--- c → Either d e
--- >>> let inferSubst = unify (m1, m2)
--- >>> case runInfer inferSubst of Right subst -> putPprLn subst
--- { a ––> c
--- , b ––> Either d e }
-unify :: (MType, MType) -> Infer Subst
-unify = \case
-    (TFun a b,    TFun x y)          -> unifyBinary (a,b) (x,y)
-    (TVar v,      x)                 -> v `bindVariableTo` x
-    (x,           TVar v)            -> v `bindVariableTo` x
-    (TConst a,    TConst b) | a == b -> pure mempty
-    (TList a,     TList b)           -> unify (a,b)
-    (TEither a b, TEither x y)       -> unifyBinary (a,b) (x,y)
-    (TTuple a b,  TTuple x y)        -> unifyBinary (a,b) (x,y)
-    (a, b)                           -> throw (CannotUnify a b)
-
-  where
-
-    -- Unification of binary type constructors, such as functions and Either.
-    -- Unification is first done for the first operand, and assuming the
-    -- required substitution, for the second one.
-    unifyBinary :: (MType, MType) -> (MType, MType) -> Infer Subst
-    unifyBinary (a,b) (x,y) = do
-        s1 <- unify (a, x)
-        s2 <- unify (applySubst s1 (b, y))
-        pure (s1 <> s2)
-
-
-
--- | Build a 'Subst'itution that binds a 'Name' of a 'TVar' to an 'MType'. The
--- resulting substitution should be idempotent, i.e. applying it more than once
--- to something should not be any different from applying it only once.
---
--- - In the simplest case, this just means building a substitution that just
---   does that.
--- - Substituting a 'Name' with a 'TVar' with the same name unifies a type
---   variable with itself, and the resulting substitution does nothing new.
--- - If the 'Name' we're trying to bind to an 'MType' already occurs in that
---   'MType', the resulting substitution would not be idempotent: the 'MType'
---   would be replaced again, yielding a different result. This is known as the
---   Occurs Check.
-bindVariableTo :: Name -> MType -> Infer Subst
-
-bindVariableTo name (TVar v) | boundToSelf = pure mempty
-  where
-    boundToSelf = name == v
-
-bindVariableTo name mType | name `occursIn` mType = throw (OccursCheckFailed name mType)
-  where
-    n `occursIn` ty = n `S.member` freeMType ty
-
-bindVariableTo name mType = pure (Subst (M.singleton name mType))
-
-
-
--- #############################################################################
--- ** Type inference
--- #############################################################################
-
--- $ Type inference is the act of finding out a value's type by looking at the
--- environment it is in, in order to make it compatible with it.
---
--- In literature, the Hindley-Damas-Milner inference algorithm ("Algorithm W")
--- is often presented in the style of logical formulas, and below you'll find
--- that version along with code that actually does what they say.
---
--- These formulas look a bit like fractions, where the "numerator" is a
--- collection of premises, and the denominator is the consequence if all of them
--- hold.
---
--- __Example:__
---
--- @
--- Γ ⊢ even : Int → Bool   Γ ⊢ 1 : Int
--- –––––––––––––––––––––––––––––––––––
---          Γ ⊢ even 1 : Bool
--- @
---
--- means that if we have a value of type @Int -> Bool@ called "even" and a value
--- of type @Int@ called @1@, then we also have a value of type @Bool@ via
--- @even 1@ available to us.
---
--- The actual inference rules are polymorphic versions of this example, and
--- the code comments will explain each step in detail.
-
-
-
--- -----------------------------------------------------------------------------
--- *** The language: typed lambda calculus
--- -----------------------------------------------------------------------------
-
-
-
--- | The syntax tree of the language we'd like to typecheck. You can view it as
--- a close relative to simply typed lambda calculus, having only the most
--- necessary syntax elements.
---
--- Since 'ELet' is non-recursive, the usual fixed-point function
--- @fix : (a → a) → a@ can be introduced to allow recursive definitions.
-data Exp = ELit Lit          -- ^ True, 1
-         | EVar Name         -- ^ @x@
-         | EApp Exp Exp      -- ^ @f x@
-         | EAbs Name Exp     -- ^ @λx. e@
-         | ELet Name Exp Exp -- ^ @let x = e in e'@ (non-recursive)
-         deriving Show
-
-
-
--- | Literals we'd like to support. Since we can't define new data types in our
--- simple type system, we'll have to hard-code the possible ones here.
-data Lit = LBool Bool
-         | LInteger Integer
-         deriving Show
-
-
-
--- | >>> putPprLn (EAbs "f" (EAbs "g" (EAbs "x" (EApp (EApp "f" "x") (EApp "g" "x")))))
--- λf g x. f x (g x)
-instance Pretty Exp where
-    ppr (ELit lit) = ppr lit
-
-    ppr (EVar name) = ppr name
-
-    ppr (EApp f x) = pprApp1 f <> " " <> pprApp2 x
-      where
-        pprApp1 = \case
-            eLet@ELet{} -> "(" <> ppr eLet <> ")"
-            eLet@EAbs{} -> "(" <> ppr eLet <> ")"
-            e -> ppr e
-        pprApp2 = \case
-            eApp@EApp{} -> "(" <> ppr eApp <> ")"
-            e -> pprApp1 e
-
-    ppr x@EAbs{} = pprAbs True x
-      where
-        pprAbs True  (EAbs name expr) = "λ" <> ppr name <> pprAbs False expr
-        pprAbs False (EAbs name expr) = " " <> ppr name <> pprAbs False expr
-        pprAbs _ expr                 = ". " <> ppr expr
-
-    ppr (ELet name value body) =
-        "let " <> ppr name <> " = " <> ppr value <> " in " <> ppr body
-
--- | >>> putPprLn (LBool True)
--- True
---
--- >>> putPprLn (LInteger 127)
--- 127
-instance Pretty Lit where
-    ppr = \case
-        LBool    b -> showT b
-        LInteger i -> showT i
-      where
-        showT :: Show a => a -> Text
-        showT = T.pack . show
-
--- | >>> "var" :: Exp
--- EVar (Name "var")
-instance IsString Exp where
-    fromString = EVar . fromString
-
-
-
--- -----------------------------------------------------------------------------
--- *** Some useful definitions
--- -----------------------------------------------------------------------------
-
-
-
--- | Generate a fresh 'Name' in a type 'Infer'ence context. An example use case
--- of this is η expansion, which transforms @f@ into @λx. f x@, where "x" is a
--- new name, i.e. unbound in the current context.
-fresh :: Infer MType
-fresh = drawFromSupply >>= \case
-    Right name -> pure (TVar name)
-    Left err -> throw err
-
-  where
-
-    drawFromSupply :: Infer (Either InferError Name)
-    drawFromSupply = Infer (do
-        s:upply <- lift get
-        lift (put upply)
-        pure (Right s) )
-
-
-
--- | Add a new binding to the environment.
---
--- The Haskell equivalent would be defining a new value, for example in module
--- scope or in a @let@ block. This corresponds to the "comma" operation used in
--- formal notation,
---
--- @
--- Γ, x:σ  ≡  extendEnv Γ (x,σ)
--- @
-extendEnv :: Env -> (Name, PType) -> Env
-extendEnv (Env env) (name, pType) = Env (M.insert name pType env)
-
-
-
--- -----------------------------------------------------------------------------
--- *** Inferring the types of all language constructs
--- -----------------------------------------------------------------------------
-
-
-
--- | Infer the type of an 'Exp'ression in an 'Env'ironment, resulting in the
--- 'Exp's 'MType' along with a substitution that has to be done in order to reach
--- this goal.
---
--- This is widely known as /Algorithm W/.
-infer :: Env -> Exp -> Infer (Subst, MType)
-infer env = \case
-    ELit lit    -> inferLit lit
-    EVar name   -> inferVar env name
-    EApp f x    -> inferApp env f x
-    EAbs x e    -> inferAbs env x e
-    ELet x e e' -> inferLet env x e e'
-
-
-
--- | Literals such as 'True' and '1' have their types hard-coded.
-inferLit :: Lit -> Infer (Subst, MType)
-inferLit lit = pure (mempty, TConst litTy)
-  where
-    litTy = case lit of
-        LBool    {} -> "Bool"
-        LInteger {} -> "Integer"
-
-
-
--- | Inferring the type of a variable is done via
---
--- @
--- x:σ ∈ Γ   τ = instantiate(σ)
--- ––––––––––––––––––––––––––––  [Var]
---            Γ ⊢ x:τ
--- @
---
--- This means that if @Γ@ /literally contains/ (@∈@) a value, then it also
--- /entails it/ (@⊢@) in all its instantiations.
-inferVar :: Env -> Name -> Infer (Subst, MType)
-inferVar env name = do
-    sigma <- lookupEnv env name -- x:σ ∈ Γ
-    tau <- instantiate sigma    -- τ = instantiate(σ)
-                                -- ------------------
-    pure (mempty, tau)          -- Γ ⊢ x:τ
-
-
-
--- | Look up the 'PType' of a 'Name' in the 'Env'ironment.
---
--- This checks whether @x:σ@ is /literally contained/ in @Γ@. For more details
--- about this, see the documentation of 'Env'.
---
--- To give a Haskell analogon, looking up @id@ when @Prelude@ is loaded, the
--- resulting 'PType' would be @id@'s type, namely @forall a. a -> a@.
-lookupEnv :: Env -> Name -> Infer PType
-lookupEnv (Env env) name = case M.lookup name env of
-    Just x  -> pure x
-    Nothing -> throw (UnknownIdentifier name)
-
-
-
--- | Bind all quantified variables of a 'PType' to 'fresh' type variables.
---
--- __Example:__ instantiating @forall a. a -> b -> a@ results in the 'MType'
--- @c -> b -> c@, where @c@ is a fresh name (to avoid shadowing issues).
---
--- You can picture the 'PType' to be the prototype converted to an instantiated
--- 'MType', which can now be used in the unification process.
---
--- Another way of looking at it is by simply forgetting which variables were
--- quantified, carefully avoiding name clashes when doing so.
---
--- 'instantiate' can also be seen as the opposite of 'generalize', which we'll
--- need later to convert an 'MType' to a 'PType'.
-instantiate :: PType -> Infer MType
-instantiate (Forall qs t) = do
-    subst <- substituteAllWithFresh qs
-    pure (applySubst subst t)
-
-  where
-    -- For each given name, add a substitution from that name to a fresh type
-    -- variable to the result.
-    substituteAllWithFresh :: Set Name -> Infer Subst
-    substituteAllWithFresh xs = do
-        let freshSubstActions = M.fromSet (const fresh) xs
-        freshSubsts <- sequenceA freshSubstActions
-        pure (Subst freshSubsts)
-
-
-
--- | Function application captures the fact that if we have a function and an
--- argument we can give to that function, we also have the result value of the
--- result type available to us.
---
--- @
--- Γ ⊢ f : fτ   Γ ⊢ x : xτ   fxτ = fresh   unify(fτ, xτ → fxτ)
--- –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  [App]
---                       Γ ⊢ f x : fxτ
--- @
---
--- This rule says that given a function and a value with a type, the function
--- type has to unify with a function type that allows the value type to be its
--- argument.
-inferApp
-    :: Env
-    -> Exp -- ^ __f__ x
-    -> Exp -- ^ f __x__
-    -> Infer (Subst, MType)
-inferApp env f x = do
-    (s1, fTau) <- infer env f                         -- f : fτ
-    (s2, xTau) <- infer (applySubst s1 env) x         -- x : xτ
-    fxTau <- fresh                                    -- fxτ = fresh
-    s3 <- unify (applySubst s2 fTau, TFun xTau fxTau) -- unify (fτ, xτ → fxτ)
-    let s = s3 <> s2 <> s1                            -- --------------------
-    pure (s, applySubst s3 fxTau)                     -- f x : fxτ
-
-
-
--- | Lambda abstraction is based on the fact that when we introduce a new
--- variable, the resulting lambda maps from that variable's type to the type of
--- the body.
---
--- @
--- τ = fresh   σ = ∀∅. τ   Γ, x:σ ⊢ e:τ'
--- –––––––––––––––––––––––––––––––––––––  [Abs]
---             Γ ⊢ λx.e : τ→τ'
--- @
---
--- Here, @Γ, x:τ@ is @Γ@ extended by one additional mapping, namely @x:τ@.
---
--- Abstraction is typed by extending the environment by a new 'MType', and if
--- under this assumption we can construct a function mapping to a value of that
--- type, we can say that the lambda takes a value and maps to it.
-inferAbs
-    :: Env
-    -> Name -- ^ λ__x__. e
-    -> Exp  -- ^ λx. __e__
-    -> Infer (Subst, MType)
-inferAbs env x e = do
-    tau <- fresh                           -- τ = fresh
-    let sigma = Forall [] tau              -- σ = ∀∅. τ
-        env' = extendEnv env (x, sigma)    -- Γ, x:σ …
-    (s, tau') <- infer env' e              --        … ⊢ e:τ'
-                                           -- ---------------
-    pure (s, TFun (applySubst s tau) tau') -- λx.e : τ→τ'
-
-
-
--- | A let binding allows extending the environment with new bindings in a
--- principled manner. To do this, we first have to typecheck the expression to
--- be introduced. The result of this is then generalized to a 'PType', since let
--- bindings introduce new polymorphic values, which are then added to the
--- environment. Now we can finally typecheck the body of the "in" part of the
--- let binding.
---
--- Note that in our simple language, let is non-recursive, but recursion can be
--- introduced as usual by adding a primitive @fix : (a → a) → a@ if desired.
---
--- @
--- Γ ⊢ e:τ   σ = gen(Γ,τ)   Γ, x:σ ⊢ e':τ'
--- –––––––––––––––––––––––––––––––––––––––  [Let]
---         Γ ⊢ let x = e in e' : τ'
--- @
-inferLet
-    :: Env
-    -> Name -- ^ let __x__ = e in e'
-    -> Exp -- ^ let x = __e__ in e'
-    -> Exp -- ^ let x = e in __e'__
-    -> Infer (Subst, MType)
-inferLet env x e e' = do
-    (s1, tau) <- infer env e              -- Γ ⊢ e:τ
-    let env' = applySubst s1 env
-    let sigma = generalize env' tau       -- σ = gen(Γ,τ)
-    let env'' = extendEnv env' (x, sigma) -- Γ, x:σ
-    (s2, tau') <- infer env'' e'          -- Γ ⊢ …
-                                          -- --------------------------
-    pure (s2 <> s1, tau')                 --     … let x = e in e' : τ'
-
-
-
--- | Generalize an 'MType' to a 'PType' by universally quantifying over all the
--- type variables contained in it, except those already free in the environment.
---
--- >>> let tau = TFun "a" (TFun "b" "a")
--- >>> putPprLn tau
--- a → b → a
--- >>> putPprLn (generalize (Env [("x", Forall [] "b")]) tau)
--- ∀a. a → b → a
---
--- In more formal notation,
---
--- @
--- gen(Γ,τ) = ∀{α}. τ
---     where {α} = free(τ) – free(Γ)
--- @
---
--- 'generalize' can also be seen as the opposite of 'instantiate', which
--- converts a 'PType' to an 'MType'.
-generalize :: Env -> MType -> PType
-generalize env mType = Forall qs mType
-  where
-    qs = freeMType mType `S.difference` freeEnv env

Main.hs

@@ -1,185 +0,0 @@
-{-# LANGUAGE OverloadedLists   #-}
-{-# LANGUAGE OverloadedStrings #-}
-
-module Main where
-
-
-
-import qualified Data.Map     as M
-import           Data.Monoid
-import           Data.Text    (Text)
-import qualified Data.Text.IO as T
-
-import HindleyMilner
-
-
-
--- #############################################################################
--- #############################################################################
--- * Testing
--- #############################################################################
--- #############################################################################
-
-
-
--- #############################################################################
--- ** A small custom Prelude
--- #############################################################################
-
-
-
-prelude :: Env
-prelude = Env (M.fromList
-    [ ("(*)",        Forall []              (tInteger ~> tInteger ~> tInteger))
-    , ("(+)",        Forall []              (tInteger ~> tInteger ~> tInteger))
-    , ("(,)",        Forall ["a","b"]       ("a" ~> "b" ~> TTuple "a" "b"))
-    , ("(-)",        Forall []              (tInteger ~> tInteger ~> tInteger))
-    , ("(.)",        Forall ["a", "b", "c"] (("b" ~> "c") ~> ("a" ~> "b") ~> "a" ~> "c"))
-    , ("(<)",        Forall []              (tInteger ~> tInteger ~> tBool))
-    , ("(<=)",       Forall []              (tInteger ~> tInteger ~> tBool))
-    , ("(>)",        Forall []              (tInteger ~> tInteger ~> tBool))
-    , ("(>=)",       Forall []              (tInteger ~> tInteger ~> tBool))
-    , ("const",      Forall ["a","b"]       ("a" ~> "b" ~> "a"))
-    , ("Cont/>>=",   Forall ["a"]           ((("a" ~> "r") ~> "r") ~> ("a" ~> (("b" ~> "r") ~> "r")) ~> (("b" ~> "r") ~> "r")))
-    , ("find",       Forall ["a","b"]       (("a" ~> tBool) ~> TList "a" ~> tMaybe "a"))
-    , ("fix",        Forall ["a"]           (("a" ~> "a") ~> "a"))
-    , ("foldr",      Forall ["a","b"]       (("a" ~> "b" ~> "b") ~> "b" ~> TList "a" ~> "b"))
-    , ("id",         Forall ["a"]           ("a" ~> "a"))
-    , ("ifThenElse", Forall ["a"]           (tBool ~> "a" ~> "a" ~> "a"))
-    , ("Left",       Forall ["a","b"]       ("a" ~> TEither "a" "b"))
-    , ("length",     Forall ["a"]           (TList "a" ~> tInteger))
-    , ("map",        Forall ["a","b"]       (("a" ~> "b") ~> TList "a" ~> TList "b"))
-    , ("reverse",    Forall ["a"]           (TList "a" ~> TList "a"))
-    , ("Right",      Forall ["a","b"]       ("b" ~> TEither "a" "b"))
-    , ("[]",         Forall ["a"]           (TList "a"))
-    , ("(:)",        Forall ["a"]           ("a" ~> TList "a" ~> TList "a"))
-    ])
-  where
-    tBool = TConst "Bool"
-    tInteger = TConst "Integer"
-    tMaybe = TEither (TConst "()")
-
-
-
--- | Synonym for 'TFun' to make writing type signatures easier.
---
--- Instead of
---
--- @
--- Forall ["a","b"] (TFun "a" (TFun "b" "a"))
--- @
---
--- we can write
---
--- @
--- Forall ["a","b"] ("a" ~> "b" ~> "a")
--- @
-(~>) :: MType -> MType -> MType
-(~>) = TFun
-infixr 9 ~>
-
-
-
--- #############################################################################
--- ** Run it!
--- #############################################################################
-
-
-
--- | Run type inference on a cuple of values
-main :: IO ()
-main = do
-    let inferAndPrint = T.putStrLn . ("  " <>) . showType prelude
-    T.putStrLn "Well-typed:"
-    do
-        inferAndPrint (lambda ["x"] "x")
-        inferAndPrint (lambda ["f","g","x"] (apply "f" ["x", apply "g" ["x"]]))
-        inferAndPrint (lambda ["f","g","x"] (apply "f" [apply "g" ["x"]]))
-        inferAndPrint (lambda ["m", "k", "c"] (apply "m" [lambda ["x"] (apply "k" ["x", "c"])])) -- >>= for Cont
-        inferAndPrint (lambda ["f"] (apply "(.)" ["reverse", apply "map" ["f"]]))
-        inferAndPrint (apply "find" [lambda ["x"] (apply "(>)" ["x", int 0])])
-        inferAndPrint (apply "map" [apply "map" ["map"]])
-        inferAndPrint (apply "(*)" [int 1, int 2])
-        inferAndPrint (apply "foldr" ["(+)", int 0])
-        inferAndPrint (apply "map" ["length"])
-        inferAndPrint (apply "map" ["map"])
-        inferAndPrint (lambda ["x"] (apply "ifThenElse" [apply "(<)" ["x", int 0], int 0, "x"]))
-        inferAndPrint (lambda ["x"] (apply "fix" [lambda ["xs"] (apply "(:)" ["x", "xs"])]))
-    T.putStrLn "Ill-typed:"
-    do
-        inferAndPrint (apply "(*)" [int 1, bool True])
-        inferAndPrint (apply "foldr" [int 1])
-        inferAndPrint (lambda ["x"] (apply "x" ["x"]))
-        inferAndPrint (lambda ["x"] (ELet "xs" (apply "(:)" ["x", "xs"]) "xs"))
-
-
-
--- | Build multiple lambda bindings.
---
--- Instead of
---
--- @
--- EAbs "f" (EAbs "x" (EApp "f" "x"))
--- @
---
--- we can write
---
--- @
--- lambda ["f", "x"] (EApp "f" "x")
--- @
---
--- for
---
--- @
--- λf x. f x
--- @
-lambda :: [Name] -> Exp -> Exp
-lambda names expr = foldr EAbs expr names
-
-
-
--- | Apply a function to multiple arguments.
---
--- Instead of
---
--- @
--- EApp (EApp (EApp "f" "x") "y") "z")
--- @
---
--- we can write
---
--- @
--- apply "f" ["x", "y", "z"]
--- @
---
--- for
---
--- @
--- f x y z
--- @
-apply :: Exp -> [Exp] -> Exp
-apply = foldl EApp
-
-
-
--- | Construct an integer literal.
-int :: Integer -> Exp
-int = ELit . LInteger
-
-
-
--- | Construct a boolean literal.
-bool :: Bool -> Exp
-bool = ELit . LBool
-
-
-
--- | Convenience function to run type inference algorithm
-showType :: Env    -- ^ Starting environment, e.g. 'prelude'.
-         -> Exp    -- ^ Expression to typecheck
-         -> Text   -- ^ Text representation of the result. Contains an error
-                   --   message on failure.
-showType env expr =
-    case (runInfer . fmap (generalize (Env mempty) . uncurry applySubst) . infer env) expr of
-        Left err -> "Error inferring type of " <> ppr expr <>": " <> ppr err
-        Right ty -> ppr expr <> " :: " <> ppr ty

README.md

@@ -1,95 +1,4 @@
-# Schala - a programming language meta-interpreter
+# Schala - A Programming Language Implementation
 
-Schala is a Rust framework written to make it easy to create and experiment
-with multipl toy programming languages. It provides a cross-language REPL and
-provisions for tokenizing text, parsing tokens, evaluating an abstract syntax
-tree, and other tasks that are common to all programming languages, as well as sharing state
-between multiple programming languages.
-
-Schala is implemented as a Rust library `schala-repl`, which provides a
-function `start_repl`, meant to be used as entry point into a common REPL or
-non-interactive environment. Clients are expected to invoke `start_repl` with a
-vector of programming languages. Individual programming language
-implementations are Rust types that implement the
-`ProgrammingLanguageInterface` trait and store whatever persistent state is
-relevant to that language. 
-
-Run schala with: `cargo run`. This will drop you into a REPL environment.  Type
-`:help` for more information, or type in text in any supported programming
-language (currently only schala-lang) to evaluate it in the REPL.
-
-## History
-
-Schala started out life as an experiment in writing a Javascript-like
-programming language that would never encounter any kind of runtime value
-error, but rather always return `null` under any kind of error condition. I had
-seen one too many Javascript `Uncaught TypeError: Cannot read property ___ of
-undefined` messages, and I was a bit frustrated.  Plus I had always wanted to
-write a programming langauge from scratch, and Rust is a fun language to
-program in.  Over time I became interested in playing around with other sorts
-of programming languages as well, and wanted to make the process as general as
-possible.
-
-The name of the project comes from Schala the Princess of Zeal from the 1995
-SNES RPG *Chrono Trigger*. I like classic JRPGs and enjoyed the thought of
-creating a language name confusingly close to Scala. The naming scheme for
-languages implemented with the Schala meta-interpreter is Chrono Trigger
-characters.
-
-Schala and languages implemented with it are incomplete alpha software and are
-not ready for public release.
-
-## Languages implemented using the meta-interpreter
-
-* The eponymous *Schala* language is a work-in-progress general purpose
-  programming language with static typing and algebraic data types. Its design
-  goals include having a very straightforward implemenation and being syntactically
-  minimal.
-
-* *Maaru* is a very simple dynamically-typed scripting language, with the semantics
-    that all runtime errors return a `null` value rather than fail. 
-
-* *Robo* is an experiment in creating a lazy, functional, strongly-typed language
-much like Haskell
-
-* *Rukka* is a straightforward LISP implementation
-
-## Reference works
-
-Here's a partial list of resources I've made use of in the process
-of learning how to write a programming language.
-
-### General
-
-http://thume.ca/2019/04/18/writing-a-compiler-in-rust/
-
-### Type-checking
-https://skillsmatter.com/skillscasts/10868-inside-the-rust-compiler
-https://www.youtube.com/watch?v=il3gD7XMdmA
-http://dev.stephendiehl.com/fun/006_hindley_milner.html
-https://rust-lang-nursery.github.io/rustc-guide/type-inference.html
-
-https://eli.thegreenplace.net/2018/unification/
-https://eli.thegreenplace.net/2018/type-inference/
-http://smallcultfollowing.com/babysteps/blog/2017/03/25/unification-in-chalk-part-1/
-http://reasonableapproximation.net/2019/05/05/hindley-milner.html
-https://rickyhan.com/jekyll/update/2018/05/26/hindley-milner-tutorial-rust.html
-
-### Evaluation
-*Understanding Computation*, Tom Stuart, O'Reilly 2013
-
-*Basics of Compiler Design*, Torben Mogensen
-
-### Parsing
-http://journal.stuffwithstuff.com/2011/03/19/pratt-parsers-expression-parsing-made-easy/
-https://soc.github.io/languages/unified-condition-syntax
-
-[Crafting Interpreters](http://www.craftinginterpreters.com/)
-
-### LLVM
-http://blog.ulysse.io/2016/07/03/llvm-getting-started.html
-
-###Rust resources
-https://thefullsnack.com/en/rust-for-the-web.html
-
-https://rocket.rs/guide/getting-started/
+`schala` is an implementation of a yet-unnamed quasi-functional programming
+language.

TODO.md

@@ -1,178 +0,0 @@
-# Plan of attack
-
-1. modify visitor so it can handle scopes
-  -this is needed both to handle import scope correctly
-  -and also to support making FQSNs aware of function parameters
-
-2. Once FQSNs are aware of function parameters, most of the Rc<String> things in eval.rs can go away
-
-# TODO items
-
--use 'let' sigil in patterns for variables :
-
-```
-  q is MyStruct(let a, Chrono::Trigga) then {
-
-  }
-```
-
--idea: what if there was something like React jsx syntas built in? i.e. a way to automatically transform some kind of markup
-into a function call, cf. `<h1 prop="arg">` ->  h1(prop=arg)
-
-## General code cleanup
-- I think I can restructure the parser to get rid of most instances of expect!, at least at the beginning of a rule
-DONE -experiment with storing metadata via ItemIds on AST nodes (cf. https://rust-lang.github.io/rustc-guide/hir.html, https://github.com/rust-lang/rust/blob/master/src/librustc/hir/mod.rs )
--implement and test open/use statements
--implement field access
-- standardize on an error type that isn't String
--implement a visitor pattern for the use of scope_resolver
-  - maybe implement this twice: 1) the value-returning, no-default one in the haoyi blogpost,
-  -look at https://gitlab.haskell.org/ghc/ghc/wikis/pattern-synonyms
-                                2) the non-value-returning, default one like in rustc (cf. https://github.com/rust-unofficial/patterns/blob/master/patterns/visitor.md)
-
--parser error - should report subset of AST parsed *so far*
-  - what if you used python 'def' syntax to define a function? what error message makes sense here?
-
-## Reduction
- - make a good type for actual language builtins to avoid string comparisons
-
-## Typechecking
-
-- make a type to represent types rather than relying on string comparisons
-
-- look at https://rickyhan.com/jekyll/update/2018/05/26/hindley-milner-tutorial-rust.html
-
-- cf. the notation mentioned in the cardelli paper, the debug information for the `typechecking` pass should 
-print the generated type variable for every subexpression in an expression
-
-- think about idris-related ideas of multiple implementations of a type for an interface (+ vs * impl for monoids, for preorder/inorder/postorder for Foldable)
-
--should have an Idris-like `cast To From` function
-
-## Schala-lang syntax
-
--idea: the `type` declaration should have some kind of GADT-like syntax
-
-- Idea: if you have a pattern-match where one variant has a variable and the other lacks it
-instead of treating this as a type error, promote the bound variable to an option type
-
-- Include extensible scala-style html"string ${var}" string interpolations
-
-- A neat idea for pattern matching optimization would be if you could match on one of several things in a list
-ex:
-```if x {
- is (comp, LHSPat, RHSPat) if comp in ["==, "<"] -> ...
-}```
-
-- Schala should have both currying *and* default arguments!
-```fn a(b: Int, c:Int, d:Int = 1) -> Int
-    a(1,2) : Int
-    a(1,2,d=2): Int
-    a(_,1,3) : Int -> Int
-    a(1,2, c=_): Int -> Int
-    a(_,_,_) : Int -> Int -> Int -> Int
-```
-
-- scoped types - be able to define a quick enum type scoped to a function or other type for
-  something, that only is meant to be used as a quick bespoke interface between
-  two other things
-
-ex.
-```type enum {
-  type enum MySubVariant {
-    SubVariant1, SubVariant2, etc.
-    }
- Variant1(MySubVariant),
- Variant2(...),
- }```
-
-- inclusive/exclusive range syntax like .. vs ..=
-
-## Compilation
--look into Inkwell for rust LLVM bindings
-
--https://cranelift.readthedocs.io/en/latest/?badge=latest<Paste>
-
-
-## Other links of note
-
-- https://nshipster.com/never/
--consult http://gluon-lang.org/book/embedding-api.html
-
-
-## Trying if-syntax again
-
-//simple if expr
-if x == 10 then "a" else "z"
-
-//complex if expr
-if x == 10 then {
-  let a = 1
-  let b = 2
-  a + b
-} else {
-  55
-}
-
-// different comparison ops
-if x {
- == 1 then "a"
-  .isPrime() then "b"
-  else "c"
-}
-
-/* for now disallow `if x == { 1 then ... }`, b/c hard to parse
-
-//simple pattern-matching
-if x is Person("Ivan", age) then age else 0
-
-//match-block equivalent
-if x {
- is Person("Ivan", _) then "Ivan"
- is Person(_, age) if age > 13 then "barmitzvah'd"
- else "foo"
- }
-
-
-
-## (OLD) Playing around with conditional syntax ideas
-
-
-- if/match playground
-
-simple if
-`if x == 1.0 { "a" } else { "b" }`
-
-one comparison multiple targets:
-`if x == { 1.0 -> "a", 2.0 -> "b", else -> "c" }`
-
-different comparison operators/ method calls:
-`if x { == 1.0 -> "a", eq NaN -> "n", .hella() -> "h", else -> "z" }`
-
-pattern matching/introducing bindings:
-`if alice { .age < 18 -> "18", is Person("Alice", age) -> "${age}", else -> "none" }`
-
-pattern matching w/ if-let:
-`if person is Person("Alice", age) { "${age}" } else { "nope" }`
-
--https://soc.github.io/languages/unified-condition-syntax syntax:
-
-`if <cond-expr>" then <then-expr> else <else-expr>`
-`if <half-expr> \n <rest-expr1> then <result1-expr> \n <rest-expr2> then <result-expr2> else <result3-expr>`
--and rest-exprs (or "targets") can have 'is' for pattern-matching, actually so can a full cond-expr
-
-UNIFIED IF EXPRESSIONS FINAL WORK:
-
-basic syntax:
-
-`if_expr := if discriminator '{' (guard_expr)* '}'`
-`guard_expr := pattern 'then' block_or_expr'`
-`pattern := rhs | is_pattern`
-`is_pattern := 'is' ???`
-`rhs := expression | ???`
-
-
-if the only two guard patterns are true and false, then the abbreviated syntax:
-`'if' discriminator 'then' block_or_expr 'else' block_or_expr`
-can replace `'if' discriminator '{' 'true' 'then' block_or_expr; 'false' 'then' block_or_expr '}'`
-

experiments/Cargo.toml

@@ -1,8 +1,7 @@
 [package]
-name = "partis"
+name = "experiments"
 version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-edition = "2018"
+edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 

experiments/src/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!("Hello, world!");
+}

experiments/tree-sitter-test/grammar.js

@@ -0,0 +1,48 @@
+module.exports = grammar({
+    name: "TestLang",
+    rules: {
+        source_file: $ => repeat($._definition),
+
+        _definition: $ => choice(
+            $.function_definition
+            //TODO others
+        ),
+
+        function_definition: $ => seq(
+            'fn',
+            $.identifier,
+            $.parameter_list,
+            field("return_type", optional($._type)),
+            $.block,
+        ),
+        parameter_list: $ => seq("(", /* TODO */ ")"),
+
+        block: $ => seq(
+            "{",
+            choice(
+                repeat($._statement),
+                "",
+            ),
+            "}"
+        ),
+
+        _statement: $ => choice(
+            $._return_statement
+        ),
+
+        _return_statement: $ => seq("return", $._expression, ";"),
+
+        _expression: $ => choice($.identifier, $.unary, $.binary),
+
+        unary: $ => prec(4, choice(seq("-", $._expression), seq("!", $._expression))),
+        binary: $ => choice(prec.left(2, seq($._expression, "*", $._expression)), prec.left(1, seq($._expression, "+", $._expression))),
+
+        _type: $ => "bool",
+        _type: $ => choice(
+            $.primitive_type,
+        ),
+        primitive_type: $ => choice("bool", "int"),
+
+        identifier: $ => /[a-z]+/,
+    }
+});

experiments/tree-sitter-test/justfile

@@ -0,0 +1,8 @@
+_default:
+    just --list
+
+# Test out the grammar
+test-grammar:
+    #!/usr/bin/env bash
+    tree-sitter generate
+    tree-sitter test

experiments/tree-sitter-test/package-lock.json

@@ -0,0 +1,380 @@
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+      },
+      "peerDependencies": {
+        "tree-sitter": "^0.21.0"
+      },
+      "peerDependenciesMeta": {
+        "tree_sitter": {
+          "optional": true
+        }
+      }
+    },
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+    "node_modules/util-deprecate": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/util-deprecate/-/util-deprecate-1.0.2.tgz",
+      "integrity": "sha512-EPD5q1uXyFxJpCrLnCc1nHnq3gOa6DZBocAIiI2TaSCA7VCJ1UJDMagCzIkXNsUYfD1daK//LTEQ8xiIbrHtcw==",
+      "dev": true
+    },
+    "node_modules/wrappy": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
+      "integrity": "sha512-l4Sp/DRseor9wL6EvV2+TuQn63dMkPjZ/sp9XkghTEbV9KlPS1xUsZ3u7/IQO4wxtcFB4bgpQPRcR3QCvezPcQ==",
+      "dev": true
+    },
+    "node_modules/yallist": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
+      "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
+      "dev": true
+    }
+  }
+}

experiments/tree-sitter-test/package.json

@@ -0,0 +1,38 @@
+{
+  "name": "tree-sitter-test",
+  "version": "1.0.0",
+  "main": "index.js",
+  "types": "bindings/node",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "install": "node-gyp-build",
+    "prebuildify": "prebuildify --napi --strip"
+  },
+  "author": "",
+  "license": "ISC",
+  "description": "",
+  "dependencies": {
+    "node-addon-api": "^7.1.0",
+    "node-gyp-build": "^4.8.0"
+  },
+  "peerDependencies": {
+    "tree-sitter": "^0.21.0"
+  },
+  "peerDependenciesMeta": {
+    "tree_sitter": {
+      "optional": true
+    }
+  },
+  "devDependencies": {
+    "prebuildify": "^6.0.0",
+    "tree-sitter-cli": "^0.22.5"
+  },
+  "files": [
+    "grammar.js",
+    "binding.gyp",
+    "prebuilds/**",
+    "bindings/node/*",
+    "queries/*",
+    "src/**"
+  ]
+}

experiments/tree-sitter-test/test/corpus/test.txt

@@ -0,0 +1,26 @@
+=============
+Initial test
+=============
+fn main() {
+
+}
+----
+(source_file
+    (function_definition
+        (identifier)
+        (parameter_list)
+        (block)
+    )
+)
+
+====
+Another test
+====
+
+fn yolo() bool { }
+
+----
+
+(source_file
+    (function_definition
+    (identifier) (parameter_list) (primitive_type) (block)))

maaru/Cargo.toml

@@ -1,11 +0,0 @@
-[package]
-name = "maaru-lang"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-
-[dependencies]
-itertools = "0.5.8"
-take_mut = "0.1.3"
-llvm-sys = "*"
-
-schala-repl = { path = "../schala-repl" }

maaru/src/eval.rs

@@ -1,481 +0,0 @@
-extern crate take_mut;
-
-use std::collections::HashMap;
-use std::collections::VecDeque;
-use parser::{AST, Statement, Expression, Function, Callable, BinOp};
-use std::rc::Rc;
-use std::io::{Write, Stdout, BufWriter};
-use std::convert::From;
-
-use parser::Expression::*;
-use parser::Statement::*;
-
-type Reduction<T> = (T, Option<SideEffect>);
-
-#[derive(Debug, Clone)]
-enum ReducedValue {
-    StringLiteral(Rc<String>),
-    ListLiteral(VecDeque<Expression>),
-    StructLiteral(VecDeque<(Rc<String>, Expression)>),
-    Number(f64),
-    Lambda(Function),
-}
-
-impl From<ReducedValue> for Expression {
-    fn from(rv: ReducedValue) -> Expression {
-        match rv {
-            ReducedValue::Number(n) => Expression::Number(n),
-            ReducedValue::StringLiteral(n) => Expression::StringLiteral(n),
-            ReducedValue::Lambda(f) => Expression::Lambda(f),
-            ReducedValue::ListLiteral(items) => Expression::ListLiteral(items),
-            ReducedValue::StructLiteral(items) => Expression::StructLiteral(items),
-        }
-    }
-}
-
-impl From<Expression> for ReducedValue {
-    fn from(rv: Expression) -> ReducedValue {
-        match rv {
-            Expression::Number(n) => ReducedValue::Number(n),
-            Expression::StringLiteral(n) => ReducedValue::StringLiteral(n),
-            Expression::Lambda(f) => ReducedValue::Lambda(f),
-            Expression::ListLiteral(items) => ReducedValue::ListLiteral(items),
-            Expression::StructLiteral(items) => ReducedValue::StructLiteral(items),
-            _ => panic!("trying to store a non-fully-reduced variable"),
-        }
-    }
-}
-
-fn get_indexer(f: f64) -> Option<usize> {
-    if f.fract() == 0.0 {
-        if f.trunc() >= 0.0 {
-            return Some(f.trunc() as usize);
-        }
-    }
-    None
-}
-
-#[derive(Debug)]
-enum SideEffect {
-    Print(String),
-    AddBinding(Rc<String>, ReducedValue),
-}
-
-pub struct Evaluator<'a> {
-    parent: Option<&'a Evaluator<'a>>,
-    variables: HashMap<String, ReducedValue>,
-    stdout: BufWriter<Stdout>,
-    pub trace_evaluation: bool,
-}
-
-impl<'a> Evaluator<'a> {
-    pub fn new(parent: Option<&'a Evaluator>) -> Evaluator<'a> {
-        Evaluator {
-            variables: HashMap::new(),
-            parent: parent,
-            stdout: BufWriter::new(::std::io::stdout()),
-            trace_evaluation: parent.map_or(false, |e| e.trace_evaluation),
-        }
-    }
-
-    pub fn run(&mut self, ast: AST) -> Vec<String> {
-        ast.into_iter()
-            .map(|astnode| format!("{}", self.reduction_loop(astnode)))
-            .collect()
-
-    }
-
-    fn add_binding(&mut self, var: String, value: ReducedValue) {
-        self.variables.insert(var, value);
-    }
-
-    fn lookup_binding(&self, var: &str) -> Option<ReducedValue> {
-        match self.variables.get(var) {
-            Some(expr) => Some(expr.clone()),
-            None => match self.parent {
-                Some(env) => env.lookup_binding(var),
-                None => None
-            }
-        }
-    }
-}
-
-trait Evaluable {
-    fn is_reducible(&self) -> bool;
-}
-
-impl Evaluable for Statement {
-    fn is_reducible(&self) -> bool {
-        match self {
-            &ExprNode(ref expr) => expr.is_reducible(),
-            &FuncDefNode(_) => true,
-        }
-    }
-}
-
-impl Evaluable for Expression {
-    fn is_reducible(&self) -> bool {
-        match *self {
-            Null => false,
-            StringLiteral(_) => false,
-            Lambda(_) => false,
-            Number(_) => false,
-            ListLiteral(ref items) => {
-                items.iter().any(|x| x.is_reducible())
-            }
-            StructLiteral(ref items) => {
-                items.iter().any(|pair| pair.1.is_reducible())
-            }
-            _ => true,
-        }
-    }
-}
-
-impl Expression {
-    fn is_truthy(&self) -> bool {
-        match *self {
-            Null => false,
-            StringLiteral(ref s) if **s == "" => false,
-            Number(n) if n == 0.0 => false,
-            _ => true,
-        }
-    }
-}
-
-fn is_assignment(op: &BinOp) -> bool {
-    use self::BinOp::*;
-    match *op {
-        Assign | AddAssign | SubAssign |
-        MulAssign | DivAssign => true,
-        _ => false,
-    }
-}
-
-impl<'a> Evaluator<'a> {
-    fn reduction_loop(&mut self, mut node: Statement) -> Statement {
-        loop {
-            node = self.step(node);
-            if !node.is_reducible() {
-                break;
-            }
-        }
-        node
-    }
-
-    fn step(&mut self, node: Statement) -> Statement {
-        let mut trace = String::new();
-        if self.trace_evaluation {
-            trace.push_str(&format!("Step: {:?}", node));
-        }
-
-        let (new_node, side_effect) = self.reduce_astnode(node);
-
-        if self.trace_evaluation {
-            trace.push_str(&format!(" ➜ {:?}", new_node));
-        }
-        if let Some(s) = side_effect {
-            if self.trace_evaluation {
-                trace.push_str(&format!(" | side-effect: {:?}", s));
-            }
-            self.perform_side_effect(s);
-        }
-        if self.trace_evaluation {
-            println!("{}", trace);
-        }
-        new_node
-    }
-
-    fn perform_side_effect(&mut self, side_effect: SideEffect) {
-        use self::SideEffect::*;
-        match side_effect {
-            Print(s) => {
-                write!(self.stdout, "{}\n", s).unwrap();
-                match self.stdout.flush() {
-                    Ok(_) => (),
-                    Err(_) => println!("Could not flush stdout"),
-                };
-            }
-            AddBinding(var, value) => {
-                self.add_binding((*var).clone(), value);
-            },
-        }
-    }
-
-    fn reduce_astnode(&mut self, node: Statement) -> Reduction<Statement> {
-        match node {
-            ExprNode(expr) => {
-                if expr.is_reducible() {
-                    let (new_expr, side_effect) = self.reduce_expr(expr);
-                    (ExprNode(new_expr), side_effect)
-                } else {
-                    (ExprNode(expr), None)
-                }
-            }
-            FuncDefNode(func) => {
-                let name = func.prototype.name.clone();
-                let reduced_value = ReducedValue::Lambda(func.clone());
-                let binding = Some(SideEffect::AddBinding(name, reduced_value));
-                (ExprNode(Expression::Lambda(func)), binding)
-            }
-        }
-    }
-
-    //TODO I probably want another Expression variant that holds a ReducedValue
-    fn reduce_expr(&mut self, expression: Expression) -> Reduction<Expression> {
-        match expression {
-            Null => (Null, None),
-            e @ StringLiteral(_) => (e, None),
-            e @ Number(_) => (e, None),
-            e @ Lambda(_) => (e, None),
-            Variable(ref var) => {
-                match self.lookup_binding(var).map(|x| x.into()) {
-                    None => (Null, None),
-                    Some(expr) => (expr, None),
-                }
-            }
-            BinExp(op, mut left, mut right) => {
-                if right.is_reducible() {
-                    let mut side_effect = None;
-                    take_mut::take(right.as_mut(), |expr| { let (a, b) = self.reduce_expr(expr); side_effect = b; a});
-                    return (BinExp(op, left, right), side_effect);
-                }
-
-                if let BinOp::Assign = op {
-                    return match *left {
-                        Variable(var) => {
-                            let reduced_value: ReducedValue = ReducedValue::from(*right);
-                            let binding = SideEffect::AddBinding(var, reduced_value);
-                            (Null, Some(binding))
-                        },
-                        _ => (Null, None)
-                    };
-                }
-
-                if is_assignment(&op) {
-                    use self::BinOp::*;
-                    let new_op = match op {
-                        AddAssign => Add,
-                        SubAssign => Sub,
-                        MulAssign => Mul,
-                        DivAssign => Div,
-                        _ => unreachable!(),
-                    };
-
-                    let reduction =
-                        BinExp(BinOp::Assign,
-                               Box::new(*left.clone()),
-                               Box::new(BinExp(new_op, left, right))
-                              );
-
-                    return (reduction, None);
-                }
-
-                if left.is_reducible() {
-                    let mut side_effect = None;
-                    take_mut::take(left.as_mut(), |expr| { let (a, b) = self.reduce_expr(expr); side_effect = b; a});
-                    (BinExp(op, left, right), side_effect)
-                } else {
-                    (self.reduce_binop(op, *left, *right), None) //can assume both arguments are maximally reduced
-                }
-            }
-            Call(callable, mut args) => {
-                let mut f = true;
-                for arg in args.iter_mut() {
-                    if arg.is_reducible() {
-                        take_mut::take(arg, |arg| self.reduce_expr(arg).0);
-                        f = false;
-                        break;
-                    }
-                }
-                if f {
-                    self.reduce_call(callable, args)
-                } else {
-                    (Call(callable, args), None)
-                }
-            }
-            While(test, body) => {
-                let mut block = VecDeque::from(body.clone());
-                block.push_back(While(test.clone(), body.clone()));
-                let reduction = Conditional(test, Box::new(Block(block)), None); 
-                (reduction, None)
-            }
-            Conditional(box test, then_block, else_block) => {
-                if test.is_reducible() {
-                    let (new_test, new_effect) = self.reduce_expr(test);
-                    (Conditional(Box::new(new_test), then_block, else_block), new_effect)
-                } else {
-                    if test.is_truthy() {
-                        (*then_block, None)
-                    } else {
-                        match else_block {
-                            Some(box expr) => (expr, None),
-                            None => (Null, None),
-                        }
-                    }
-                }
-            }
-            Block(mut exprs) => {
-                let first = exprs.pop_front();
-                match first {
-                    None => (Null, None),
-                    Some(expr) => {
-                        if exprs.len() == 0 {
-                            (expr, None)
-                        } else {
-                            if expr.is_reducible() {
-                                let (new, side_effect) = self.reduce_expr(expr);
-                                exprs.push_front(new);
-                                (Block(exprs), side_effect)
-                            } else {
-                                (Block(exprs), None)
-                            }
-                        }
-                    }
-                }
-            }
-            Index(mut expr, mut index_expr) => {
-                if index_expr.is_reducible() {
-                    let mut side_effect = None;
-                    take_mut::take(index_expr.as_mut(), |expr| { let (a, b) = self.reduce_expr(expr); side_effect = b; a});
-                    return (Index(expr, index_expr), side_effect)
-                }
-
-                if expr.is_reducible() {
-                    let mut side_effect = None;
-                    take_mut::take(expr.as_mut(), |expr| { let (a, b) = self.reduce_expr(expr); side_effect = b; a});
-                    return (Index(expr, index_expr), side_effect);
-                }
-
-                match (*expr, *index_expr) {
-                    (ListLiteral(list_items), Number(n)) => {
-                        let indexed_expr = get_indexer(n).and_then(|i| list_items.get(i));
-                        if let Some(e) = indexed_expr {
-                            (e.clone(), None)
-                        } else {
-                            (Null, None)
-                        }
-                    }
-                    (StructLiteral(items), StringLiteral(s)) => {
-                        for item in items {
-                            if s == item.0 {
-                                return (item.1.clone(), None); //TODO this is hella inefficient
-                            }
-                        }
-                        (Null, None)
-                    },
-                    _ => (Null, None)
-                }
-            }
-            ListLiteral(mut exprs) => {
-                let mut side_effect = None;
-                for expr in exprs.iter_mut() {
-                    if expr.is_reducible() {
-                        take_mut::take(expr, |expr| {
-                            let (a, b) = self.reduce_expr(expr);
-                            side_effect = b;
-                            a
-                        });
-                        break;
-                    }
-                }
-                (ListLiteral(exprs), side_effect)
-            },
-
-            StructLiteral(mut items) => {
-                let mut side_effect = None;
-                for pair in items.iter_mut() {
-                    if pair.1.is_reducible() {
-                        take_mut::take(pair, |pair| {
-                            let (name, expr) = pair;
-                            let (a, b) = self.reduce_expr(expr);
-                            side_effect = b;
-                            (name, a)
-                        });
-                        break;
-                    }
-                }
-
-                (StructLiteral(items), side_effect)
-            }
-        }
-    }
-
-    fn reduce_binop(&mut self, op: BinOp, left: Expression, right: Expression) -> Expression {
-        use self::BinOp::*;
-        let truthy = Number(1.0);
-        let falsy = Null;
-        match (op, left, right) {
-            (Add, Number(l), Number(r)) => Number(l + r),
-            (Add, StringLiteral(s1), StringLiteral(s2)) => StringLiteral(Rc::new(format!("{}{}", *s1, *s2))),
-            (Add, StringLiteral(s1), Number(r)) => StringLiteral(Rc::new(format!("{}{}", *s1, r))),
-            (Add, Number(l), StringLiteral(s1)) => StringLiteral(Rc::new(format!("{}{}", l, *s1))),
-            (Sub, Number(l), Number(r)) => Number(l - r),
-            (Mul, Number(l), Number(r)) => Number(l * r),
-            (Div, Number(l), Number(r)) if r != 0.0 => Number(l / r),
-            (Mod, Number(l), Number(r)) => Number(l % r),
-            (Less, Number(l), Number(r)) => if l < r { truthy } else { falsy },
-            (LessEq, Number(l), Number(r)) => if l <= r { truthy } else { falsy },
-            (Greater, Number(l), Number(r)) => if l > r { truthy } else { falsy },
-            (GreaterEq, Number(l), Number(r)) => if l >= r { truthy } else { falsy },
-            (Equal, Number(l), Number(r)) => if l == r { truthy } else { falsy },
-            (Equal, Null, Null) => truthy,
-            (Equal, StringLiteral(s1), StringLiteral(s2)) => if s1 == s2 { truthy } else { falsy },
-            (Equal, _, _) => falsy,
-            _ => falsy,
-        }
-    }
-
-    fn reduce_call(&mut self, callable: Callable, arguments: Vec<Expression>) -> Reduction<Expression> {
-        if let Some(res) = handle_builtin(&callable, &arguments) {
-            return res;
-        }
-
-        let function = match callable {
-            Callable::Lambda(func) => func.clone(),
-            Callable::NamedFunction(name) => {
-                match self.lookup_binding(&*name) {
-                    Some(ReducedValue::Lambda(func)) => func,
-                    _ => return (Null, None),
-                }
-            }
-        };
-        if function.prototype.parameters.len() != arguments.len() {
-            return (Null, None);
-        }
-
-        let mut evaluator = Evaluator::new(Some(self));
-        for (binding, expr) in function.prototype.parameters.iter().zip(arguments.iter()) {
-            evaluator.add_binding((**binding).clone(), expr.clone().into());
-        }
-
-        let nodes = function.body.iter().map(|node| node.clone());
-        let mut retval = ExprNode(Null);
-        for n in nodes {
-            retval = evaluator.reduction_loop(n);
-        }
-
-        match retval {
-            ExprNode(expr) => (expr, None),
-            FuncDefNode(_) => panic!("This should never happen! A maximally-reduced node\
-            should never be a function definition!")
-        }
-    }
-}
-
-fn handle_builtin(callable: &Callable, arguments: &Vec<Expression>) -> Option<Reduction<Expression>> {
-    let name: &str = match *callable {
-        Callable::NamedFunction(ref name) => *&name,
-        _ => return None,
-    };
-
-    match name {
-        "print" => {
-            let mut s = String::new();
-            for arg in arguments {
-                s.push_str(&format!("{} ", arg));
-            }
-            return Some((Null, Some(SideEffect::Print(s))));
-        },
-        _ => None
-    }
-}

maaru/src/lib.rs

@@ -1,78 +0,0 @@
-#![feature(box_patterns)]
-
-extern crate schala_repl;
-
-mod tokenizer;
-mod parser;
-mod eval;
-
-#[derive(Debug)]
-pub struct TokenError {
-    pub msg: String,
-}
-
-impl TokenError {
-    pub fn new(msg: &str) -> TokenError {
-        TokenError { msg: msg.to_string() }
-    }
-}
-
-pub use self::eval::Evaluator as MaaruEvaluator;
-
-pub struct Maaru<'a> {
-  evaluator: MaaruEvaluator<'a>
-}
-
-impl<'a> Maaru<'a> {
-  pub fn new() -> Maaru<'a> {
-    Maaru {
-      evaluator: MaaruEvaluator::new(None),
-    }
-  }
-}
-
-/*
-fn execute_pipeline(&mut self, input: &str, options: &EvalOptions) -> Result<String, String> {
-  let mut output = UnfinishedComputation::default();
-
-  let tokens = match tokenizer::tokenize(input) {
-    Ok(tokens) => {
-      if let Some(_) = options.debug_passes.get("tokens") {
-        output.add_artifact(TraceArtifact::new("tokens", format!("{:?}", tokens)));
-      }
-      tokens
-    },
-    Err(err) => {
-      return output.finish(Err(format!("Tokenization error: {:?}\n", err.msg)))
-    }
-  };
-
-  let ast = match parser::parse(&tokens, &[]) {
-    Ok(ast) => {
-      if let Some(_) = options.debug_passes.get("ast") {
-        output.add_artifact(TraceArtifact::new("ast", format!("{:?}", ast)));
-      }
-      ast
-    },
-    Err(err) => {
-      return output.finish(Err(format!("Parse error: {:?}\n", err.msg)))
-    }
-  };
-  let mut evaluation_output = String::new();
-  for s in self.evaluator.run(ast).iter() {
-    evaluation_output.push_str(s);
-  }
-  Ok(evaluation_output)
-}
-*/
-
-/*
-impl<'a> ProgrammingLanguageInterface for Maaru<'a> {
-  fn get_language_name(&self) -> String {
-    "Maaru".to_string()
-  }
-  fn get_source_file_suffix(&self) -> String {
-    format!("maaru")
-  }
-}
-  */

maaru/src/parser.rs

@@ -1,755 +0,0 @@
-use tokenizer::{Token, Kw, OpTok};
-use tokenizer::Token::*;
-
-use std::fmt;
-use std::collections::VecDeque;
-use std::rc::Rc;
-use std::convert::From;
-
-// Grammar
-// program := (statement delimiter ?)*
-// delimiter := Newline | Semicolon
-// statement := declaration | expression
-// declaration :=  FN prototype LCurlyBrace (statement)* RCurlyBrace
-// prototype := identifier LParen identlist RParen
-// identlist := Ident (Comma Ident)* | ε
-// exprlist  := Expression (Comma Expression)* | ε
-// itemlist  := Ident COLON Expression (Comma Ident COLON Expression)* | ε
-//
-// expression := postop_expression (op postop_expression)*
-// postop_expression := primary_expression postop
-// primary_expression :=  number_expr | String | identifier_expr | paren_expr | conditional_expr | while_expr | lambda_expr | list_expr | struct_expr
-// number_expr := (PLUS | MINUS ) number_expr | Number
-// identifier_expr := call_expression | Variable
-// list_expr := LSquareBracket exprlist RSquareBracket
-// struct_expr := LCurlyBrace itemlist RCurlyBrace
-// call_expression := Identifier LParen exprlist RParen
-// while_expr := WHILE primary_expression LCurlyBrace (expression delimiter)* RCurlyBrace
-// paren_expr := LParen expression RParen
-// conditional_expr := IF expression LCurlyBrace (expression delimiter)* RCurlyBrace (LCurlyBrace (expresion delimiter)* RCurlyBrace)?
-// lambda_expr := FN LParen identlist RParen LCurlyBrace (expression delimiter)* RCurlyBrace
-// lambda_call :=  | LParen exprlist RParen
-// postop := ε | LParen exprlist RParen | LBracket expression RBracket
-// op := '+', '-', etc.
-//
-
-pub type AST = Vec<Statement>;
-
-#[derive(Debug, Clone)]
-pub enum Statement {
-    ExprNode(Expression),
-    FuncDefNode(Function),
-}
-
-impl fmt::Display for Statement {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        use self::Statement::*;
-        match *self {
-            ExprNode(ref expr) => write!(f, "{}", expr),
-            FuncDefNode(_) => write!(f, "UNIMPLEMENTED"),
-        }
-    }
-}
-
-#[derive(Debug, Clone)]
-pub struct Function {
-    pub prototype: Prototype,
-    pub body: Vec<Statement>,
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct Prototype {
-    pub name: Rc<String>,
-    pub parameters: Vec<Rc<String>>,
-}
-
-#[derive(Debug, Clone)]
-pub enum Expression {
-    Null,
-    StringLiteral(Rc<String>),
-    Number(f64),
-    Variable(Rc<String>),
-    BinExp(BinOp, Box<Expression>, Box<Expression>),
-    Call(Callable, Vec<Expression>),
-    Conditional(Box<Expression>, Box<Expression>, Option<Box<Expression>>),
-    Lambda(Function),
-    Block(VecDeque<Expression>),
-    While(Box<Expression>, Vec<Expression>),
-    Index(Box<Expression>, Box<Expression>),
-    ListLiteral(VecDeque<Expression>),
-    StructLiteral(VecDeque<(Rc<String>, Expression)>),
-}
-
-#[derive(Clone, Debug)]
-pub enum Callable {
-    NamedFunction(Rc<String>),
-    Lambda(Function),
-}
-
-//TODO this ought to be ReducedExpression
-impl fmt::Display for Expression {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        use self::Expression::*;
-        match *self {
-            Null => write!(f, "null"),
-            StringLiteral(ref s) => write!(f, "\"{}\"", s),
-            Number(n) => write!(f, "{}", n),
-            Lambda(Function { prototype: Prototype { ref name, ref parameters, .. }, .. }) => {
-                write!(f, "«function: {}, {} arg(s)»", name, parameters.len())
-            }
-            ListLiteral(ref items) => {
-                write!(f, "[ ")?;
-                let mut iter = items.iter().peekable();
-                while let Some(item) = iter.next() {
-                    write!(f, "{}", item)?;
-                    if let Some(_) = iter.peek() {
-                        write!(f, ", ")?;
-                    }
-                }
-                write!(f, " ]")
-            }
-            StructLiteral(ref items) => {
-                write!(f, "{} ", "{")?;
-                let mut iter = items.iter().peekable();
-                while let Some(pair) = iter.next() {
-                    write!(f, "{}: {}", pair.0, pair.1)?;
-                    if let Some(_) = iter.peek() {
-                        write!(f, ", ")?;
-                    }
-                }
-                write!(f, "{} ", "}")
-            }
-            _ => write!(f, "UNIMPLEMENTED"),
-        }
-    }
-}
-
-#[derive(Debug, Clone)]
-pub enum BinOp {
-    Add,
-    AddAssign,
-    Sub,
-    SubAssign,
-    Mul,
-    MulAssign,
-    Div,
-    DivAssign,
-    Mod,
-    Less,
-    LessEq,
-    Greater,
-    GreaterEq,
-    Equal,
-    Assign,
-    Custom(String),
-}
-
-impl From<OpTok> for BinOp {
-    fn from(token: OpTok) -> BinOp {
-        use self::BinOp::*;
-        match &token.0[..] {
-            "+" => Add,
-            "+=" => AddAssign,
-            "-" => Sub,
-            "-=" => SubAssign,
-            "*" => Mul,
-            "*=" => MulAssign,
-            "/" => Div,
-            "/=" => DivAssign,
-            "%" => Mod,
-            "<" => Less,
-            "<=" => LessEq,
-            ">" => Greater,
-            ">=" => GreaterEq,
-            "==" => Equal,
-            "=" => Assign,
-            op => Custom(op.to_string()),
-        }
-    }
-}
-
-type Precedence = u8;
-
-// TODO make this support incomplete parses
-pub type ParseResult<T> = Result<T, ParseError>;
-
-#[derive(Debug)]
-pub struct ParseError {
-    pub msg: String,
-    pub remaining_tokens: Vec<Token>,
-}
-
-impl ParseError {
-    fn result_from_str<T>(msg: &str) -> ParseResult<T> {
-        Err(ParseError {
-            msg: msg.to_string(),
-            remaining_tokens: vec![],
-        })
-    }
-}
-
-struct Parser {
-    tokens: Vec<Token>,
-}
-
-impl Parser {
-    fn initialize(tokens: &[Token]) -> Parser {
-        let mut tokens = tokens.to_vec();
-        tokens.reverse();
-        Parser { tokens: tokens }
-    }
-
-    fn peek(&self) -> Option<Token> {
-        self.tokens.last().map(|x| x.clone())
-    }
-
-    fn next(&mut self) -> Option<Token> {
-        self.tokens.pop()
-    }
-
-    fn get_precedence(&self, op: &OpTok) -> Precedence {
-        match &op.0[..] {
-            "+" => 10,
-            "-" => 10,
-            "*" => 20,
-            "/" => 20,
-            "%" => 20,
-            "==" => 40,
-            "=" | "+=" | "-=" | "*=" | "/=" => 1,
-            ">" | ">=" | "<" | "<=" => 30,
-            _ => 255,
-        }
-    }
-}
-
-macro_rules! expect {
-    ($self_:expr, $token:pat) => {
-        match $self_.peek() {
-            Some($token) => {$self_.next();},
-            Some(x) => {
-                let err = format!("Expected `{:?}` but got `{:?}`", stringify!($token), x);
-                return ParseError::result_from_str(&err)
-            },
-            None => {
-                let err = format!("Expected `{:?}` but got end of input", stringify!($token));
-                return ParseError::result_from_str(&err) //TODO make this not require 2 stringifications
-            }
-
-        }
-    }
-}
-
-macro_rules! expect_identifier {
-    ($self_:expr) => {
-        match $self_.peek() {
-            Some(Identifier(s)) => {$self_.next(); s},
-            Some(x) => return ParseError::result_from_str(&format!("Expected identifier, but got {:?}", x)),
-            None => return ParseError::result_from_str("Expected identifier, but got end of input"),
-        }
-    }
-}
-
-macro_rules! skip_whitespace {
-    ($_self: expr) => {
-        loop {
-            match $_self.peek() {
-                Some(ref t) if is_delimiter(t) => {
-                    $_self.next();
-                    continue;
-                }
-                _ => break,
-            }
-        }
-    }
-}
-
-macro_rules! delimiter_block {
-    ($_self: expr, $try_parse: ident, $($break_pattern: pat)|+) => {
-        {
-        let mut acc = Vec::new();
-        loop {
-            match $_self.peek() {
-                None => break,
-                Some(ref t) if is_delimiter(t) => { $_self.next(); continue; },
-                $($break_pattern)|+ => break,
-                _ => {
-                    let a = try!($_self.$try_parse());
-                    acc.push(a);
-                }
-            }
-        }
-        acc
-        }
-    }
-}
-
-fn is_delimiter(token: &Token) -> bool {
-    match *token {
-        Newline | Semicolon => true,
-        _ => false,
-    }
-}
-
-impl Parser {
-    fn program(&mut self) -> ParseResult<AST> {
-        let mut ast = Vec::new(); //TODO have this come from previously-parsed tree
-        loop {
-            let result: ParseResult<Statement> = match self.peek() {
-                Some(ref t) if is_delimiter(t) => {
-                    self.next();
-                    continue;
-                }
-                Some(_) => self.statement(),
-                None => break,
-            };
-
-            match result {
-                Ok(node) => ast.push(node),
-                Err(mut err) => {
-                    err.remaining_tokens = self.tokens.clone();
-                    err.remaining_tokens.reverse();
-                    return Err(err);
-                }
-            }
-        }
-        Ok(ast)
-    }
-
-    fn statement(&mut self) -> ParseResult<Statement> {
-        let node: Statement = match self.peek() {
-            Some(Keyword(Kw::Fn)) => self.declaration()?,
-            Some(_) => Statement::ExprNode(self.expression()?),
-            None => panic!("Unexpected end of tokens"),
-        };
-        Ok(node)
-    }
-
-    fn declaration(&mut self) -> ParseResult<Statement> {
-        expect!(self, Keyword(Kw::Fn));
-        let prototype = self.prototype()?;
-        expect!(self, LCurlyBrace);
-        let body = self.body()?;
-        expect!(self, RCurlyBrace);
-        Ok(Statement::FuncDefNode(Function {
-            prototype: prototype,
-            body: body,
-        }))
-    }
-
-    fn prototype(&mut self) -> ParseResult<Prototype> {
-        let name = expect_identifier!(self);
-        expect!(self, LParen);
-        let parameters = self.identlist()?;
-        expect!(self, RParen);
-        Ok(Prototype {
-            name: name,
-            parameters: parameters,
-        })
-    }
-
-    fn identlist(&mut self) -> ParseResult<Vec<Rc<String>>> {
-        let mut args = Vec::new();
-        while let Some(Identifier(name)) = self.peek() {
-            args.push(name.clone());
-            self.next();
-            match self.peek() {
-                Some(Comma) => {self.next();},
-                _ => break,
-            }
-        }
-        Ok(args)
-    }
-
-    fn exprlist(&mut self) -> ParseResult<Vec<Expression>> {
-        let mut exprs = Vec::new();
-        loop {
-            if let Some(RParen) = self.peek() {
-                break;
-            }
-            let exp = self.expression()?;
-            exprs.push(exp);
-            match self.peek() {
-                Some(Comma) => {self.next();},
-                _ => break,
-            }
-        }
-        Ok(exprs)
-    }
-
-    fn itemlist(&mut self) -> ParseResult<VecDeque<(Rc<String>, Expression)>> {
-        let mut items = VecDeque::new();
-        loop {
-            if let Some(RCurlyBrace) = self.peek() {
-                break;
-            }
-            let name = expect_identifier!(self);
-            expect!(self, Colon);
-            let expr = self.expression()?;
-            items.push_back((name, expr));
-            match self.peek() {
-                Some(Comma) => {self.next();},
-                _ => break,
-            };
-        }
-        Ok(items)
-    }
-
-    fn body(&mut self) -> ParseResult<Vec<Statement>> {
-        let statements = delimiter_block!(
-            self,
-            statement,
-            Some(RCurlyBrace)
-        );
-        Ok(statements)
-    }
-
-    fn expression(&mut self) -> ParseResult<Expression> {
-        let lhs: Expression = self.postop_expression()?;
-        self.precedence_expr(lhs, 0)
-    }
-
-    fn precedence_expr(&mut self,
-                       mut lhs: Expression,
-                       min_precedence: u8)
-                       -> ParseResult<Expression> {
-        while let Some(Operator(op)) = self.peek() {
-            let precedence = self.get_precedence(&op);
-            if precedence < min_precedence {
-                break;
-            }
-            self.next();
-            let mut rhs = self.postop_expression()?;
-            while let Some(Operator(ref op)) = self.peek() {
-                if self.get_precedence(op) > precedence {
-                    let new_prec = self.get_precedence(op);
-                    rhs = self.precedence_expr(rhs, new_prec)?;
-
-                } else {
-                    break;
-                }
-            }
-
-            lhs = Expression::BinExp(op.into(), Box::new(lhs), Box::new(rhs));
-        }
-        Ok(lhs)
-    }
-
-    fn postop_expression(&mut self) -> ParseResult<Expression> {
-        use self::Expression::*;
-        let expr = self.primary_expression()?;
-        let ret = match self.peek() {
-            Some(LParen) => {
-                let args = self.call_expression()?;
-                match expr {
-                    Lambda(f) => Call(Callable::Lambda(f), args),
-                    e => {
-                        let err = format!("Expected lambda expression before a call, got {:?}", e);
-                        return ParseError::result_from_str(&err);
-                    },
-                }
-            },
-            Some(LSquareBracket) => {
-                expect!(self, LSquareBracket);
-                let index_expr = self.expression()?;
-                expect!(self, RSquareBracket);
-                Index(Box::new(expr), Box::new(index_expr))
-            },
-            _ => {
-                expr
-            }
-        };
-        Ok(ret)
-    }
-
-    fn primary_expression(&mut self) -> ParseResult<Expression> {
-        Ok(match self.peek() {
-            Some(Keyword(Kw::Null)) => {
-                self.next();
-                Expression::Null
-            }
-            Some(NumLiteral(_)) => self.number_expression()?,
-            Some(Operator(OpTok(ref a))) if **a == "+" || **a == "-" => self.number_expression()?,
-            Some(StrLiteral(s)) => {
-                self.next();
-                Expression::StringLiteral(s)
-            }
-            Some(Keyword(Kw::If)) => self.conditional_expr()?,
-            Some(Keyword(Kw::While)) => self.while_expr()?,
-            Some(Identifier(_)) => self.identifier_expr()?,
-            Some(Token::LParen) => self.paren_expr()?,
-            Some(Keyword(Kw::Fn)) => self.lambda_expr()?,
-            Some(Token::LSquareBracket) => self.list_expr()?,
-            Some(Token::LCurlyBrace) => self.struct_expr()?,
-            Some(e) => {
-                return ParseError::result_from_str(&format!("Expected primary expression, got \
-                                                             {:?}",
-                                                            e));
-            }
-            None => return ParseError::result_from_str("Expected primary expression received EoI"),
-        })
-    }
-
-    fn list_expr(&mut self) -> ParseResult<Expression> {
-        expect!(self, LSquareBracket);
-        let exprlist: Vec<Expression> = self.exprlist()?;
-        expect!(self, RSquareBracket);
-
-        Ok(Expression::ListLiteral(VecDeque::from(exprlist)))
-    }
-
-    fn struct_expr(&mut self) -> ParseResult<Expression> {
-        expect!(self, LCurlyBrace);
-        let struct_items = self.itemlist()?;
-        expect!(self, RCurlyBrace);
-        Ok(Expression::StructLiteral(struct_items))
-    }
-
-    fn number_expression(&mut self) -> ParseResult<Expression> {
-        let mut multiplier = 1;
-        loop {
-            match self.peek() {
-                Some(NumLiteral(n)) => {
-                    self.next();
-                    return Ok(Expression::Number(n * multiplier as f64));
-                }
-                Some(Operator(OpTok(ref a))) if **a == "+" => {
-                    self.next();
-                }
-                Some(Operator(OpTok(ref a))) if **a == "-" => {
-                    multiplier *= -1;
-                    self.next();
-                }
-                Some(e) => {
-                    return ParseError::result_from_str(
-                            &format!("Expected +, - or number, got {:?}", e));
-                }
-                None => {
-                    return ParseError::result_from_str(
-                            &format!("Expected +, - or number, got EoI"));
-                }
-            }
-        }
-    }
-
-    fn lambda_expr(&mut self) -> ParseResult<Expression> {
-        use self::Expression::*;
-        expect!(self, Keyword(Kw::Fn));
-        skip_whitespace!(self);
-        expect!(self, LParen);
-        let parameters = self.identlist()?;
-        expect!(self, RParen);
-        skip_whitespace!(self);
-        expect!(self, LCurlyBrace);
-        let body = self.body()?;
-        expect!(self, RCurlyBrace);
-
-        let prototype = Prototype {
-            name: Rc::new("a lambda yo!".to_string()),
-            parameters: parameters,
-        };
-
-        let function = Function {
-            prototype: prototype,
-            body: body,
-        };
-
-        Ok(Lambda(function))
-    }
-
-    fn while_expr(&mut self) -> ParseResult<Expression> {
-        use self::Expression::*;
-        expect!(self, Keyword(Kw::While));
-        let test = self.expression()?;
-        expect!(self, LCurlyBrace);
-        let body = delimiter_block!(
-            self,
-            expression,
-            Some(RCurlyBrace)
-        );
-        expect!(self, RCurlyBrace);
-        Ok(While(Box::new(test), body))
-    }
-
-    fn conditional_expr(&mut self) -> ParseResult<Expression> {
-        use self::Expression::*;
-        expect!(self, Keyword(Kw::If));
-        let test = self.expression()?;
-        skip_whitespace!(self);
-        expect!(self, LCurlyBrace);
-        skip_whitespace!(self);
-        let then_block = delimiter_block!(
-            self,
-            expression,
-            Some(RCurlyBrace)
-        );
-        expect!(self, RCurlyBrace);
-        skip_whitespace!(self);
-        let else_block = if let Some(Keyword(Kw::Else)) = self.peek() {
-            self.next();
-            skip_whitespace!(self);
-            expect!(self, LCurlyBrace);
-            let else_exprs  = delimiter_block!(
-                self,
-                expression,
-                Some(RCurlyBrace)
-            );
-            Some(else_exprs)
-        } else {
-            None
-        };
-        expect!(self, RCurlyBrace);
-        Ok(Conditional(Box::new(test),
-                       Box::new(Block(VecDeque::from(then_block))),
-                       else_block.map(|list| Box::new(Block(VecDeque::from(list))))))
-    }
-
-    fn identifier_expr(&mut self) -> ParseResult<Expression> {
-        let name = expect_identifier!(self);
-        let expr = match self.peek() {
-            Some(LParen) => {
-                let args = self.call_expression()?;
-                Expression::Call(Callable::NamedFunction(name), args)
-            }
-            __ => Expression::Variable(name),
-        };
-        Ok(expr)
-    }
-
-    fn call_expression(&mut self) -> ParseResult<Vec<Expression>> {
-        expect!(self, LParen);
-        let args: Vec<Expression> = self.exprlist()?;
-        expect!(self, RParen);
-        Ok(args)
-    }
-
-    fn paren_expr(&mut self) -> ParseResult<Expression> {
-        expect!(self, Token::LParen);
-        let expr = self.expression()?;
-        expect!(self, Token::RParen);
-        Ok(expr)
-    }
-}
-
-pub fn parse(tokens: &[Token], _parsed_tree: &[Statement]) -> ParseResult<AST> {
-    let mut parser = Parser::initialize(tokens);
-    parser.program()
-}
-
-/*
-#[cfg(test)]
-mod tests {
-    use schala_lang::tokenizer;
-    use super::*;
-    use super::Statement::*;
-    use super::Expression::*;
-
-    macro_rules! parsetest {
-        ($input:expr, $output:pat, $ifexpr:expr) => {
-            {
-            let tokens = tokenizer::tokenize($input).unwrap();
-            let ast = parse(&tokens, &[]).unwrap();
-            match &ast[..] {
-                $output if $ifexpr => (),
-                x => panic!("Error in parse test, got {:?} instead", x)
-            }
-            }
-        }
-    }
-
-    #[test]
-    fn function_parse_test() {
-        use super::Function;
-        parsetest!(
-        "fn a() { 1 + 2 }",
-        &[FuncDefNode(Function {prototype: Prototype { ref name, ref parameters }, ref body})],
-        match &body[..] { &[ExprNode(BinExp(_, box Number(1.0), box Number(2.0)))] => true, _ => false }
-            && **name == "a" && match &parameters[..] { &[] => true, _ => false }
-        );
-
-        parsetest!(
-        "fn a(x,y){ 1 + 2 }",
-        &[FuncDefNode(Function {prototype: Prototype { ref name, ref parameters }, ref body})],
-        match &body[..] { &[ExprNode(BinExp(_, box Number(1.0), box Number(2.0)))] => true, _ => false }
-            && **name == "a" && *parameters[0] == "x" && *parameters[1] == "y" && parameters.len() == 2
-        );
-
-        let t3 = "fn (x) { x + 2 }";
-        let tokens3 = tokenizer::tokenize(t3).unwrap();
-        assert!(parse(&tokens3, &[]).is_err());
-    }
-
-    #[test]
-    fn expression_parse_test() {
-        parsetest!("a", &[ExprNode(Variable(ref s))], **s == "a");
-        parsetest!("a + b",
-            &[ExprNode(BinExp(BinOp::Add, box Variable(ref a), box Variable(ref b)))],
-            **a == "a" && **b == "b");
-        parsetest!("a + b * c",
-            &[ExprNode(BinExp(BinOp::Add, box Variable(ref a), box BinExp(BinOp::Mul, box Variable(ref b), box Variable(ref c))))],
-            **a == "a" && **b == "b" && **c == "c");
-        parsetest!("a * b + c",
-            &[ExprNode(BinExp(BinOp::Add, box BinExp(BinOp::Mul, box Variable(ref a), box Variable(ref b)), box Variable(ref c)))],
-            **a == "a" && **b == "b" && **c == "c");
-        parsetest!("(a + b) * c",
-            &[ExprNode(BinExp(BinOp::Mul, box BinExp(BinOp::Add, box Variable(ref a), box Variable(ref b)), box Variable(ref c)))],
-            **a == "a" && **b == "b" && **c == "c");
-    }
-
-    #[test]
-    fn lambda_parse_test() {
-        use schala_lang::tokenizer;
-        let t1 = "(fn(x) { x + 2 })";
-        let tokens1 = tokenizer::tokenize(t1).unwrap();
-        match parse(&tokens1, &[]).unwrap()[..] {
-            _ => (),
-        }
-
-        let t2 = "fn(x) { x + 2 }";
-        let tokens2 = tokenizer::tokenize(t2).unwrap();
-        assert!(parse(&tokens2, &[]).is_err());
-
-        let t3 = "(fn(x) { x + 10 })(20)";
-        let tokens3 = tokenizer::tokenize(t3).unwrap();
-        match parse(&tokens3, &[]).unwrap() {
-            _ => (),
-        };
-    }
-
-    #[test]
-    fn conditional_parse_test() {
-        use schala_lang::tokenizer;
-        let t1 = "if null { 20 } else { 40 }";
-        let tokens = tokenizer::tokenize(t1).unwrap();
-        match parse(&tokens, &[]).unwrap()[..] {
-            [ExprNode(Conditional(box Null, box Block(_), Some(box Block(_))))] => (),
-            _ => panic!(),
-        }
-
-        let t2 = r"
-        if null {
-            20
-        } else {
-            40
-        }
-        ";
-        let tokens2 = tokenizer::tokenize(t2).unwrap();
-        match parse(&tokens2, &[]).unwrap()[..] {
-            [ExprNode(Conditional(box Null, box Block(_), Some(box Block(_))))] => (),
-            _ => panic!(),
-        }
-
-        let t2 = r"
-        if null {
-            20 } else
-        {
-            40
-        }
-        ";
-        let tokens3 = tokenizer::tokenize(t2).unwrap();
-        match parse(&tokens3, &[]).unwrap()[..] {
-            [ExprNode(Conditional(box Null, box Block(_), Some(box Block(_))))] => (),
-            _ => panic!(),
-        }
-    }
-}
-*/

maaru/src/tokenizer.rs

@@ -1,208 +0,0 @@
-extern crate itertools;
-
-use std::iter::Peekable;
-use std::str::Chars;
-use self::itertools::Itertools;
-use std::rc::Rc;
-
-use TokenError;
-
-#[derive(Debug, Clone, PartialEq)]
-pub enum Token {
-    Newline,
-    Semicolon,
-    LParen,
-    RParen,
-    LSquareBracket,
-    RSquareBracket,
-    LCurlyBrace,
-    RCurlyBrace,
-    Comma,
-    Period,
-    Colon,
-    NumLiteral(f64),
-    StrLiteral(Rc<String>),
-    Identifier(Rc<String>),
-    Operator(OpTok),
-    Keyword(Kw),
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct OpTok(pub Rc<String>);
-
-#[derive(Debug, Clone, PartialEq)]
-pub enum Kw {
-    If,
-    Else,
-    While,
-    Let,
-    Fn,
-    Null,
-}
-
-pub type TokenizeResult = Result<Vec<Token>, TokenError>;
-
-fn is_digit(c: &char) -> bool {
-    c.is_digit(10)
-}
-
-pub fn tokenize(input: &str) -> TokenizeResult {
-    use self::Token::*;
-    let mut tokens = Vec::new();
-    let mut iter: Peekable<Chars> = input.chars().peekable();
-    while let Some(c) = iter.next() {
-        if c == '#' {
-            while let Some(c) = iter.next() {
-                if c == '\n' {
-                    break;
-                }
-            }
-            continue;
-        }
-        let cur_tok = match c {
-            c if char::is_whitespace(c) && c != '\n' => continue,
-            '\n' => Newline,
-            ';' => Semicolon,
-            '(' => LParen,
-            ')' => RParen,
-            ':' => Colon,
-            ',' => Comma,
-            '{' => LCurlyBrace,
-            '}' => RCurlyBrace,
-            '[' => LSquareBracket,
-            ']' => RSquareBracket,
-            '"' => tokenize_str(&mut iter)?,
-            c if !char::is_alphanumeric(c) => tokenize_operator(c, &mut iter)?,
-            c @ '.' | c if is_digit(&c) => tokenize_number_or_period(c, &mut iter)?,
-            c => tokenize_identifier(c, &mut iter)?,
-        };
-        tokens.push(cur_tok);
-    }
-    Ok(tokens)
-}
-
-fn tokenize_str(iter: &mut Peekable<Chars>) -> Result<Token, TokenError> {
-    let mut buffer = String::new();
-    loop {
-        // TODO handle string escapes, interpolation
-        match iter.next() {
-            Some(x) if x == '"' => break,
-            Some(x) => buffer.push(x),
-            None => return Err(TokenError::new("Unclosed quote")),
-        }
-    }
-    Ok(Token::StrLiteral(Rc::new(buffer)))
-}
-
-fn tokenize_operator(c: char, iter: &mut Peekable<Chars>) -> Result<Token, TokenError> {
-    let mut buffer = String::new();
-    buffer.push(c);
-    buffer.extend(iter.peeking_take_while(|x| !char::is_alphanumeric(*x) && !char::is_whitespace(*x))); 
-    Ok(Token::Operator(OpTok(Rc::new(buffer))))
-}
-
-fn tokenize_number_or_period(c: char, iter: &mut Peekable<Chars>) -> Result<Token, TokenError> {
-    if c == '.' && !iter.peek().map_or(false, is_digit) {
-        return Ok(Token::Period);
-    }
-
-    let mut buffer = String::new();
-    buffer.push(c);
-    buffer.extend(iter.peeking_take_while(|x| is_digit(x) || *x == '.'));
-
-    match buffer.parse::<f64>() {
-        Ok(f) => Ok(Token::NumLiteral(f)),
-        Err(_) => Err(TokenError::new("Failed to parse digit")),
-    }
-}
-
-fn tokenize_identifier(c: char, iter: &mut Peekable<Chars>) -> Result<Token, TokenError> {
-    fn ends_identifier(c: &char) -> bool {
-        let c = *c;
-        char::is_whitespace(c) || is_digit(&c) || c == ';' || c == '(' || c == ')' ||
-        c == ',' || c == '.' || c == ',' || c == ':' || c == '[' || c == ']'
-    }
-
-    use self::Token::*;
-    let mut buffer = String::new();
-    buffer.push(c);
-    buffer.extend(iter.peeking_take_while(|x| !ends_identifier(x)));
-
-    Ok(match &buffer[..] {
-        "if" => Keyword(Kw::If),
-        "else" => Keyword(Kw::Else),
-        "while" => Keyword(Kw::While),
-        "let" => Keyword(Kw::Let),
-        "fn" => Keyword(Kw::Fn),
-        "null" => Keyword(Kw::Null),
-        b => Identifier(Rc::new(b.to_string())),
-    })
-}
-
-/*
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use super::Token::*;
-
-    macro_rules! token_test {
-        ($input: expr, $output: pat, $ifexpr: expr) => {
-            let tokens = tokenize($input).unwrap();
-            match tokens[..] {
-                $output if $ifexpr => (),
-                _ => panic!("Actual output: {:?}", tokens),
-            }
-        }
-    }
-
-    #[test]
-    fn basic_tokeniziation_tests() {
-        token_test!("let a = 3\n",
-                    [Keyword(Kw::Let), Identifier(ref a), Operator(OpTok(ref b)), NumLiteral(3.0), Newline],
-                    **a == "a" && **b == "=");
-
-        token_test!("2+1",
-                    [NumLiteral(2.0), Operator(OpTok(ref a)), NumLiteral(1.0)],
-                    **a == "+");
-
-        token_test!("2 + 1",
-                    [NumLiteral(2.0), Operator(OpTok(ref a)), NumLiteral(1.0)],
-                    **a == "+");
-
-        token_test!("2.3*49.2",
-                   [NumLiteral(2.3), Operator(OpTok(ref a)), NumLiteral(49.2)],
-                   **a == "*");
-
-        token_test!("a+3",
-                    [Identifier(ref a), NumLiteral(3.0)],
-                    **a == "a+");
-
-        assert!(tokenize("2.4.5").is_err());
-
-        token_test!("fn my_func(a) { a ? 3[1] }",
-                    [Keyword(Kw::Fn), Identifier(ref a), LParen, Identifier(ref b), RParen, LCurlyBrace, Identifier(ref c),
-                     Operator(OpTok(ref d)), NumLiteral(3.0), LSquareBracket, NumLiteral(1.0), RSquareBracket, RCurlyBrace],
-                     **a == "my_func" && **b == "a" && **c == "a" && **d == "?");
-    }
-
-    #[test]
-    fn string_test() {
-        token_test!("null + \"a string\"",
-                    [Keyword(Kw::Null), Operator(OpTok(ref a)), StrLiteral(ref b)],
-                    **a == "+" && **b == "a string");
-
-        token_test!("\"{?'q@?\"",
-                    [StrLiteral(ref a)],
-                    **a == "{?'q@?");
-    }
-
-    #[test]
-    fn operator_test() {
-        token_test!("a *> b",
-                   [Identifier(ref a), Operator(OpTok(ref b)), Identifier(ref c)],
-                   **a == "a" && **b == "*>" && **c == "b");
-
-
-    }
-}
-*/

partis/src/lib.rs

@@ -1,17 +0,0 @@
-struct ParseError { }
-
-enum ParseResult<'a, T> {
-  Success(T, &'a str),
-  Failure(ParseError),
-  Incomplete,
-}
-
-
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn it_works() {
-        assert_eq!(2 + 2, 4);
-    }
-
-}

robo/Cargo.toml

@@ -1,11 +0,0 @@
-[package]
-name = "robo-lang"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-
-[dependencies]
-itertools = "0.5.8"
-take_mut = "0.1.3"
-llvm-sys = "*"
-
-schala-repl = { path = "../schala-repl" }

robo/src/lib.rs

@@ -1,158 +0,0 @@
-#![feature(box_patterns)]
-
-extern crate itertools;
-extern crate schala_repl;
-
-use itertools::Itertools;
-use schala_repl::{ProgrammingLanguageInterface, EvalOptions}; 
-
-pub struct Robo {
-}
-
-impl Robo {
-  pub fn new() -> Robo {
-    Robo { }
-  }
-}
-
-#[derive(Debug)]
-pub struct TokenError {
-    pub msg: String,
-}
-
-impl TokenError {
-    pub fn new(msg: &str) -> TokenError {
-        TokenError { msg: msg.to_string() }
-    }
-}
-
-#[allow(dead_code)]
-#[derive(Debug)]
-pub enum Token {
-    StrLiteral(String),
-    Backtick,
-    Newline,
-    LParen,
-    RParen,
-    LBracket,
-    RBracket,
-    LBrace,
-    RBrace,
-    Period,
-    Comma,
-    Colon,
-    Semicolon,
-    SingleQuote,
-    Identifier(String),
-    Operator(String),
-    NumLiteral(Number),
-}
-
-#[allow(dead_code)]
-#[derive(Debug)]
-pub enum Number {
-    IntegerRep(String),
-    FloatRep(String)
-}
-
-#[allow(dead_code)]
-pub type AST = Vec<ASTNode>;
-
-#[allow(dead_code)]
-#[derive(Debug)]
-pub enum ASTNode {
-    FunctionDefinition(String, Expression),
-    ImportStatement(String),
-}
-
-#[allow(dead_code)]
-#[derive(Debug)]
-pub enum Expression {
-
-}
-
-fn tokenize(input: &str) -> Result<Vec<Token>, TokenError> {
-  use self::Token::*;
-  let mut tokens = Vec::new();
-  let mut iter = input.chars().peekable();
-  while let Some(c) = iter.next() {
-    if c == ';' {
-      while let Some(c) = iter.next() {
-        if c == '\n' {
-          break;
-        }
-      }
-      continue;
-    }
-    let cur_tok = match c {
-      c if char::is_whitespace(c) && c != '\n' => continue,
-      '\n' => Newline,
-      '(' => LParen,
-      ')' => RParen,
-      '[' => LBracket,
-      ']' => RBracket,
-      '{' => LBrace,
-      '}' => RBrace,
-      ',' => Comma,
-      ':' => Colon,
-      ';' => Semicolon,
-      '.' => Period,
-      '`' => Backtick,
-      '\'' => SingleQuote,
-      '"' => {
-        let mut buffer = String::new();
-        loop {
-          match iter.next() {
-            Some(x) if x == '"' => break,
-            Some(x) => buffer.push(x),
-            None => return Err(TokenError::new("Unclosed quote")),
-          }
-        }
-        StrLiteral(buffer)
-      }
-      c if c.is_digit(10) => {
-        let mut integer = true;
-        let mut buffer = String::new();
-        buffer.push(c);
-        buffer.extend(iter.peeking_take_while(|x| x.is_digit(10)));
-        if let Some(&'.') = iter.peek() {
-          buffer.push(iter.next().unwrap());
-          integer = false;
-        }
-        buffer.extend(iter.peeking_take_while(|x| x.is_digit(10)));
-        let inner = if integer {
-          Number::IntegerRep(buffer)
-        } else {
-          Number::FloatRep(buffer)
-        };
-        NumLiteral(inner)
-      },
-      c if char::is_alphanumeric(c) => {
-        let mut buffer = String::new();
-        buffer.push(c);
-        buffer.extend(iter.peeking_take_while(|x| char::is_alphanumeric(*x)));
-        Identifier(buffer)
-      },
-      c => {
-        let mut buffer = String::new();
-        buffer.push(c);
-        buffer.extend(iter.peeking_take_while(|x| !char::is_whitespace(*x)));
-        Operator(buffer)
-      }
-    };
-    tokens.push(cur_tok);
-  }
-
-  Ok(tokens)
-}
-
-impl ProgrammingLanguageInterface for Robo {
-  fn get_language_name(&self) -> String {
-    "Robo".to_string()
-  }
-
-  fn get_source_file_suffix(&self) -> String {
-    format!("robo")
-  }
-}
-

rukka/Cargo.toml

@@ -1,11 +0,0 @@
-[package]
-name = "rukka-lang"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-
-[dependencies]
-itertools = "0.5.8"
-take_mut = "0.1.3"
-llvm-sys = "*"
-
-schala-repl = { path = "../schala-repl" }

rukka/src/lib.rs

@@ -1,417 +0,0 @@
-#![feature(box_patterns)]
-
-extern crate itertools;
-extern crate schala_repl;
-
-use itertools::Itertools;
-use schala_repl::{ProgrammingLanguageInterface, EvalOptions};
-use std::iter::Peekable;
-use std::vec::IntoIter;
-use std::str::Chars;
-use std::collections::HashMap;
-
-pub struct EvaluatorState {
-  binding_stack: Vec<HashMap<String, Sexp>>
-}
-
-impl EvaluatorState {
-  fn new() -> EvaluatorState {
-    use self::Sexp::Primitive;
-    use self::PrimitiveFn::*;
-    let mut default_map = HashMap::new();
-    default_map.insert(format!("+"), Primitive(Plus));
-    default_map.insert(format!("-"), Primitive(Minus));
-    default_map.insert(format!("*"), Primitive(Mult));
-    default_map.insert(format!("/"), Primitive(Div));
-    default_map.insert(format!("%"), Primitive(Mod));
-    default_map.insert(format!(">"), Primitive(Greater));
-    default_map.insert(format!("<"), Primitive(Less));
-    default_map.insert(format!("<="), Primitive(LessThanOrEqual));
-    default_map.insert(format!(">="), Primitive(GreaterThanOrEqual));
-    default_map.insert(format!("display"), Primitive(Display));
-
-    EvaluatorState {
-      binding_stack: vec![default_map],
-    }
-  }
-  fn set_var(&mut self, var: String, value: Sexp) {
-    let binding = self.binding_stack.last_mut().unwrap();
-    binding.insert(var, value);
-  }
-  fn get_var(&self, var: &str) -> Option<&Sexp> {
-    for bindings in self.binding_stack.iter().rev() {
-      match bindings.get(var) {
-        Some(x)  => return Some(x),
-        None => (),
-      }
-    }
-    None
-  }
-
-  fn push_env(&mut self) {
-    self.binding_stack.push(HashMap::new());
-  }
-  fn pop_env(&mut self) {
-    self.binding_stack.pop();
-  }
-}
-
-pub struct Rukka {
-  state: EvaluatorState
-}
-
-impl Rukka {
-  pub fn new() -> Rukka { Rukka { state: EvaluatorState::new() } }
-}
-
-impl ProgrammingLanguageInterface for Rukka {
-  fn get_language_name(&self) -> String {
-    "Rukka".to_string()
-  }
-
-  fn get_source_file_suffix(&self) -> String {
-    format!("rukka")
-  }
-}
-
-impl EvaluatorState {
-  fn eval(&mut self, expr: Sexp) -> Result<Sexp, String> {
-    use self::Sexp::*;
-    Ok(match expr {
-      SymbolAtom(ref sym) => match self.get_var(sym) {
-        Some(ref sexp) => {
-          let q: &Sexp = sexp; //WTF? if I delete this line, the copy doesn't work??
-          q.clone() //TODO make this not involve a clone
-        },
-        None => return Err(format!("Variable {} not bound", sym)),
-      },
-      expr @ Primitive(_) => expr,
-      expr @ FnLiteral { .. } => expr,
-      expr @ StringAtom(_) => expr,
-      expr @ NumberAtom(_) => expr,
-      expr @ BoolAtom(_) => expr,
-      Cons(box operator, box operands) => match operator {
-        SymbolAtom(ref sym) if match &sym[..] {
-          "quote" | "eq?" | "cons" | "car" | "cdr" | "atom?" | "define" | "lambda" | "if" | "cond" => true, _ => false
-          } => self.eval_special_form(sym, operands)?,
-        _ => {
-          let evaled = self.eval(operator)?;
-          self.apply(evaled, operands)?
-        }
-      },
-      Nil => Nil,
-    })
-  }
-  fn eval_special_form(&mut self, form: &str, operands: Sexp) -> Result<Sexp, String> {
-    use self::Sexp::*;
-    Ok(match form {
-      "quote" => match operands {
-        Cons(box quoted, box Nil) => quoted,
-        _ => return Err(format!("Bad syntax in quote")),
-      },
-      "eq?" => match operands {//TODO make correct
-        Cons(box lhs, box Cons(box rhs, _)) => BoolAtom(lhs == rhs),
-        _ => BoolAtom(true),
-      },
-      "cons" => match operands {
-        Cons(box cadr, box Cons(box caddr, box Nil)) => {
-          let newl = self.eval(cadr)?;
-          let newr = self.eval(caddr)?;
-          Cons(Box::new(newl), Box::new(newr))
-        },
-        _ => return Err(format!("Bad arguments for cons")),
-      },
-      "car" => match operands {
-        Cons(box car, _) => car,
-        _ => return Err(format!("called car with a non-pair argument")),
-      },
-      "cdr" => match operands {
-        Cons(_, box cdr) => cdr,
-        _ => return Err(format!("called cdr with a non-pair argument")),
-      },
-      "atom?" => match operands {
-        Cons(_, _) => BoolAtom(false),
-        _ => BoolAtom(true),
-      },
-      "define" => match operands {
-        Cons(box SymbolAtom(sym), box Cons(box expr, box Nil)) => {
-          let evaluated = self.eval(expr)?;
-          self.set_var(sym, evaluated);
-          Nil
-        },
-        _ => return Err(format!("Bad assignment")),
-      }
-      "lambda" => match operands {
-        Cons(box mut paramlist, box Cons(box formalexp, box Nil)) => {
-          let mut formal_params = vec![];
-          {
-            let mut ptr = &paramlist;
-            loop {
-              match ptr {
-                &Cons(ref arg, ref rest) => {
-                  if let SymbolAtom(ref sym) = **arg {
-                    formal_params.push(sym.clone());
-                    ptr = rest;
-                  } else {
-                    return Err(format!("Bad lambda format"));
-                  }
-                },
-                _ => break,
-              }
-            }
-          }
-          FnLiteral {
-            formal_params,
-            body: Box::new(formalexp)
-          }
-        },
-        _ => return Err(format!("Bad lambda expression")),
-      },
-      "if" => match operands {
-        Cons(box test, box body) => {
-          let truth_value = test.truthy();
-          match (truth_value, body) {
-            (true, Cons(box consequent, _)) => consequent,
-            (false, Cons(_, box Cons(box alternative, _))) => alternative,
-            _ => return Err(format!("Bad if expression"))
-          }
-        },
-        _ => return Err(format!("Bad if expression"))
-      },
-      s => return Err(format!("Non-existent special form {}; this should never happen", s)),
-    })
-  }
-
-  fn apply(&mut self, function: Sexp, operands: Sexp) -> Result<Sexp, String> {
-    use self::Sexp::*;
-    match function {
-      FnLiteral { formal_params, body } => {
-        self.push_env();
-
-        let mut cur = operands;
-        for param in formal_params {
-          match cur {
-            Cons(box arg, box rest) => {
-              cur = rest;
-              self.set_var(param, arg);
-            },
-            _ => return Err(format!("Bad argument for function application")),
-          }
-        }
-        let result = self.eval(*body);
-        self.pop_env();
-        result
-      },
-      Primitive(prim) => {
-        let mut evaled_operands = Vec::new();
-        let mut cur_operand = operands;
-        loop {
-          match cur_operand {
-            Nil => break,
-            Cons(box l, box rest) => {
-              evaled_operands.push(self.eval(l)?);
-              cur_operand = rest;
-            },
-            _ => return Err(format!("Bad operands list"))
-          }
-        }
-
-        prim.apply(evaled_operands)
-      }
-      _ => return Err(format!("Bad type to apply")),
-    }
-  }
-}
-
-fn read(input: &str) -> Result<Vec<Sexp>, String> {
-  let mut chars: Peekable<Chars> = input.chars().peekable();
-  let mut tokens = tokenize(&mut chars).into_iter().peekable();
-  let mut sexps = Vec::new();
-  while let Some(_) = tokens.peek() {
-    sexps.push(parse(&mut tokens)?);
-  }
-  Ok(sexps)
-}
-
-#[derive(Debug)]
-enum Token {
-  LParen,
-  RParen,
-  Quote,
-  Word(String),
-  StringLiteral(String),
-  NumLiteral(u64),
-}
-
-//TODO make this notion of Eq more sophisticated
-#[derive(Debug, PartialEq, Clone)]
-enum Sexp {
-  SymbolAtom(String),
-  StringAtom(String),
-  NumberAtom(u64),
-  BoolAtom(bool),
-  Cons(Box<Sexp>, Box<Sexp>),
-  Nil,
-  FnLiteral {
-    formal_params: Vec<String>,
-    body: Box<Sexp>
-  },
-  Primitive(PrimitiveFn)
-}
-
-#[derive(Debug, PartialEq, Clone)]
-enum PrimitiveFn {
-  Plus, Minus, Mult, Div, Mod, Greater, Less, GreaterThanOrEqual, LessThanOrEqual, Display
-}
-
-impl PrimitiveFn {
-  fn apply(&self, evaled_operands: Vec<Sexp>) -> Result<Sexp, String> {
-    use self::Sexp::*;
-    use self::PrimitiveFn::*;
-    let op = self.clone();
-    Ok(match op {
-      Display => {
-        for arg in evaled_operands {
-          print!("{}\n", arg.print());
-        }
-        Nil
-      },
-      Plus | Mult => {
-        let mut result = match op { Plus => 0, Mult => 1, _ => unreachable!() };
-        for arg in evaled_operands {
-          if let NumberAtom(n) = arg {
-            if let Plus = op {
-              result += n;
-            } else if let Mult = op {
-              result *= n;
-            }
-          } else {
-            return Err(format!("Bad operand: {:?}", arg));
-          }
-        }
-        NumberAtom(result)
-      },
-      op => return Err(format!("Primitive op {:?} not implemented", op)),
-    })
-
-  }
-}
-
-impl Sexp {
-  fn print(&self) -> String {
-    use self::Sexp::*;
-    match self {
-      &BoolAtom(true) => format!("#t"),
-      &BoolAtom(false) => format!("#f"),
-      &SymbolAtom(ref sym) => format!("{}", sym),
-      &StringAtom(ref s) => format!("\"{}\"", s),
-      &NumberAtom(ref n) => format!("{}", n),
-      &Cons(ref car, ref cdr) => format!("({} . {})", car.print(), cdr.print()),
-      &Nil => format!("()"),
-      &FnLiteral { ref formal_params, .. } => format!("<lambda {:?}>", formal_params),
-      &Primitive(ref sym) => format!("<primitive \"{:?}\">", sym),
-    }
-  }
-
-  fn truthy(&self) -> bool {
-    use self::Sexp::*;
-    match self {
-      &BoolAtom(false) => false,
-      _ => true
-    }
-  }
-}
-
-fn tokenize(input: &mut Peekable<Chars>) -> Vec<Token> {
-  use self::Token::*;
-  let mut tokens = Vec::new();
-  loop {
-    match input.next() {
-      None => break,
-      Some('(') => tokens.push(LParen),
-      Some(')') => tokens.push(RParen),
-      Some('\'') => tokens.push(Quote),
-      Some(c) if c.is_whitespace() => continue,
-      Some(c) if c.is_numeric() => {
-        let tok: String = input.peeking_take_while(|next| next.is_numeric()).collect();
-        let n: u64 = format!("{}{}", c, tok).parse().unwrap();
-        tokens.push(NumLiteral(n));
-      },
-      Some('"') => {
-        let string: String = input.scan(false, |escape, cur_char| {
-          let seen_escape = *escape;
-          *escape = cur_char == '\\' && !seen_escape;
-          match (cur_char, seen_escape) {
-            ('"', false) => None,
-            ('\\', false) => Some(None),
-            (c, _) => Some(Some(c))
-          }
-        }).filter_map(|x| x).collect();
-        tokens.push(StringLiteral(string));
-      }
-      Some(c) => {
-        let sym: String = input.peeking_take_while(|next| {
-          match *next {
-            '(' | ')' => false,
-            c if c.is_whitespace() => false,
-            _ => true
-          }
-        }).collect();
-        tokens.push(Word(format!("{}{}", c, sym)));
-      }
-    }
-  }
-  tokens
-}
-
-fn parse(tokens: &mut Peekable<IntoIter<Token>>) -> Result<Sexp, String> {
-  use self::Token::*;
-  use self::Sexp::*;
-  match tokens.next() {
-    Some(Word(ref s)) if s == "#f" => Ok(BoolAtom(false)),
-    Some(Word(ref s)) if s == "#t" => Ok(BoolAtom(true)),
-    Some(Word(s)) => Ok(SymbolAtom(s)),
-    Some(StringLiteral(s)) => Ok(StringAtom(s)),
-    Some(LParen) => parse_sexp(tokens),
-    Some(RParen) => Err(format!("Unexpected ')'")),
-    Some(Quote) => {
-      let quoted = parse(tokens)?;
-      Ok(Cons(Box::new(SymbolAtom(format!("quote"))), Box::new(Cons(Box::new(quoted), Box::new(Nil)))))
-    },
-    Some(NumLiteral(n)) => Ok(NumberAtom(n)),
-    None => Err(format!("Unexpected end of input")),
-  }
-}
-
-fn parse_sexp(tokens: &mut Peekable<IntoIter<Token>>) -> Result<Sexp, String> {
-  use self::Token::*;
-  use self::Sexp::*;
-  let mut cell = Nil;
-  {
-    let mut cell_ptr = &mut cell;
-    loop {
-      match tokens.peek() {
-        None => return Err(format!("Unexpected end of input")),
-        Some(&RParen) => {
-          tokens.next();
-          break;
-        },
-        _ => {
-          let current = parse(tokens)?;
-          let new_cdr = Cons(Box::new(current), Box::new(Nil));
-          match cell_ptr {
-            &mut Cons(_, ref mut cdr) => **cdr = new_cdr,
-            &mut Nil => *cell_ptr  = new_cdr,
-            _ => unreachable!()
-          };
-
-          let old_ptr = cell_ptr;
-          let new_ptr: &mut Sexp = match old_ptr { &mut Cons(_, ref mut cdr) => cdr, _ => unreachable!() } as &mut Sexp;
-          cell_ptr = new_ptr;
-        }
-      }
-    }
-  }
-  Ok(cell)
-}
-

schala-lang/codegen/Cargo.toml

@@ -1,12 +0,0 @@
-[package]
-name = "schala-lang-codegen"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-edition = "2018"
-
-[lib]
-proc-macro = true
-
-[dependencies]
-syn = { version = "0.15.12", features = ["full", "extra-traits", "fold"] }
-quote = "0.6.8"

schala-lang/codegen/src/lib.rs

@@ -1,54 +0,0 @@
-#![feature(box_patterns)]
-#![recursion_limit="128"]
-extern crate proc_macro;
-#[macro_use]
-extern crate quote;
-#[macro_use]
-extern crate syn;
-
-use self::proc_macro::TokenStream;
-use self::syn::fold::Fold;
-
-struct RecursiveDescentFn {
-}
-
-impl Fold for RecursiveDescentFn {
-  fn fold_item_fn(&mut self, mut i: syn::ItemFn) -> syn::ItemFn {
-    let box block = i.block;
-    let ref ident = i.ident;
-
-    let new_block: syn::Block = parse_quote! {
-      {
-        let next_token_before_parse = self.token_handler.peek();
-        let record = ParseRecord {
-          production_name: stringify!(#ident).to_string(),
-          next_token: format!("{}", next_token_before_parse.to_string_with_metadata()),
-          level: self.parse_level,
-        };
-        self.parse_level += 1;
-        self.parse_record.push(record);
-        let result = { #block };
-
-        if self.parse_level != 0 {
-          self.parse_level -= 1;
-        }
-
-        result.map_err(|mut parse_error: ParseError| {
-          parse_error.production_name = Some(stringify!(#ident).to_string());
-          parse_error
-        })
-      }
-    };
-    i.block = Box::new(new_block);
-    i
-  }
-}
-
-#[proc_macro_attribute]
-pub fn recursive_descent_method(_attr: TokenStream, item: TokenStream) -> TokenStream {
-
-  let input: syn::ItemFn = parse_macro_input!(item as syn::ItemFn);
-  let mut folder = RecursiveDescentFn {};
-  let output = folder.fold_item_fn(input);
-  TokenStream::from(quote!(#output))
-}

schala-lang/language/Cargo.toml

@@ -1,20 +0,0 @@
-[package]
-name = "schala-lang"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-edition = "2018"
-
-[dependencies]
-itertools = "0.8.0"
-take_mut = "0.2.2"
-maplit = "1.0.1"
-lazy_static = "1.3.0"
-failure = "0.1.5"
-ena = "0.11.0"
-stopwatch = "0.0.7"
-derivative = "1.0.3"
-colored = "1.8"
-radix_trie = "0.1.5"
-
-schala-lang-codegen = { path = "../codegen" }
-schala-repl = { path = "../../schala-repl" }

schala-lang/language/src/ast.rs

@@ -1,307 +0,0 @@
-use std::rc::Rc;
-
-use crate::derivative::Derivative;
-
-mod walker;
-mod visitor;
-mod visitor_test;
-mod operators;
-pub use operators::*;
-pub use visitor::ASTVisitor;
-pub use walker::walk_ast;
-
-/// An abstract identifier for an AST node
-#[derive(Debug, PartialEq, Eq, Hash, Clone)]
-pub struct ItemId {
-  idx: u32,
-}
-
-impl ItemId {
-  fn new(n: u32) -> ItemId {
-    ItemId { idx: n }
-  }
-}
-
-pub struct ItemIdStore {
-  last_idx: u32
-}
-
-impl ItemIdStore {
-  pub fn new() -> ItemIdStore {
-    ItemIdStore { last_idx: 0 }
-  }
-  /// Always returns an ItemId with internal value zero
-  #[cfg(test)]
-  pub fn new_id() -> ItemId {
-    ItemId { idx: 0 }
-  }
-
-  /// This limits the size of the AST to 2^32 tree elements
-  pub fn fresh(&mut self) -> ItemId {
-    let idx = self.last_idx;
-    self.last_idx += 1;
-    ItemId::new(idx)
-  }
-}
-
-#[derive(Derivative, Debug)]
-#[derivative(PartialEq)]
-pub struct AST {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub statements: Vec<Statement>
-}
-
-#[derive(Derivative, Debug, Clone)]
-#[derivative(PartialEq)]
-pub struct Statement {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub kind: StatementKind,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum StatementKind {
-  Expression(Expression),
-  Declaration(Declaration),
-  Import(ImportSpecifier),
-  Module(ModuleSpecifier),
-}
-
-pub type Block = Vec<Statement>;
-pub type ParamName = Rc<String>;
-
-#[derive(Debug, Derivative, Clone)]
-#[derivative(PartialEq)]
-pub struct QualifiedName {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub components: Vec<Rc<String>>,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct FormalParam {
-  pub name: ParamName,
-  pub default: Option<Expression>,
-  pub anno: Option<TypeIdentifier>
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Declaration {
-  FuncSig(Signature),
-  FuncDecl(Signature, Block),
-  TypeDecl {
-    name: TypeSingletonName,
-    body: TypeBody,
-    mutable: bool
-  },
-  //TODO this needs to be more sophisticated
-  TypeAlias {
-    alias: Rc<String>,
-    original: Rc<String>,
-  },
-  Binding {
-    name: Rc<String>,
-    constant: bool,
-    type_anno: Option<TypeIdentifier>,
-    expr: Expression,
-  },
-  Impl {
-    type_name: TypeIdentifier,
-    interface_name: Option<TypeSingletonName>,
-    block: Vec<Declaration>,
-  },
-  Interface {
-    name: Rc<String>,
-    signatures: Vec<Signature>
-  }
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct Signature {
-  pub name: Rc<String>,
-  pub operator: bool,
-  pub params: Vec<FormalParam>,
-  pub type_anno: Option<TypeIdentifier>,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct TypeBody(pub Vec<Variant>);
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Variant {
-  UnitStruct(Rc<String>),
-  TupleStruct(Rc<String>, Vec<TypeIdentifier>),
-  Record {
-    name: Rc<String>,
-    members: Vec<(Rc<String>, TypeIdentifier)>,
-  }
-}
-
-#[derive(Debug, Derivative, Clone)]
-#[derivative(PartialEq)]
-pub struct Expression {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub kind: ExpressionKind,
-  pub type_anno: Option<TypeIdentifier>
-}
-
-impl Expression {
-  pub fn new(id: ItemId, kind: ExpressionKind) -> Expression {
-    Expression { id, kind, type_anno: None }
-  }
-
-  pub fn with_anno(id: ItemId, kind: ExpressionKind, type_anno: TypeIdentifier) -> Expression {
-    Expression { id, kind, type_anno: Some(type_anno) }
-  }
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum TypeIdentifier {
-  Tuple(Vec<TypeIdentifier>),
-  Singleton(TypeSingletonName)
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct TypeSingletonName {
-  pub name: Rc<String>,
-  pub params: Vec<TypeIdentifier>,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum ExpressionKind {
-  NatLiteral(u64),
-  FloatLiteral(f64),
-  StringLiteral(Rc<String>),
-  BoolLiteral(bool),
-  BinExp(BinOp, Box<Expression>, Box<Expression>),
-  PrefixExp(PrefixOp, Box<Expression>),
-  TupleLiteral(Vec<Expression>),
-  Value(QualifiedName),
-  NamedStruct {
-    name: QualifiedName,
-    fields: Vec<(Rc<String>, Expression)>,
-  },
-  Call {
-    f: Box<Expression>,
-    arguments: Vec<InvocationArgument>,
-  },
-  Index {
-    indexee: Box<Expression>,
-    indexers: Vec<Expression>,
-  },
-  IfExpression {
-    discriminator: Option<Box<Expression>>,
-    body: Box<IfExpressionBody>,
-  },
-  WhileExpression {
-    condition: Option<Box<Expression>>,
-    body: Block,
-  },
-  ForExpression {
-    enumerators: Vec<Enumerator>,
-    body: Box<ForBody>,
-  },
-  Lambda {
-    params: Vec<FormalParam>,
-    type_anno: Option<TypeIdentifier>,
-    body: Block,
-  },
-  ListLiteral(Vec<Expression>),
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum InvocationArgument {
-  Positional(Expression),
-  Keyword {
-    name: Rc<String>,
-    expr: Expression,
-  },
-  Ignored
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum IfExpressionBody {
-  SimpleConditional {
-    then_case: Block,
-    else_case: Option<Block>
-  },
-  SimplePatternMatch {
-    pattern: Pattern,
-    then_case: Block,
-    else_case: Option<Block>
-  },
-  CondList(Vec<ConditionArm>)
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct ConditionArm {
-  pub condition: Condition,
-  pub guard: Option<Expression>,
-  pub body: Block,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Condition {
-  Pattern(Pattern),
-  TruncatedOp(BinOp, Expression),
-  Expression(Expression),
-  Else,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Pattern {
-  Ignored,
-  TuplePattern(Vec<Pattern>),
-  Literal(PatternLiteral),
-  TupleStruct(QualifiedName, Vec<Pattern>),
-  Record(QualifiedName, Vec<(Rc<String>, Pattern)>),
-  VarOrName(QualifiedName),
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum PatternLiteral {
-  NumPattern {
-    neg: bool,
-    num: ExpressionKind,
-  },
-  StringPattern(Rc<String>),
-  BoolPattern(bool),
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct Enumerator {
-  pub id: Rc<String>,
-  pub generator: Expression,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum ForBody {
-  MonadicReturn(Expression),
-  StatementBlock(Block),
-}
-
-#[derive(Debug, Derivative, Clone)]
-#[derivative(PartialEq)]
-pub struct ImportSpecifier {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub path_components: Vec<Rc<String>>,
-  pub imported_names: ImportedNames
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum ImportedNames {
-  All,
-  LastOfPath,
-  List(Vec<Rc<String>>)
-}
-
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct ModuleSpecifier {
-  pub name: Rc<String>,
-  pub contents: Vec<Statement>,
-}
-

schala-lang/language/src/ast/operators.rs

@@ -1,108 +0,0 @@
-use std::rc::Rc;
-use std::str::FromStr;
-
-use crate::tokenizing::TokenKind;
-use crate::builtin::Builtin;
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct PrefixOp {
-  sigil: Rc<String>,
-  pub builtin: Option<Builtin>,
-}
-
-impl PrefixOp {
-  #[allow(dead_code)]
-  pub fn sigil(&self) -> &Rc<String> {
-    &self.sigil
-  }
-  pub fn is_prefix(op: &str) -> bool {
-    match op {
-      "+" => true,
-      "-" => true,
-      "!" => true,
-      _ => false
-    }
-  }
-}
-
-impl FromStr for PrefixOp {
-  type Err = ();
-
-  fn from_str(s: &str) -> Result<Self, Self::Err> {
-    use Builtin::*;
-
-    let builtin = match s {
-      "+" => Ok(Increment),
-      "-" => Ok(Negate),
-      "!" => Ok(BooleanNot),
-      _ => Err(())
-    };
-
-    builtin.map(|builtin| PrefixOp { sigil: Rc::new(s.to_string()), builtin: Some(builtin) })
-  }
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct BinOp {
-  sigil: Rc<String>,
-  pub builtin: Option<Builtin>,
-}
-
-impl BinOp {
-  pub fn from_sigil(sigil: &str) -> BinOp {
-    let builtin = Builtin::from_str(sigil).ok();
-    BinOp { sigil: Rc::new(sigil.to_string()), builtin }
-  }
-  pub fn sigil(&self) -> &Rc<String> {
-    &self.sigil
-  }
-  pub fn from_sigil_token(tok: &TokenKind) -> Option<BinOp> {
-    let s = token_kind_to_sigil(tok)?;
-    Some(BinOp::from_sigil(s))
-  }
-
-  pub fn min_precedence() -> i32 {
-    i32::min_value()
-  }
-  pub fn get_precedence_from_token(op_tok: &TokenKind) -> Option<i32> {
-    let s = token_kind_to_sigil(op_tok)?;
-    Some(binop_precedences(s))
-  }
-}
-
-fn token_kind_to_sigil<'a>(tok: &'a TokenKind) -> Option<&'a str> {
-  use self::TokenKind::*;
-  Some(match tok {
-    Operator(op) => op.as_str(),
-    Period => ".",
-    Pipe => "|",
-    Slash => "/",
-    LAngleBracket => "<",
-    RAngleBracket => ">",
-    Equals => "=",
-    _ => return None
-  })
-}
-
-fn binop_precedences(s: &str) -> i32 {
-  let default = 10_000_000;
-  match s {
-    "+" => 10,
-    "-" => 10,
-    "*" =>  20,
-    "/" =>  20,
-    "%" =>  20,
-    "++" => 30,
-    "^" =>  30,
-    "&" =>  20,
-    "|" => 20,
-    ">" => 20,
-    ">=" => 20,
-    "<" =>  20,
-    "<=" => 20,
-    "==" => 40,
-    "=" =>  10,
-    "<=>" => 30,
-    _ => default,
-  }
-}

schala-lang/language/src/ast/visitor.rs

@@ -1,41 +0,0 @@
-use std::rc::Rc;
-use crate::ast::*;
-
-//TODO maybe these functions should take closures that return a KeepRecursing | StopHere type,
-//or a tuple of (T, <that type>)
-
-pub trait ASTVisitor: Sized {
-  fn ast(&mut self, _ast: &AST) {}
-  fn block(&mut self, _statements: &Vec<Statement>) {}
-  fn statement(&mut self, _statement: &Statement) {}
-  fn declaration(&mut self, _declaration: &Declaration) {}
-  fn signature(&mut self, _signature: &Signature) {}
-  fn type_declaration(&mut self, _name: &TypeSingletonName, _body: &TypeBody, _mutable: bool) {}
-  fn type_alias(&mut self, _alias: &Rc<String>, _original: &Rc<String>) {}
-  fn binding(&mut self, _name: &Rc<String>, _constant: bool, _type_anno: Option<&TypeIdentifier>, _expr: &Expression) {}
-  fn implemention(&mut self, _type_name: &TypeIdentifier, _interface_name: Option<&TypeSingletonName>, _block: &Vec<Declaration>) {}
-  fn interface(&mut self, _name: &Rc<String>, _signatures: &Vec<Signature>) {}
-  fn expression(&mut self, _expression: &Expression) {}
-  fn expression_kind(&mut self, _kind: &ExpressionKind) {}
-  fn type_annotation(&mut self, _type_anno: Option<&TypeIdentifier>) {}
-  fn named_struct(&mut self, _name: &QualifiedName, _fields: &Vec<(Rc<String>, Expression)>) {}
-  fn call(&mut self, _f: &Expression, _arguments: &Vec<InvocationArgument>) {}
-  fn index(&mut self, _indexee: &Expression, _indexers: &Vec<Expression>) {}
-  fn if_expression(&mut self, _discrim: Option<&Expression>, _body: &IfExpressionBody) {}
-  fn condition_arm(&mut self, _arm: &ConditionArm) {}
-  fn while_expression(&mut self, _condition: Option<&Expression>, _body: &Block) {}
-  fn for_expression(&mut self, _enumerators: &Vec<Enumerator>, _body: &ForBody) {}
-  fn lambda(&mut self, _params: &Vec<FormalParam>, _type_anno: Option<&TypeIdentifier>, _body: &Block) {}
-  fn invocation_argument(&mut self, _arg: &InvocationArgument) {}
-  fn formal_param(&mut self, _param: &FormalParam) {}
-  fn import(&mut self, _import: &ImportSpecifier) {}
-  fn module(&mut self, _module: &ModuleSpecifier) {}
-  fn qualified_name(&mut self, _name: &QualifiedName) {}
-  fn nat_literal(&mut self, _n: u64) {}
-  fn float_literal(&mut self, _f: f64) {}
-  fn string_literal(&mut self, _s: &Rc<String>) {}
-  fn bool_literal(&mut self, _b: bool) {}
-  fn binexp(&mut self, _op: &BinOp, _lhs: &Expression, _rhs: &Expression) {}
-  fn prefix_exp(&mut self, _op: &PrefixOp, _arg: &Expression) {}
-  fn pattern(&mut self, _pat: &Pattern) {}
-}

schala-lang/language/src/ast/visitor_test.rs

@@ -1,41 +0,0 @@
-#![cfg(test)]
-
-use crate::ast::visitor::ASTVisitor;
-use crate::ast::walker;
-use crate::util::quick_ast;
-
-struct Tester {
-  count: u64,
-  float_count: u64
-}
-
-impl ASTVisitor for Tester {
-  fn nat_literal(&mut self, _n: u64) {
-    self.count += 1;
-  }
-  fn float_literal(&mut self, _f: f64) {
-    self.float_count += 1;
-  }
-}
-
-
-#[test]
-fn foo() {
-  let mut tester = Tester { count: 0, float_count: 0 };
-  let (ast, _) = quick_ast(r#"
-import gragh
-
-let a = 20 + 84
-let b = 28 + 1 + 2 + 2.0
-fn heh() {
-  let m = 9
-
-}
-
-"#);
-
-  walker::walk_ast(&mut tester, &ast);
-
-  assert_eq!(tester.count, 6);
-  assert_eq!(tester.float_count, 1);
-}

schala-lang/language/src/ast/walker.rs

@@ -1,269 +0,0 @@
-#![allow(dead_code)]
-use std::rc::Rc;
-use crate::ast::*;
-use crate::ast::visitor::ASTVisitor;
-use crate::util::deref_optional_box;
-
-pub fn walk_ast<V: ASTVisitor>(v: &mut V, ast: &AST) {
-  v.ast(ast);
-  walk_block(v, &ast.statements);
-}
-
-fn walk_block<V: ASTVisitor>(v: &mut V, block: &Vec<Statement>) {
-  for s in block {
-    v.statement(s);
-    statement(v, s);
-  }
-}
-
-fn statement<V: ASTVisitor>(v: &mut V, statement: &Statement) {
-  use StatementKind::*;
-  match statement.kind {
-    Expression(ref expr) => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    Declaration(ref decl) => {
-      v.declaration(decl);
-      declaration(v, decl);
-    },
-    Import(ref import_spec) => v.import(import_spec),
-    Module(ref module_spec) => {
-      v.module(module_spec);
-      walk_block(v, &module_spec.contents);
-    }
-  }
-}
-
-fn declaration<V: ASTVisitor>(v: &mut V, decl: &Declaration) {
-  use Declaration::*;
-  match decl {
-    FuncSig(sig) => {
-      v.signature(&sig);
-      signature(v, &sig);
-    },
-    FuncDecl(sig, block) => {
-      v.signature(&sig);
-      v.block(&block);
-      walk_block(v, block);
-    },
-    TypeDecl { name, body, mutable  } => v.type_declaration(name, body, *mutable),
-    TypeAlias { alias, original} => v.type_alias(alias, original), 
-    Binding { name, constant, type_anno, expr } => {
-      v.binding(name, *constant, type_anno.as_ref(), expr);
-      v.type_annotation(type_anno.as_ref());
-      v.expression(&expr);
-      expression(v, &expr);
-    },
-    Impl { type_name, interface_name, block } => {
-      v.implemention(type_name, interface_name.as_ref(), block);
-    }
-    Interface { name, signatures } => v.interface(name, signatures),
-  }
-}
-
-fn signature<V: ASTVisitor>(v: &mut V, signature: &Signature) {
-  for p in signature.params.iter() {
-    v.formal_param(p);
-  }
-  v.type_annotation(signature.type_anno.as_ref());
-  for p in signature.params.iter() {
-    formal_param(v, p);
-  }
-}
-
-fn expression<V: ASTVisitor>(v: &mut V, expression: &Expression) {
-  v.expression_kind(&expression.kind);
-  v.type_annotation(expression.type_anno.as_ref());
-  expression_kind(v, &expression.kind);
-}
-
-
-fn call<V: ASTVisitor>(v: &mut V, f: &Expression, args: &Vec<InvocationArgument>) {
-  v.expression(f);
-  expression(v, f);
-  for arg in args.iter() {
-    v.invocation_argument(arg);
-    invocation_argument(v, arg);
-  }
-}
-
-fn invocation_argument<V: ASTVisitor>(v: &mut V, arg: &InvocationArgument) {
-  use InvocationArgument::*;
-  match arg {
-    Positional(expr) => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    Keyword { expr, .. } => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    Ignored => (),
-  }
-}
-
-fn index<V: ASTVisitor>(v: &mut V, indexee: &Expression, indexers: &Vec<Expression>) {
-  v.expression(indexee);
-  for i in indexers.iter() {
-    v.expression(i);
-  }
-}
-
-fn named_struct<V: ASTVisitor>(v: &mut V, n: &QualifiedName, fields: &Vec<(Rc<String>, Expression)>) {
-  v.qualified_name(n);
-  for (_, expr) in fields.iter() {
-    v.expression(expr);
-  }
-}
-
-fn lambda<V: ASTVisitor>(v: &mut V, params: &Vec<FormalParam>, type_anno: Option<&TypeIdentifier>, body: &Block) {
-  for param in params {
-    v.formal_param(param);
-    formal_param(v, param);
-  }
-  v.type_annotation(type_anno);
-  v.block(body);
-  walk_block(v, body);
-}
-
-fn formal_param<V: ASTVisitor>(v: &mut V, param: &FormalParam) {
-  param.default.as_ref().map(|p| {
-    v.expression(p);
-    expression(v, p);
-  });
-  v.type_annotation(param.anno.as_ref());
-}
-
-fn expression_kind<V: ASTVisitor>(v: &mut V, expression_kind: &ExpressionKind) {
-  use ExpressionKind::*;
-  match expression_kind {
-    NatLiteral(n) => v.nat_literal(*n),
-    FloatLiteral(f) => v.float_literal(*f),
-    StringLiteral(s) => v.string_literal(s),
-    BoolLiteral(b) => v.bool_literal(*b),
-    BinExp(op, lhs, rhs) => {
-      v.binexp(op, lhs, rhs);
-      expression(v, lhs);
-      expression(v, rhs);
-    },
-    PrefixExp(op, arg) => {
-      v.prefix_exp(op, arg);
-      expression(v, arg);
-    }
-    TupleLiteral(exprs) => {
-      for expr in exprs {
-        v.expression(expr);
-        expression(v, expr);
-      }
-    },
-    Value(name) => v.qualified_name(name),
-    NamedStruct { name, fields } => {
-      v.named_struct(name, fields);
-      named_struct(v, name, fields);
-    }
-    Call { f, arguments } => {
-      v.call(f, arguments);
-      call(v, f, arguments);
-    },
-    Index { indexee, indexers } => {
-      v.index(indexee, indexers);
-      index(v, indexee, indexers);
-    },
-    IfExpression { discriminator, body } => {
-      v.if_expression(deref_optional_box(discriminator), body);
-      discriminator.as_ref().map(|d| expression(v, d));
-      if_expression_body(v, body);
-    },
-    WhileExpression { condition, body } => v.while_expression(deref_optional_box(condition), body),
-    ForExpression { enumerators, body } => v.for_expression(enumerators, body),
-    Lambda { params , type_anno, body } => {
-      v.lambda(params, type_anno.as_ref(), body);
-      lambda(v, params, type_anno.as_ref(), body);
-    },
-    ListLiteral(exprs) => {
-      for expr in exprs {
-        v.expression(expr);
-        expression(v, expr);
-      }
-    },
-  }
-}
-
-fn if_expression_body<V: ASTVisitor>(v: &mut V, body: &IfExpressionBody) {
-  use IfExpressionBody::*;
-  match body {
-    SimpleConditional { then_case, else_case } => {
-      walk_block(v, then_case);
-      else_case.as_ref().map(|block| walk_block(v, block));
-    },
-    SimplePatternMatch { pattern, then_case, else_case } => {
-      v.pattern(pattern);
-      walk_pattern(v, pattern);
-      walk_block(v, then_case);
-      else_case.as_ref().map(|block| walk_block(v, block));
-    },
-    CondList(arms) => {
-      for arm in arms {
-        v.condition_arm(arm);
-        condition_arm(v, arm);
-      }
-    }
-  }
-}
-
-fn condition_arm<V: ASTVisitor>(v: &mut V, arm: &ConditionArm) {
-  use Condition::*;
-  v.condition_arm(arm);
-  match arm.condition {
-    Pattern(ref pat) => {
-      v.pattern(pat);
-      walk_pattern(v, pat);
-    },
-    TruncatedOp(ref _binop, ref expr) => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    Expression(ref expr) => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    _ => ()
-  }
-  arm.guard.as_ref().map(|guard| {
-    v.expression(guard);
-    expression(v, guard);
-  });
-  v.block(&arm.body);
-  walk_block(v, &arm.body);
-}
-
-fn walk_pattern<V: ASTVisitor>(v: &mut V, pat: &Pattern) {
-  use Pattern::*;
-  match pat {
-    TuplePattern(patterns) => {
-      for pat in patterns {
-        v.pattern(pat);
-        walk_pattern(v, pat);
-      }
-    },
-    TupleStruct(qualified_name, patterns) => {
-      v.qualified_name(qualified_name);
-      for pat in patterns {
-        v.pattern(pat);
-        walk_pattern(v, pat);
-      }
-    },
-    Record(qualified_name, name_and_patterns) => {
-      v.qualified_name(qualified_name);
-      for (_, pat) in name_and_patterns {
-        v.pattern(pat);
-        walk_pattern(v, pat);
-      }
-    },
-    VarOrName(qualified_name) => {
-      v.qualified_name(qualified_name);
-    },
-    _ => ()
-  }
-}

schala-lang/language/src/builtin.rs

@@ -1,102 +0,0 @@
-use std::str::FromStr;
-
-use crate::typechecking::{TypeConst, Type};
-
-#[derive(Debug, Clone, Copy, PartialEq)]
-pub enum Builtin {
-  Add,
-  Increment,
-  Subtract,
-  Negate,
-  Multiply,
-  Divide,
-  Quotient,
-  Modulo,
-  Exponentiation,
-  BitwiseAnd,
-  BitwiseOr,
-  BooleanAnd,
-  BooleanOr,
-  BooleanNot,
-  Equality,
-  LessThan,
-  LessThanOrEqual,
-  GreaterThan,
-  GreaterThanOrEqual,
-  Comparison,
-  FieldAccess,
-  IOPrint,
-  IOPrintLn,
-  IOGetLine,
-  Assignment,
-  Concatenate,
-}
-
-impl Builtin {
-  pub fn get_type(&self) -> Type {
-    use Builtin::*;
-    match self {
-      Add => ty!(Nat -> Nat -> Nat),
-      Subtract => ty!(Nat -> Nat -> Nat),
-      Multiply => ty!(Nat -> Nat -> Nat),
-      Divide => ty!(Nat -> Nat -> Float),
-      Quotient => ty!(Nat -> Nat -> Nat),
-      Modulo => ty!(Nat -> Nat -> Nat),
-      Exponentiation => ty!(Nat -> Nat -> Nat),
-      BitwiseAnd => ty!(Nat -> Nat -> Nat),
-      BitwiseOr => ty!(Nat -> Nat -> Nat),
-      BooleanAnd => ty!(Bool -> Bool -> Bool),
-      BooleanOr => ty!(Bool -> Bool -> Bool),
-      BooleanNot => ty!(Bool -> Bool),
-      Equality => ty!(Nat -> Nat -> Bool),
-      LessThan => ty!(Nat -> Nat -> Bool),
-      LessThanOrEqual => ty!(Nat -> Nat -> Bool),
-      GreaterThan => ty!(Nat -> Nat -> Bool),
-      GreaterThanOrEqual => ty!(Nat -> Nat -> Bool),
-      Comparison => ty!(Nat -> Nat -> Ordering),
-      FieldAccess => ty!(Unit),
-      IOPrint => ty!(Unit),
-      IOPrintLn => ty!(Unit) ,
-      IOGetLine => ty!(StringT),
-      Assignment => ty!(Unit),
-      Concatenate => ty!(StringT -> StringT -> StringT),
-      Increment => ty!(Nat -> Int),
-      Negate => ty!(Nat -> Int)
-    }
-  }
-}
-
-impl FromStr for Builtin {
-  type Err = ();
-
-  fn from_str(s: &str) -> Result<Self, Self::Err> {
-    use Builtin::*;
-    Ok(match s {
-      "+" => Add,
-      "-" => Subtract,
-      "*" => Multiply,
-      "/" => Divide,
-      "quot" => Quotient,
-      "%" => Modulo,
-      "++" => Concatenate,
-      "^" =>  Exponentiation,
-      "&" => BitwiseAnd,
-      "&&" => BooleanAnd,
-      "|" => BitwiseOr,
-      "||" => BooleanOr,
-      "!" => BooleanNot,
-      ">" => GreaterThan,
-      ">=" => GreaterThanOrEqual,
-      "<" => LessThan,
-      "<=" => LessThanOrEqual,
-      "==" => Equality,
-      "=" => Assignment,
-      "<=>" => Comparison,
-      "." => FieldAccess,
-      "print" => IOPrint,
-      "println" => IOPrintLn,
-      "getline" => IOGetLine,
-      _ => return Err(())
-    })
-  }
-}

schala-lang/language/src/debugging.rs

@@ -1,10 +0,0 @@
-use crate::ast::*;
-
-impl AST {
-  pub fn compact_debug(&self) -> String {
-    format!("{:?}", self)
-  }
-  pub fn expanded_debug(&self) -> String {
-    format!("{:#?}", self)
-  }
-}

schala-lang/language/src/eval.rs

@@ -1,455 +0,0 @@
-use std::rc::Rc;
-use std::fmt::Write;
-use std::io;
-
-use itertools::Itertools;
-
-use crate::schala::SymbolTableHandle;
-use crate::util::ScopeStack;
-use crate::reduced_ast::{BoundVars, ReducedAST, Stmt, Expr, Lit, Func, Alternative, Subpattern};
-use crate::symbol_table::{SymbolSpec, Symbol, SymbolTable, FullyQualifiedSymbolName};
-use crate::builtin::Builtin;
-
-mod test;
-
-pub struct State<'a> {
-  values: ScopeStack<'a, Rc<String>, ValueEntry>,
-}
-
-impl<'a> State<'a> {
-  pub fn new() -> State<'a> {
-    let values = ScopeStack::new(Some(format!("global")));
-    State { values }
-  }
-
-  pub fn debug_print(&self) -> String {
-    format!("Values: {:?}", self.values)
-  }
-
-  fn new_frame(&'a self, items: &'a Vec<Node>, bound_vars: &BoundVars) -> State<'a> {
-    let mut inner_state = State {
-      values: self.values.new_scope(None),
-    };
-    for (bound_var, val) in bound_vars.iter().zip(items.iter()) {
-      if let Some(bv) = bound_var.as_ref() {
-        inner_state.values.insert(bv.clone(), ValueEntry::Binding { constant: true, val: val.clone() });
-      }
-    }
-    inner_state
-  }
-}
-
-#[derive(Debug, Clone)]
-enum Node {
-  Expr(Expr),
-  PrimObject {
-    name: Rc<String>,
-    tag: usize,
-    items: Vec<Node>,
-  },
-  PrimTuple {
-    items: Vec<Node>
-  }
-}
-
-fn paren_wrapped_vec(terms: impl Iterator<Item=String>) -> String {
-  let mut buf = String::new();
-  write!(buf, "(").unwrap();
-  for term in terms.map(|e| Some(e)).intersperse(None) {
-    match term {
-      Some(e) => write!(buf, "{}", e).unwrap(),
-      None => write!(buf, ", ").unwrap(),
-    };
-  }
-  write!(buf, ")").unwrap();
-  buf
-}
-
-
-impl Node {
-  fn to_repl(&self) -> String {
-    match self {
-      Node::Expr(e) => e.to_repl(),
-      Node::PrimObject { name, items, .. } if items.len() == 0 => format!("{}", name),
-      Node::PrimObject { name, items, .. } => format!("{}{}", name, paren_wrapped_vec(items.iter().map(|x| x.to_repl()))),
-      Node::PrimTuple { items } => format!("{}", paren_wrapped_vec(items.iter().map(|x| x.to_repl()))),
-    }
-  }
-  fn is_true(&self) -> bool {
-    match self {
-      Node::Expr(Expr::Lit(crate::reduced_ast::Lit::Bool(true))) => true,
-      _ => false,
-    }
-  }
-}
-
-#[derive(Debug)]
-enum ValueEntry {
-  Binding {
-    constant: bool,
-    val: /*FullyEvaluatedExpr*/ Node, //TODO make this use a subtype to represent fully evaluatedness
-  }
-}
-
-type EvalResult<T> = Result<T, String>;
-
-impl Expr {
-  fn to_node(self) -> Node {
-    Node::Expr(self)
-  }
-  fn to_repl(&self) -> String {
-    use self::Lit::*;
-    use self::Func::*;
-
-    match self {
-      Expr::Lit(ref l) => match l {
-        Nat(n) => format!("{}", n),
-        Int(i) => format!("{}", i),
-        Float(f) => format!("{}", f),
-        Bool(b) => format!("{}", b),
-        StringLit(s) => format!("\"{}\"", s),
-      },
-      Expr::Func(f) => match f {
-        BuiltIn(builtin) => format!("<built-in function '{:?}'>", builtin),
-        UserDefined { name: None, .. } => format!("<function>"),
-        UserDefined { name: Some(name), .. } => format!("<function '{}'>", name),
-      },
-      Expr::Constructor { type_name, arity, .. } => {
-        format!("<constructor for `{}` arity {}>", type_name, arity)
-      },
-      Expr::Tuple(exprs) => paren_wrapped_vec(exprs.iter().map(|x| x.to_repl())),
-      _ => format!("{:?}", self),
-    }
-  }
-
-  fn replace_conditional_target_sigil(self, replacement: &Expr) -> Expr {
-    use self::Expr::*;
-
-    match self {
-      ConditionalTargetSigilValue => replacement.clone(),
-      Unit | Lit(_) | Func(_) | Sym(_) | Constructor { .. } |
-       CaseMatch { .. } | UnimplementedSigilValue | ReductionError(_) => self,
-      Tuple(exprs) => Tuple(exprs.into_iter().map(|e| e.replace_conditional_target_sigil(replacement)).collect()),
-      Call { f, args } => {
-        let new_args = args.into_iter().map(|e| e.replace_conditional_target_sigil(replacement)).collect();
-        Call { f, args: new_args }
-      },
-      Conditional { .. } => panic!("Dunno if I need this, but if so implement"),
-      Assign { .. } => panic!("I'm pretty sure I don't need this"),
-    }
-  }
-}
-
-impl<'a> State<'a> {
-  pub fn evaluate(&mut self, ast: ReducedAST, repl: bool) -> Vec<Result<String, String>> {
-    let mut acc = vec![];
-
-    // handle prebindings
-    for statement in ast.0.iter() {
-      self.prebinding(statement);
-    }
-
-    for statement in ast.0 {
-      match self.statement(statement) {
-        Ok(Some(ref output)) if repl => {
-          acc.push(Ok(output.to_repl()))
-        },
-        Ok(_) => (),
-        Err(error) => {
-          acc.push(Err(format!("Runtime error: {}", error)));
-          return acc;
-        },
-      }
-    }
-    acc
-  }
-
-  fn prebinding(&mut self, stmt: &Stmt) {
-    match stmt {
-      Stmt::PreBinding { name, func } => {
-        let v_entry = ValueEntry::Binding { constant: true, val: Node::Expr(Expr::Func(func.clone())) };
-        self.values.insert(name.clone(), v_entry);
-      },
-      Stmt::Expr(_expr) => {
-        //TODO have this support things like nested function defs
-
-      },
-      _ => ()
-    }
-  }
-
-  fn statement(&mut self, stmt: Stmt) -> EvalResult<Option<Node>> {
-    match stmt {
-      Stmt::Binding { name, constant, expr } => {
-        let val = self.expression(Node::Expr(expr))?;
-        self.values.insert(name.clone(), ValueEntry::Binding { constant, val });
-        Ok(None)
-      },
-      Stmt::Expr(expr) => Ok(Some(self.expression(expr.to_node())?)),
-      Stmt::PreBinding {..} | Stmt::Noop => Ok(None),
-    }
-  }
-
-  fn block(&mut self, stmts: Vec<Stmt>) -> EvalResult<Node> {
-    let mut ret = None;
-    for stmt in stmts {
-      ret = self.statement(stmt)?;
-    }
-    Ok(ret.unwrap_or(Node::Expr(Expr::Unit)))
-  }
-
-  fn expression(&mut self, node: Node) -> EvalResult<Node> {
-    use self::Expr::*;
-    match node {
-      t @ Node::PrimTuple { .. } => Ok(t),
-      obj @ Node::PrimObject { .. } =>  Ok(obj),
-      Node::Expr(expr) => match expr {
-        literal @ Lit(_) => Ok(Node::Expr(literal)),
-        Call { box f, args } => self.call_expression(f, args),
-        Sym(name) => Ok(match self.values.lookup(&name) {
-          Some(ValueEntry::Binding { val, .. }) => val.clone(),
-          None => return Err(format!("Could not look up symbol {}", name))
-        }),
-        Constructor { arity, ref name, tag, .. } if arity == 0 => Ok(Node::PrimObject { name: name.clone(), tag, items: vec![] }),
-        constructor @ Constructor { .. } => Ok(Node::Expr(constructor)),
-        func @ Func(_) => Ok(Node::Expr(func)),
-        Tuple(exprs) => {
-          let nodes = exprs.into_iter().map(|expr| self.expression(Node::Expr(expr))).collect::<Result<Vec<Node>,_>>()?;
-          Ok(Node::PrimTuple { items: nodes })
-        },
-        Conditional { box cond, then_clause, else_clause } => self.conditional(cond, then_clause, else_clause),
-        Assign { box val, box expr } => self.assign_expression(val, expr),
-        Unit => Ok(Node::Expr(Unit)),
-        CaseMatch { box cond, alternatives } => self.case_match_expression(cond, alternatives),
-        ConditionalTargetSigilValue => Ok(Node::Expr(ConditionalTargetSigilValue)),
-        UnimplementedSigilValue => Err(format!("Sigil value eval not implemented")),
-        ReductionError(err) => Err(format!("Reduction error: {}", err)),
-      }
-    }
-  }
-
-  fn call_expression(&mut self, f: Expr, args: Vec<Expr>) -> EvalResult<Node> {
-    use self::Expr::*;
-    match self.expression(Node::Expr(f))? {
-      Node::Expr(Constructor { type_name, name, tag, arity }) => self.apply_data_constructor(type_name, name, tag, arity, args),
-      Node::Expr(Func(f)) => self.apply_function(f, args),
-      other => return Err(format!("Tried to call {:?} which is not a function or data constructor", other)),
-    }
-  }
-
-  fn apply_data_constructor(&mut self, _type_name: Rc<String>, name: Rc<String>, tag: usize, arity: usize, args: Vec<Expr>) -> EvalResult<Node> {
-    if arity != args.len() {
-      return Err(format!("Data constructor {} requires {} arg(s)", name, arity));
-    }
-
-    let evaled_args = args.into_iter().map(|expr| self.expression(Node::Expr(expr))).collect::<Result<Vec<Node>,_>>()?;
-    //let evaled_args = vec![];
-    Ok(Node::PrimObject {
-      name: name.clone(),
-      items: evaled_args,
-      tag 
-    })
-  }
-
-  fn apply_function(&mut self, f: Func, args: Vec<Expr>) -> EvalResult<Node> {
-    match f {
-      Func::BuiltIn(builtin) => Ok(self.apply_builtin(builtin, args)?),
-      Func::UserDefined { params, body, name } => {
-
-        if params.len() != args.len() {
-          return Err(format!("calling a {}-argument function with {} args", params.len(), args.len()))
-        }
-        let mut func_state = State {
-          values: self.values.new_scope(name.map(|n| format!("{}", n))),
-        };
-        for (param, val) in params.into_iter().zip(args.into_iter()) {
-          let val = func_state.expression(Node::Expr(val))?;
-          func_state.values.insert(param, ValueEntry::Binding { constant: true, val });
-        }
-        // TODO figure out function return semantics
-        func_state.block(body)
-      }
-    }
-  }
-
-  fn apply_builtin(&mut self, builtin: Builtin, args: Vec<Expr>) -> EvalResult<Node> {
-    use self::Expr::*;
-    use self::Lit::*;
-    use Builtin::*;
-
-    let evaled_args: Result<Vec<Node>, String> = args.into_iter().map(|arg| self.expression(arg.to_node()))
-      .collect();
-    let evaled_args = evaled_args?;
-
-    Ok(match (builtin, evaled_args.as_slice()) {
-      (FieldAccess, &[Node::PrimObject { .. }]) => {
-        //TODO implement field access
-        unimplemented!()
-      },
-      (binop, &[Node::Expr(ref lhs), Node::Expr(ref rhs)]) => match (binop, lhs, rhs) {
-        /* binops */
-        (Add, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l + r)),
-        (Concatenate, Lit(StringLit(ref s1)), Lit(StringLit(ref s2))) => Lit(StringLit(Rc::new(format!("{}{}", s1, s2)))),
-        (Subtract, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l - r)),
-        (Multiply, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l * r)),
-        (Divide, Lit(Nat(l)), Lit(Nat(r))) => Lit(Float((*l as f64)/ (*r as f64))),
-        (Quotient, Lit(Nat(l)), Lit(Nat(r))) => if *r == 0 {
-          return Err(format!("divide by zero"));
-        } else {
-          Lit(Nat(l / r))
-        },
-        (Modulo, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l % r)),
-        (Exponentiation, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l ^ r)),
-        (BitwiseAnd, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l & r)),
-        (BitwiseOr, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l | r)),
-
-        /* comparisons */
-        (Equality, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l == r)),
-        (Equality, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l == r)),
-        (Equality, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l == r)),
-        (Equality, Lit(Bool(l)), Lit(Bool(r))) => Lit(Bool(l == r)),
-        (Equality, Lit(StringLit(ref l)), Lit(StringLit(ref r))) => Lit(Bool(l == r)),
-
-        (LessThan, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l < r)),
-        (LessThan, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l < r)),
-        (LessThan, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l < r)),
-
-        (LessThanOrEqual, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l <= r)),
-        (LessThanOrEqual, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l <= r)),
-        (LessThanOrEqual, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l <= r)),
-
-        (GreaterThan, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l > r)),
-        (GreaterThan, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l > r)),
-        (GreaterThan, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l > r)),
-
-        (GreaterThanOrEqual, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l >= r)),
-        (GreaterThanOrEqual, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l >= r)),
-        (GreaterThanOrEqual, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l >= r)),
-        _ => return Err("No valid binop".to_string())
-      }.to_node(),
-      (prefix, &[Node::Expr(ref arg)]) => match (prefix, arg) {
-        (BooleanNot, Lit(Bool(true))) => Lit(Bool(false)),
-        (BooleanNot, Lit(Bool(false))) => Lit(Bool(true)),
-        (Negate, Lit(Nat(n))) => Lit(Int(-1*(*n as i64))),
-        (Negate, Lit(Int(n))) => Lit(Int(-1*(*n as i64))),
-        (Increment, Lit(Int(n))) => Lit(Int(*n)),
-        (Increment, Lit(Nat(n))) => Lit(Nat(*n)),
-        _ => return Err("No valid prefix op".to_string())
-      }.to_node(),
-
-      /* builtin functions */
-      (IOPrint, &[ref anything]) => {
-        print!("{}", anything.to_repl());
-        Expr::Unit.to_node()
-      },
-      (IOPrintLn, &[ref anything]) => {
-        println!("{}", anything.to_repl());
-        Expr::Unit.to_node()
-      },
-      (IOGetLine, &[]) => {
-        let mut buf = String::new();
-        io::stdin().read_line(&mut buf).expect("Error readling line in 'getline'");
-        Lit(StringLit(Rc::new(buf.trim().to_string()))).to_node()
-      },
-      (x, args) => return Err(format!("bad or unimplemented builtin {:?} | {:?}", x, args)),
-    })
-  }
-
-  fn conditional(&mut self, cond: Expr, then_clause: Vec<Stmt>, else_clause: Vec<Stmt>) -> EvalResult<Node> {
-    let cond = self.expression(Node::Expr(cond))?;
-    Ok(match cond {
-      Node::Expr(Expr::Lit(Lit::Bool(true))) =>  self.block(then_clause)?,
-      Node::Expr(Expr::Lit(Lit::Bool(false))) => self.block(else_clause)?,
-      _ => return Err(format!("Conditional with non-boolean condition"))
-    })
-  }
-
-  fn assign_expression(&mut self, val: Expr, expr: Expr) -> EvalResult<Node> {
-    let name = match val  {
-      Expr::Sym(name) => name,
-      _ => return Err(format!("Trying to assign to a non-value")),
-    };
-
-    let constant = match self.values.lookup(&name) {
-      None => return Err(format!("Constant {} is undefined", name)),
-      Some(ValueEntry::Binding { constant, .. }) => constant.clone(),
-    };
-    if constant {
-      return Err(format!("trying to update {}, a non-mutable binding", name));
-    }
-    let val = self.expression(Node::Expr(expr))?;
-    self.values.insert(name.clone(), ValueEntry::Binding { constant: false, val });
-    Ok(Node::Expr(Expr::Unit))
-  }
-
-  fn guard_passes(&mut self, guard: &Option<Expr>, cond: &Node) -> EvalResult<bool> {
-    if let Some(ref guard_expr) = guard {
-      let guard_expr = match cond {
-        Node::Expr(ref e) => guard_expr.clone().replace_conditional_target_sigil(e),
-        _ => guard_expr.clone()
-      };
-      Ok(self.expression(guard_expr.to_node())?.is_true())
-    } else {
-      Ok(true)
-    }
-  }
-
-  fn case_match_expression(&mut self, cond: Expr, alternatives: Vec<Alternative>) -> EvalResult<Node> {
-
-    //TODO need to handle recursive subpatterns
-    let all_subpatterns_pass = |state: &mut State, subpatterns: &Vec<Option<Subpattern>>, items: &Vec<Node>| -> EvalResult<bool> {
-
-      if subpatterns.len() == 0 {
-        return Ok(true)
-      }
-
-      if items.len() != subpatterns.len() {
-        return Err(format!("Subpattern length isn't correct items {} subpatterns {}", items.len(), subpatterns.len()));
-      }
-
-      for (maybe_subp, cond) in subpatterns.iter().zip(items.iter()) {
-        if let Some(subp) = maybe_subp {
-          if !state.guard_passes(&subp.guard, &cond)? {
-            return Ok(false)
-          }
-        }
-      }
-      Ok(true)
-    };
-
-    let cond = self.expression(Node::Expr(cond))?;
-    for alt in alternatives {
-      // no matter what type of condition we have, ignore alternative if the guard evaluates false
-      if !self.guard_passes(&alt.matchable.guard, &cond)? {
-        continue;
-      }
-
-      match cond {
-        Node::PrimObject { ref tag, ref items, .. } => {
-          if alt.matchable.tag.map(|t| t == *tag).unwrap_or(true) {
-            let mut inner_state = self.new_frame(items, &alt.matchable.bound_vars);
-            if all_subpatterns_pass(&mut inner_state, &alt.matchable.subpatterns, items)? {
-              return inner_state.block(alt.item);
-            } else {
-              continue;
-            }
-          }
-        },
-        Node::PrimTuple { ref items } =>  {
-          let mut inner_state = self.new_frame(items, &alt.matchable.bound_vars);
-          if all_subpatterns_pass(&mut inner_state, &alt.matchable.subpatterns, items)? {
-            return inner_state.block(alt.item);
-          } else {
-            continue;
-          }
-        },
-        Node::Expr(ref _e) => {
-          if let None = alt.matchable.tag {
-            return self.block(alt.item)
-          }
-        }
-      }
-    }
-    Err(format!("{:?} failed pattern match", cond))
-  }
-}

schala-lang/language/src/eval/test.rs

@@ -1,269 +0,0 @@
-#![cfg(test)]
-
-use std::cell::RefCell;
-use std::rc::Rc;
-
-use crate::symbol_table::SymbolTable;
-use crate::scope_resolution::ScopeResolver;
-use crate::reduced_ast::reduce;
-use crate::eval::State;
-
-fn evaluate_all_outputs(input: &str) -> Vec<Result<String, String>> {
-  let (mut ast, source_map) = crate::util::quick_ast(input);
-  let source_map = Rc::new(RefCell::new(source_map));
-  let symbol_table = Rc::new(RefCell::new(SymbolTable::new(source_map)));
-  symbol_table.borrow_mut().add_top_level_symbols(&ast).unwrap();
-  {
-  let mut scope_resolver = ScopeResolver::new(symbol_table.clone());
-  let _ = scope_resolver.resolve(&mut ast);
-  }
-
-  let reduced = reduce(&ast, &symbol_table.borrow());
-  let mut state = State::new();
-  let all_output = state.evaluate(reduced, true);
-  all_output
-}
-
-macro_rules! test_in_fresh_env {
-  ($string:expr, $correct:expr) => {
-    {
-      let all_output = evaluate_all_outputs($string);
-      let ref output = all_output.last().unwrap();
-      assert_eq!(**output, Ok($correct.to_string()));
-    }
-  }
-}
-
-#[test]
-fn test_basic_eval() {
-  test_in_fresh_env!("1 + 2", "3");
-  test_in_fresh_env!("let mut a = 1; a = 2", "Unit");
-  /*
-     test_in_fresh_env!("let mut a = 1; a = 2; a", "2");
-     test_in_fresh_env!(r#"("a", 1 + 2)"#, r#"("a", 3)"#);
-     */
-}
-
-#[test]
-fn op_eval() {
-  test_in_fresh_env!("- 13", "-13");
-  test_in_fresh_env!("10 - 2", "8");
-}
-
-#[test]
-fn function_eval() {
-  test_in_fresh_env!("fn oi(x) { x + 1 }; oi(4)", "5");
-  test_in_fresh_env!("fn oi(x) { x + 1 }; oi(1+2)", "4");
-}
-
-#[test]
-fn scopes() {
-  let scope_ok = r#"
-    let a = 20
-    fn haha() {
-      let a = 10
-      a
-    }
-    haha()
-    "#;
-    test_in_fresh_env!(scope_ok, "10");
-    let scope_ok = r#"
-    let a = 20
-    fn queque() {
-      let a = 10
-      a
-    }
-    a
-    "#;
-    test_in_fresh_env!(scope_ok, "20");
-}
-
-#[test]
-fn if_is_patterns() {
-  let source = r#"
-type Option<T> = Some(T) | None
-let x = Option::Some(9); if x is Option::Some(q) then { q } else { 0 }"#;
-  test_in_fresh_env!(source, "9");
-
-  let source = r#"
-type Option<T> = Some(T) | None
-let x = Option::None; if x is Option::Some(q) then { q } else { 0 }"#;
-  test_in_fresh_env!(source, "0");
-}
-
-#[test]
-fn full_if_matching() {
-  let source = r#"
-type Option<T> = Some(T) | None
-let a = Option::None
-if a { is Option::None then 4, is Option::Some(x) then x }
-"#;
-test_in_fresh_env!(source, "4");
-
-let source = r#"
-type Option<T> = Some(T) | None
-let a = Option::Some(99)
-if a { is Option::None then 4, is Option::Some(x) then x }
-"#;
-test_in_fresh_env!(source, "99");
-
-let source = r#"
-let a = 10
-if a { is 10 then "x", is 4 then "y" }
-"#;
-test_in_fresh_env!(source, "\"x\"");
-
-let source = r#"
-let a = 10
-if a { is 15 then "x", is 10 then "y" }
-"#;
-test_in_fresh_env!(source, "\"y\"");
-}
-
-#[test]
-fn string_pattern() {
-  let source = r#"
-let a = "foo"
-if a { is "foo" then "x", is _ then "y" }
-"#;
-test_in_fresh_env!(source, "\"x\"");
-}
-
-#[test]
-fn boolean_pattern() {
-  let source = r#"
-let a = true
-if a {
-  is true then "x",
-  is false then "y"
-}
-"#;
-test_in_fresh_env!(source, "\"x\"");
-}
-
-#[test]
-fn boolean_pattern_2() {
-  let source = r#"
-let a = false
-if a { is true then "x", is false then "y" }
-"#;
-test_in_fresh_env!(source, "\"y\"");
-}
-
-#[test]
-fn ignore_pattern() {
-  let source = r#"
-type Option<T> = Some(T) | None
-if Option::Some(10) {
-  is _ then "hella"
-}
-"#;
-test_in_fresh_env!(source, "\"hella\"");
-}
-
-#[test]
-fn tuple_pattern() {
-  let source = r#"
-if (1, 2) {
-  is (1, x) then x,
-  is _ then 99
-}
-"#;
-test_in_fresh_env!(source, 2);
-}
-
-
-#[test]
-fn tuple_pattern_2() {
-  let source = r#"
-if (1, 2) {
-  is (10, x) then x,
-  is (y, x) then x + y
-}
-"#;
-test_in_fresh_env!(source, 3);
-}
-
-#[test]
-fn tuple_pattern_3() {
-  let source = r#"
-if (1, 5) {
-  is (10, x) then x,
-  is (1, x) then x
-}
-"#;
-test_in_fresh_env!(source, 5);
-}
-
-#[test]
-fn tuple_pattern_4() {
-  let source = r#"
-if (1, 5) {
-  is (10, x) then x,
-  is (1, x) then x,
-}
-"#;
-test_in_fresh_env!(source, 5);
-}
-
-#[test]
-fn  prim_obj_pattern() {
-  let source = r#"
-type Stuff = Mulch(Nat) | Jugs(Nat, String) | Mardok
-let a = Stuff::Mulch(20)
-let b = Stuff::Jugs(1, "haha")
-let c = Stuff::Mardok
-
-let x = if a {
-  is Stuff::Mulch(20) then "x",
-  is _ then "ERR"
-}
-
-let y = if b {
-  is Stuff::Mulch(n) then "ERR",
-  is Stuff::Jugs(2, _) then "ERR",
-  is Stuff::Jugs(1, s) then s,
-  is _ then "ERR",
-}
-
-let z = if c {
-  is Stuff::Jugs(_, _) then "ERR",
-  is Stuff::Mardok then "NIGH",
-  is _ then "ERR",
-}
-
-(x, y, z)
-"#;
-test_in_fresh_env!(source, r#"("x", "haha", "NIGH")"#);
-}
-
-#[test]
-fn basic_lambda_syntax() {
-  let source = r#"
-let q = \(x, y) { x * y }
-let x = q(5,2)
-let y = \(m, n, o) { m + n + o }(1,2,3)
-(x, y)
-  "#;
-test_in_fresh_env!(source, r"(10, 6)");
-}
-
-#[test]
-fn lambda_syntax_2() {
-  let source = r#"
-fn milta() {
-  \(x) { x + 33 }
-}
-milta()(10)
-  "#;
-  test_in_fresh_env!(source, "43");
-  }
-
-#[test]
-fn import_all() {
-  let source = r#"
-type Option<T> = Some(T) | None
-import Option::*
-let x = Some(9); if x is Some(q) then { q } else { 0 }"#;
-  test_in_fresh_env!(source, "9");
-}

schala-lang/language/src/lib.rs

@@ -1,46 +0,0 @@
-#![feature(trace_macros)]
-//#![feature(unrestricted_attribute_tokens)]
-#![feature(slice_patterns, box_patterns, box_syntax)]
-
-//! `schala-lang` is where the Schala programming language is actually implemented. 
-//! It defines the `Schala` type, which contains the state for a Schala REPL, and implements
-//! `ProgrammingLanguageInterface` and the chain of compiler passes for it.
-
-extern crate itertools;
-#[macro_use]
-extern crate lazy_static;
-#[macro_use]
-extern crate maplit;
-extern crate schala_repl;
-#[macro_use]
-extern crate schala_lang_codegen;
-extern crate ena;
-extern crate derivative;
-extern crate colored;
-extern crate radix_trie;
-
-
-macro_rules! bx {
-  ($e:expr) => { Box::new($e) }
-}
-
-#[macro_use]
-mod util;
-#[macro_use]
-mod typechecking;
-mod debugging;
-
-mod tokenizing;
-mod ast;
-mod parsing;
-#[macro_use]
-mod symbol_table;
-mod scope_resolution;
-mod builtin;
-mod reduced_ast;
-mod eval;
-mod source_map;
-
-mod schala;
-
-pub use schala::Schala;

schala-lang/language/src/parsing/test.rs

@@ -1,828 +0,0 @@
-#![cfg(test)]
-use std::cell::RefCell;
-use std::rc::Rc;
-use std::str::FromStr;
-
-use super::{Parser, ParseResult, tokenize};
-use crate::ast::*;
-use super::Declaration::*;
-use super::Signature;
-use super::TypeIdentifier::*;
-use super::TypeSingletonName;
-use super::ExpressionKind::*;
-use super::Variant::*;
-use super::ForBody::*;
-
-fn make_parser(input: &str) -> Parser {
-  let source_map = crate::source_map::SourceMap::new();
-  let source_map_handle = Rc::new(RefCell::new(source_map));
-  let tokens: Vec<crate::tokenizing::Token> = tokenize(input);
-  let mut parser = super::Parser::new(source_map_handle);
-  parser.add_new_tokens(tokens);
-  parser
-}
-
-fn parse(input: &str) -> ParseResult<AST> {
-  let mut parser = make_parser(input);
-  parser.parse()
-}
-
-macro_rules! parse_test {
-  ($string:expr, $correct:expr) => {
-    assert_eq!(parse($string).unwrap(), $correct)
-  };
-}
-macro_rules! parse_test_wrap_ast {
-  ($string:expr, $correct:expr) => { parse_test!($string, AST { id: ItemIdStore::new_id(), statements: vec![$correct] }) }
-}
-macro_rules! parse_error {
-  ($string:expr) => { assert!(parse($string).is_err()) }
-}
-macro_rules! qname {
-  (  $( $component:expr),* ) => {
-    {
-    let mut components = vec![];
-    $(
-      components.push(rc!($component));
-    )*
-    QualifiedName { components, id: ItemIdStore::new_id() }
-    }
-  };
-}
-macro_rules! val {
-  ($var:expr) => { Value(QualifiedName { components: vec![Rc::new($var.to_string())], id: ItemIdStore::new_id() }) };
-}
-macro_rules! ty {
-  ($name:expr) => { Singleton(tys!($name)) }
-}
-macro_rules! tys {
-  ($name:expr) => { TypeSingletonName { name: Rc::new($name.to_string()), params: vec![] } };
-}
-
-macro_rules! decl {
-  ($expr_type:expr) => {
-    Statement { id: ItemIdStore::new_id(), kind: StatementKind::Declaration($expr_type) }
-  };
-}
-
-macro_rules! import {
-  ($import_spec:expr) => {
-    Statement { id: ItemIdStore::new_id(), kind: StatementKind::Import($import_spec) }
-  }
-}
-
-macro_rules! module {
-  ($module_spec:expr) => {
-    Statement { id: ItemIdStore::new_id(), kind: StatementKind::Module($module_spec) }
-  }
-}
-
-macro_rules! ex {
-  ($expr_type:expr) => { Expression::new(ItemIdStore::new_id(), $expr_type) };
-  ($expr_type:expr, $type_anno:expr) => { Expression::with_anno(ItemIdStore::new_id(), $expr_type, $type_anno) };
-  (s $expr_text:expr) => {
-    {
-      let mut parser = make_parser($expr_text);
-      parser.expression().unwrap()
-    }
-  };
-}
-
-macro_rules! inv {
-  ($expr_type:expr) => { InvocationArgument::Positional($expr_type) }
-}
-
-macro_rules! binexp {
-  ($op:expr, $lhs:expr, $rhs:expr) => { BinExp(BinOp::from_sigil($op), bx!(Expression::new(ItemIdStore::new_id(), $lhs).into()), bx!(Expression::new(ItemIdStore::new_id(), $rhs).into())) }
-}
-macro_rules! prefexp {
-  ($op:expr, $lhs:expr) => { PrefixExp(PrefixOp::from_str($op).unwrap(), bx!(Expression::new(ItemIdStore::new_id(), $lhs).into())) }
-}
-macro_rules! exst {
-  ($expr_type:expr) => { Statement { id: ItemIdStore::new_id(), kind: StatementKind::Expression(Expression::new(ItemIdStore::new_id(), $expr_type).into())} };
-  ($expr_type:expr, $type_anno:expr) => { Statement { id: ItemIdStore::new_id(), kind: StatementKind::Expression(Expression::with_anno(ItemIdStore::new_id(), $expr_type, $type_anno).into())} };
-  ($op:expr, $lhs:expr, $rhs:expr) => { Statement { id: ItemIdStore::new_id(), ,kind: StatementKind::Expression(ex!(binexp!($op, $lhs, $rhs)))}
-  };
-  (s $statement_text:expr) => {
-    {
-      let mut parser = make_parser($statement_text);
-      parser.statement().unwrap()
-    }
-  }
-}
-
-#[test]
-fn parsing_number_literals_and_binexps() {
-  parse_test_wrap_ast! { ".2", exst!(FloatLiteral(0.2)) };
-  parse_test_wrap_ast! { "8.1", exst!(FloatLiteral(8.1)) };
-
-  parse_test_wrap_ast! { "0b010", exst!(NatLiteral(2)) };
-  parse_test_wrap_ast! { "0b0_1_0_", exst!(NatLiteral(2)) }
-
-  parse_test_wrap_ast! {"0xff", exst!(NatLiteral(255)) };
-  parse_test_wrap_ast! {"0xf_f_", exst!(NatLiteral(255)) };
-
-  parse_test_wrap_ast! {"0xf_f_+1", exst!(binexp!("+", NatLiteral(255), NatLiteral(1))) };
-
-  parse_test! {"3; 4; 4.3",
-    AST {
-      id: ItemIdStore::new_id(),
-      statements: vec![exst!(NatLiteral(3)), exst!(NatLiteral(4)),
-      exst!(FloatLiteral(4.3))]
-    }
-  };
-
-  parse_test_wrap_ast!("1 + 2 * 3",
-    exst!(binexp!("+", NatLiteral(1), binexp!("*", NatLiteral(2), NatLiteral(3))))
-  );
-
-  parse_test_wrap_ast!("1 * 2 + 3",
-    exst!(binexp!("+", binexp!("*", NatLiteral(1), NatLiteral(2)), NatLiteral(3)))
-    ) ;
-
-  parse_test_wrap_ast!("1 && 2", exst!(binexp!("&&", NatLiteral(1), NatLiteral(2))));
-
-  parse_test_wrap_ast!("1 + 2 * 3 + 4", exst!(
-    binexp!("+",
-      binexp!("+", NatLiteral(1), binexp!("*", NatLiteral(2), NatLiteral(3))),
-      NatLiteral(4))));
-
-  parse_test_wrap_ast!("(1 + 2) * 3",
-    exst!(binexp!("*", binexp!("+", NatLiteral(1), NatLiteral(2)), NatLiteral(3))));
-
-  parse_test_wrap_ast!(".1 + .2", exst!(binexp!("+", FloatLiteral(0.1), FloatLiteral(0.2))));
-  parse_test_wrap_ast!("1 / 2", exst!(binexp!("/", NatLiteral(1), NatLiteral(2))));
-}
-
-#[test]
-fn parsing_tuples() {
-  parse_test_wrap_ast!("()", exst!(TupleLiteral(vec![])));
-  parse_test_wrap_ast!("(\"hella\", 34)", exst!(
-    TupleLiteral(
-      vec![ex!(s r#""hella""#).into(), ex!(s "34").into()]
-    )
-  ));
-  parse_test_wrap_ast!("((1+2), \"slough\")", exst!(TupleLiteral(vec![
-    ex!(binexp!("+", NatLiteral(1), NatLiteral(2))).into(),
-    ex!(StringLiteral(rc!(slough))).into(),
-  ])))
-}
-
-#[test]
-fn parsing_identifiers() {
-  parse_test_wrap_ast!("a", exst!(val!("a")));
-  parse_test_wrap_ast!("some_value", exst!(val!("some_value")));
-  parse_test_wrap_ast!("a + b", exst!(binexp!("+", val!("a"), val!("b"))));
-  //parse_test!("a[b]", AST(vec![Expression(
-  //parse_test!("a[]", <- TODO THIS NEEDS TO FAIL
-  //parse_test("a()[b]()[d]")
-  //TODO fix this parsing stuff
-  /*
-  parse_test! { "perspicacity()[a]", AST(vec![
-    exst!(Index {
-      indexee: bx!(ex!(Call { f: bx!(ex!(val!("perspicacity"))), arguments: vec![] })),
-      indexers: vec![ex!(val!("a"))]
-    })
-  ])
-  }
-  */
-  parse_test_wrap_ast!("a[b,c]", exst!(Index { indexee: bx!(ex!(val!("a"))), indexers: vec![ex!(val!("b")), ex!(val!("c"))]} ));
-
-  parse_test_wrap_ast!("None", exst!(val!("None")));
-  parse_test_wrap_ast!("Pandas {  a: x + y }",
-    exst!(NamedStruct { name: qname!(Pandas), fields: vec![(rc!(a), ex!(binexp!("+", val!("x"), val!("y"))))]})
-  );
-  parse_test_wrap_ast! { "Pandas { a: n, b: q, }",
-    exst!(NamedStruct { name: qname!(Pandas), fields:
-    vec![(rc!(a), ex!(val!("n"))), (rc!(b), ex!(val!("q")))]
-    }
-    )
-  };
-}
-
-
-#[test]
-fn qualified_identifiers() {
-  parse_test_wrap_ast! {
-    "let q_q = Yolo::Swaggins",
-    decl!(Binding { name: rc!(q_q), constant: true, type_anno: None,
-    expr: Expression::new(ItemIdStore::new_id(), Value(qname!(Yolo, Swaggins))),
-    })
-  }
-
-  parse_test_wrap_ast! {
-    "thing::item::call()",
-    exst!(Call { f: bx![ex!(Value(qname!(thing, item, call)))], arguments: vec![] })
-  }
-}
-
-#[test]
-fn reserved_words() {
-  parse_error!("module::item::call()");
-}
-
-#[test]
-fn parsing_complicated_operators() {
-  parse_test_wrap_ast!("a <- b", exst!(binexp!("<-", val!("a"), val!("b"))));
-  parse_test_wrap_ast!("a || b", exst!(binexp!("||", val!("a"), val!("b"))));
-  parse_test_wrap_ast!("a<>b", exst!(binexp!("<>", val!("a"), val!("b"))));
-  parse_test_wrap_ast!("a.b.c.d", exst!(binexp!(".",
-                                              binexp!(".",
-                                                binexp!(".", val!("a"), val!("b")),
-                                              val!("c")),
-                                              val!("d"))));
-  parse_test_wrap_ast!("-3", exst!(prefexp!("-", NatLiteral(3))));
-  parse_test_wrap_ast!("-0.2", exst!(prefexp!("-", FloatLiteral(0.2))));
-  parse_test_wrap_ast!("!3", exst!(prefexp!("!", NatLiteral(3))));
-  parse_test_wrap_ast!("a <- -b", exst!(binexp!("<-", val!("a"), prefexp!("-", val!("b")))));
-  parse_test_wrap_ast!("a <--b", exst!(binexp!("<--", val!("a"), val!("b"))));
-}
-
-#[test]
-fn parsing_functions() {
-  parse_test_wrap_ast!("fn oi()",  decl!(FuncSig(Signature { name: rc!(oi), operator: false, params: vec![], type_anno: None })));
-  parse_test_wrap_ast!("oi()", exst!(Call { f: bx!(ex!(val!("oi"))), arguments: vec![] }));
-  parse_test_wrap_ast!("oi(a, 2 + 2)", exst!(Call
-  { f: bx!(ex!(val!("oi"))),
-    arguments: vec![inv!(ex!(val!("a"))), inv!(ex!(binexp!("+", NatLiteral(2), NatLiteral(2)))).into()]
-  }));
-  parse_error!("a(b,,c)");
-
-  parse_test_wrap_ast!("fn a(b, c: Int): Int", decl!(
-      FuncSig(Signature { name: rc!(a), operator: false, params: vec![
-        FormalParam { name: rc!(b), anno: None, default: None },
-        FormalParam { name: rc!(c), anno: Some(ty!("Int")), default: None }
-      ], type_anno: Some(ty!("Int")) })));
-
-
-  parse_test_wrap_ast!("fn a(x) { x() }", decl!(
-      FuncDecl(Signature { name: rc!(a), operator: false, params: vec![FormalParam { name: rc!(x), anno: None, default: None }], type_anno: None },
-      vec![exst!(Call { f: bx!(ex!(val!("x"))), arguments: vec![] })])));
-  parse_test_wrap_ast!("fn a(x) {\n x() }", decl!(
-      FuncDecl(Signature { name: rc!(a), operator: false, params: vec![FormalParam { name: rc!(x), anno: None, default: None }], type_anno: None },
-      vec![exst!(Call { f: bx!(ex!(val!("x"))), arguments: vec![] })])));
-
-  let multiline = r#"
-fn a(x) {
-x()
-}
-"#;
-parse_test_wrap_ast!(multiline, decl!(
-    FuncDecl(Signature { name: rc!(a), operator: false, params: vec![FormalParam { name: rc!(x), default: None, anno: None }], type_anno: None },
-    vec![exst!(Call { f: bx!(ex!(val!("x"))), arguments: vec![] })])));
-  let multiline2 = r#"
-fn a(x) {
-
-x()
-
-}
-"#;
-parse_test_wrap_ast!(multiline2, decl!(
-    FuncDecl(Signature { name: rc!(a), operator: false, params: vec![FormalParam { name: rc!(x), default: None, anno: None }], type_anno: None },
-    vec![exst!(s "x()")])));
-}
-
-#[test]
-fn functions_with_default_args() {
-  parse_test_wrap_ast! {
-    "fn func(x: Int, y: Int = 4) { }",
-    decl!(
-      FuncDecl(Signature { name: rc!(func), operator: false, type_anno: None, params: vec![
-        FormalParam { name: rc!(x), default: None, anno: Some(ty!("Int")) },
-        FormalParam { name: rc!(y), default: Some(ex!(s "4")), anno: Some(ty!("Int")) }
-      ]}, vec![])
-    )
-  };
-}
-
-#[test]
-fn parsing_bools() {
-  parse_test_wrap_ast!("false", exst!(BoolLiteral(false)));
-  parse_test_wrap_ast!("true", exst!(BoolLiteral(true)));
-}
-
-#[test]
-fn parsing_strings() {
-  parse_test_wrap_ast!(r#""hello""#, exst!(StringLiteral(rc!(hello))));
-}
-
-#[test]
-fn parsing_types() {
-  parse_test_wrap_ast!("type Yolo = Yolo", decl!(TypeDecl { name: tys!("Yolo"), body: TypeBody(vec![UnitStruct(rc!(Yolo))]), mutable: false} ));
-  parse_test_wrap_ast!("type mut Yolo = Yolo", decl!(TypeDecl { name: tys!("Yolo"), body: TypeBody(vec![UnitStruct(rc!(Yolo))]), mutable: true} ));
-  parse_test_wrap_ast!("type alias Sex = Drugs", decl!(TypeAlias { alias: rc!(Sex), original: rc!(Drugs) }));
-  parse_test_wrap_ast!("type Sanchez = Miguel | Alejandro(Int, Option<a>) | Esperanza { a: Int, b: String }",
-  decl!(TypeDecl {
-    name: tys!("Sanchez"),
-    body: TypeBody(vec![
-      UnitStruct(rc!(Miguel)),
-      TupleStruct(rc!(Alejandro), vec![
-        Singleton(TypeSingletonName { name: rc!(Int), params: vec![] }),
-        Singleton(TypeSingletonName { name: rc!(Option), params: vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })] }),
-      ]),
-      Record{
-        name: rc!(Esperanza),
-        members: vec![
-          (rc!(a), Singleton(TypeSingletonName { name: rc!(Int), params: vec![] })),
-          (rc!(b), Singleton(TypeSingletonName { name: rc!(String), params: vec![] })),
-        ]
-      }
-    ]),
-    mutable: false
-  }));
-
-  parse_test_wrap_ast! {
-    "type Jorge<a> = Diego | Kike(a)",
-    decl!(TypeDecl{
-      name: TypeSingletonName { name: rc!(Jorge), params: vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })] },
-      body: TypeBody(vec![UnitStruct(rc!(Diego)), TupleStruct(rc!(Kike), vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })])]),
-      mutable: false
-    }
-    )
-  };
-}
-
-#[test]
-fn parsing_bindings() {
-  parse_test_wrap_ast!("let mut a = 10", decl!(Binding { name: rc!(a), constant: false, type_anno: None, expr: ex!(NatLiteral(10)) } ));
-  parse_test_wrap_ast!("let a = 2 + 2", decl!(Binding { name: rc!(a), constant: true, type_anno: None, expr: ex!(binexp!("+", NatLiteral(2), NatLiteral(2))) }));
-  parse_test_wrap_ast!("let a: Nat = 2 + 2", decl!(
-      Binding { name: rc!(a), constant: true, type_anno: Some(Singleton(TypeSingletonName { name: rc!(Nat), params: vec![] })),
-      expr: ex!(binexp!("+", NatLiteral(2), NatLiteral(2))) }
-  ));
-}
-
-#[test]
-fn parsing_block_expressions() {
-  parse_test_wrap_ast! {
-    "if a() then { b(); c() }", exst!(
-      IfExpression {
-        discriminator: Some(bx! {
-          ex!(Call { f: bx!(ex!(val!("a"))), arguments: vec![]})
-        }),
-        body: bx! {
-          IfExpressionBody::SimpleConditional {
-            then_case: vec![exst!(Call { f: bx!(ex!(val!("b"))), arguments: vec![]}), exst!(Call { f: bx!(ex!(val!("c"))), arguments: vec![] })],
-            else_case: None,
-          }
-        }
-      }
-    )
-  };
-
-  parse_test_wrap_ast! {
-    "if a() then { b(); c() } else { q }", exst!(
-      IfExpression {
-        discriminator: Some(bx! {
-          ex!(Call { f: bx!(ex!(val!("a"))), arguments: vec![]})
-        }),
-        body: bx! {
-          IfExpressionBody::SimpleConditional {
-            then_case: vec![exst!(Call { f: bx!(ex!(val!("b"))), arguments: vec![]}), exst!(Call { f: bx!(ex!(val!("c"))), arguments: vec![] })],
-            else_case: Some(vec![exst!(val!("q"))]),
-          }
-        }
-      }
-    )
-  };
-
-  /*
-  parse_test!("if a() then { b(); c() }", AST(vec![exst!(
-      IfExpression(bx!(ex!(Call { f: bx!(ex!(val!("a"))), arguments: vec![]})),
-        vec![exst!(Call { f: bx!(ex!(val!("b"))), arguments: vec![]}), exst!(Call { f: bx!(ex!(val!("c"))), arguments: vec![] })],
-        None)
-      )]));
-  parse_test!(r#"
-  if true then {
-    const a = 10
-    b
-  } else {
-    c
-  }"#,
-  AST(vec![exst!(IfExpression(bx!(ex!(BoolLiteral(true))),
-    vec![decl!(Binding { name: rc!(a), constant: true, expr: ex!(NatLiteral(10)) }),
-          exst!(val!(rc!(b)))],
-    Some(vec![exst!(val!(rc!(c)))])))])
-  );
-
-  parse_test!("if a { b } else { c }", AST(vec![exst!(
-        IfExpression(bx!(ex!(val!("a"))),
-          vec![exst!(val!("b"))],
-          Some(vec![exst!(val!("c"))])))]));
-
-  parse_test!("if (A {a: 1}) { b } else { c }", AST(vec![exst!(
-        IfExpression(bx!(ex!(NamedStruct { name: rc!(A), fields: vec![(rc!(a), ex!(NatLiteral(1)))]})),
-          vec![exst!(val!("b"))],
-          Some(vec![exst!(val!("c"))])))]));
-
-  parse_error!("if A {a: 1} { b } else { c }");
-  */
-}
-#[test]
-fn parsing_interfaces() {
-  parse_test_wrap_ast!("interface Unglueable { fn unglue(a: Glue); fn mar(): Glue }",
-  decl!(Interface {
-    name: rc!(Unglueable),
-    signatures: vec![
-      Signature {
-        name: rc!(unglue),
-        operator: false,
-        params: vec![
-          FormalParam { name: rc!(a), anno: Some(Singleton(TypeSingletonName { name: rc!(Glue), params: vec![] })), default: None }
-        ],
-        type_anno: None
-      },
-      Signature { name: rc!(mar), operator: false, params: vec![], type_anno: Some(Singleton(TypeSingletonName { name: rc!(Glue), params: vec![] })) },
-    ]
-  })
-  );
-}
-
-#[test]
-fn parsing_impls() {
-  parse_test_wrap_ast!("impl Heh { fn yolo(); fn swagg(); }",
-  decl!(Impl {
-    type_name: ty!("Heh"),
-    interface_name: None,
-    block: vec![
-      FuncSig(Signature { name: rc!(yolo), operator: false, params: vec![], type_anno: None }),
-      FuncSig(Signature { name: rc!(swagg), operator: false, params: vec![], type_anno: None })
-    ] }));
-
-  parse_test_wrap_ast!("impl Mondai for Lollerino { fn yolo(); fn swagg(); }",
-  decl!(Impl {
-    type_name: ty!("Lollerino"),
-    interface_name: Some(TypeSingletonName { name: rc!(Mondai), params: vec![] }),
-    block: vec![
-      FuncSig(Signature { name: rc!(yolo), operator: false, params: vec![], type_anno: None}),
-      FuncSig(Signature { name: rc!(swagg), operator: false, params: vec![], type_anno: None })
-    ] }));
-
-  parse_test_wrap_ast!("impl Hella<T> for (Alpha, Omega) { }",
-  decl!(Impl {
-    type_name: Tuple(vec![ty!("Alpha"), ty!("Omega")]),
-    interface_name: Some(TypeSingletonName { name: rc!(Hella), params: vec![ty!("T")] }),
-    block: vec![]
-  })
-  );
-
-  parse_test_wrap_ast!("impl Option<WTFMate> { fn oi() }",
-  decl!(Impl {
-    type_name: Singleton(TypeSingletonName { name: rc!(Option), params: vec![ty!("WTFMate")]}),
-    interface_name: None,
-    block: vec![
-      FuncSig(Signature { name: rc!(oi), operator: false, params: vec![], type_anno: None }),
-    ]
-  }));
-}
-
-#[test]
-fn parsing_type_annotations() {
-  parse_test_wrap_ast!("let a = b : Int",
-    decl!(Binding { name: rc!(a), constant: true, type_anno: None, expr:
-      ex!(val!("b"), ty!("Int")) }));
-
-  parse_test_wrap_ast!("a : Int",
-    exst!(val!("a"), ty!("Int"))
-  );
-
-  parse_test_wrap_ast!("a : Option<Int>",
-    exst!(val!("a"), Singleton(TypeSingletonName { name: rc!(Option), params: vec![ty!("Int")] }))
-  );
-
-  parse_test_wrap_ast!("a : KoreanBBQSpecifier<Kimchi, Option<Bulgogi> >",
-    exst!(val!("a"), Singleton(TypeSingletonName { name: rc!(KoreanBBQSpecifier), params: vec![
-      ty!("Kimchi"), Singleton(TypeSingletonName { name: rc!(Option), params: vec![ty!("Bulgogi")] })
-    ] }))
-  );
-
-  parse_test_wrap_ast!("a : (Int, Yolo<a>)",
-    exst!(val!("a"), Tuple(
-      vec![ty!("Int"), Singleton(TypeSingletonName {
-        name: rc!(Yolo), params: vec![ty!("a")]
-      })])));
-}
-
-#[test]
-fn parsing_lambdas() {
-  parse_test_wrap_ast! { r#"\(x) { x + 1}"#, exst!(
-      Lambda { params: vec![FormalParam { name: rc!(x), anno: None, default: None } ], type_anno: None, body: vec![exst!(s "x + 1")] }
-    )
-  }
-
-  parse_test_wrap_ast!(r#"\  (x: Int, y) { a;b;c;}"#,
-    exst!(Lambda {
-      params: vec![
-        FormalParam { name: rc!(x), anno: Some(ty!("Int")), default: None },
-        FormalParam { name: rc!(y), anno: None, default: None }
-      ],
-      type_anno: None,
-      body: vec![exst!(s "a"), exst!(s "b"), exst!(s "c")]
-    })
-  );
-
-  parse_test_wrap_ast! { r#"\(x){y}(1)"#,
-    exst!(Call { f: bx!(ex!(
-      Lambda {
-        params: vec![
-          FormalParam { name: rc!(x), anno: None, default: None }
-        ],
-        type_anno: None,
-        body: vec![exst!(s "y")] }
-      )),
-      arguments: vec![inv!(ex!(NatLiteral(1))).into()] })
-  };
-
-  parse_test_wrap_ast! {
-    r#"\(x: Int): String { "q" }"#,
-    exst!(Lambda {
-      params: vec![
-        FormalParam { name: rc!(x), anno: Some(ty!("Int")), default: None },
-      ],
-      type_anno: Some(ty!("String")),
-      body: vec![exst!(s r#""q""#)]
-    })
-  }
-}
-
-#[test]
-fn single_param_lambda() {
-  parse_test_wrap_ast! {
-    r"\x { x + 10 }",
-    exst!(Lambda {
-      params: vec![FormalParam { name: rc!(x), anno: None, default: None }],
-      type_anno: None,
-      body: vec![exst!(s r"x + 10")]
-    })
-  }
-
-  parse_test_wrap_ast! {
-    r"\x: Nat { x + 10 }",
-    exst!(Lambda {
-      params: vec![FormalParam { name: rc!(x), anno: Some(ty!("Nat")), default: None }],
-      type_anno: None,
-      body: vec![exst!(s r"x + 10")]
-    })
-  }
-}
-
-#[test]
-fn more_advanced_lambdas() {
-  parse_test! {
-    r#"fn wahoo() { let a = 10; \(x) { x + a } };
-    wahoo()(3) "#,
-    AST {
-      id: ItemIdStore::new_id(),
-      statements: vec![
-        exst!(s r"fn wahoo() { let a = 10; \(x) { x + a } }"),
-        exst! {
-        Call {
-          f: bx!(ex!(Call { f: bx!(ex!(val!("wahoo"))), arguments: vec![] })),
-          arguments: vec![inv!(ex!(NatLiteral(3))).into()],
-        }
-      }
-    ]
-  }
-  }
-}
-
-#[test]
-  fn list_literals() {
-    parse_test_wrap_ast! {
-      "[1,2]",
-        exst!(ListLiteral(vec![ex!(NatLiteral(1)), ex!(NatLiteral(2))]))
-    };
-  }
-
-#[test]
-fn while_expr() {
-  parse_test_wrap_ast! {
-    "while { }",
-    exst!(WhileExpression { condition: None, body: vec![] })
-  }
-
-  parse_test_wrap_ast! {
-    "while a == b { }",
-    exst!(WhileExpression { condition: Some(bx![ex![binexp!("==", val!("a"), val!("b"))]]), body: vec![] })
-  }
-}
-
-#[test]
-fn for_expr() {
-  parse_test_wrap_ast! {
-    "for { a <- maybeValue } return 1",
-    exst!(ForExpression {
-      enumerators: vec![Enumerator { id: rc!(a), generator: ex!(val!("maybeValue")) }],
-      body: bx!(MonadicReturn(ex!(s "1")))
-    })
-  }
-
-  parse_test_wrap_ast! {
-    "for n <- someRange { f(n); }",
-    exst!(ForExpression { enumerators: vec![Enumerator { id: rc!(n), generator: ex!(val!("someRange"))}],
-      body: bx!(ForBody::StatementBlock(vec![exst!(s "f(n)")]))
-    })
-  }
-}
-
-#[test]
-fn patterns() {
-  parse_test_wrap_ast! {
-    "if x is Some(a) then { 4 } else { 9 }", exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-          pattern: Pattern::TupleStruct(qname!(Some), vec![Pattern::VarOrName(qname!(a))]),
-          then_case: vec![exst!(s "4")],
-          else_case: Some(vec![exst!(s "9")]) })
-        }
-      )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is Some(a) then 4 else 9", exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-            pattern: Pattern::TupleStruct(qname!(Some), vec![Pattern::VarOrName(qname!(a))]),
-            then_case: vec![exst!(s "4")],
-            else_case: Some(vec![exst!(s "9")]) }
-          )
-        }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is Something { a, b: x } then { 4 } else { 9 }", exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-          pattern: Pattern::Record(qname!(Something), vec![
-                (rc!(a),Pattern::Literal(PatternLiteral::StringPattern(rc!(a)))),
-                (rc!(b),Pattern::VarOrName(qname!(x)))
-            ]),
-          then_case: vec![exst!(s "4")],
-          else_case: Some(vec![exst!(s "9")])
-          }
-        )
-      }
-    )
-  }
-}
-
-#[test]
-fn pattern_literals() {
-  parse_test_wrap_ast! {
-    "if x is -1 then 1 else 2",
-    exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-            pattern: Pattern::Literal(PatternLiteral::NumPattern { neg: true, num: NatLiteral(1) }),
-            then_case: vec![exst!(NatLiteral(1))],
-            else_case: Some(vec![exst!(NatLiteral(2))]),
-        })
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is 1 then 1 else 2",
-    exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-          pattern: Pattern::Literal(PatternLiteral::NumPattern { neg: false, num: NatLiteral(1) }),
-          then_case: vec![exst!(s "1")],
-          else_case: Some(vec![exst!(s "2")]),
-        })
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is true then 1 else 2",
-    exst!(
-    IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(
-            IfExpressionBody::SimplePatternMatch {
-              pattern: Pattern::Literal(PatternLiteral::BoolPattern(true)),
-              then_case: vec![exst!(NatLiteral(1))],
-              else_case: Some(vec![exst!(NatLiteral(2))]),
-          })
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is \"gnosticism\" then 1 else 2",
-      exst!(
-        IfExpression {
-          discriminator: Some(bx!(ex!(s "x"))),
-          body: bx!(IfExpressionBody::SimplePatternMatch {
-              pattern: Pattern::Literal(PatternLiteral::StringPattern(rc!(gnosticism))),
-              then_case: vec![exst!(s "1")],
-              else_case: Some(vec![exst!(s "2")]),
-          })
-        }
-      )
-  }
-}
-
-#[test]
-fn imports() {
-  parse_test_wrap_ast! {
-    "import harbinger::draughts::Norgleheim",
-    import!(ImportSpecifier { 
-      id: ItemIdStore::new_id(),
-      path_components: vec![rc!(harbinger), rc!(draughts), rc!(Norgleheim)],
-      imported_names: ImportedNames::LastOfPath
-    })
-  }
-}
-
-#[test]
-fn imports_2() {
-  parse_test_wrap_ast! {
-    "import harbinger::draughts::{Norgleheim, Xraksenlaigar}",
-    import!(ImportSpecifier { 
-      id: ItemIdStore::new_id(),
-      path_components: vec![rc!(harbinger), rc!(draughts)],
-      imported_names: ImportedNames::List(vec![
-        rc!(Norgleheim),
-        rc!(Xraksenlaigar)
-      ])
-    })
-  }
-}
-
-#[test]
-fn imports_3() {
-  parse_test_wrap_ast! {
-    "import bespouri::{}",
-    import!(ImportSpecifier { 
-      id: ItemIdStore::new_id(),
-      path_components: vec![rc!(bespouri)],
-      imported_names: ImportedNames::List(vec![])
-    })
-  }
-}
-
-
-#[test]
-fn imports_4() {
-  parse_test_wrap_ast! {
-    "import bespouri::*",
-    import!(ImportSpecifier {
-      id: ItemIdStore::new_id(),
-      path_components: vec![rc!(bespouri)],
-      imported_names: ImportedNames::All
-    })
-  }
-}
-
-
-#[test]
-fn if_expr() {
-  parse_test_wrap_ast! {
-    "if x { is 1 then 5, else 20 }",
-    exst! {
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::CondList(
-          vec![
-            ConditionArm {
-              condition: Condition::Pattern(Pattern::Literal(PatternLiteral::NumPattern { neg: false, num: NatLiteral(1)})),
-              guard: None,
-              body: vec![exst!(s "5")],
-            },
-            ConditionArm {
-              condition: Condition::Else,
-              guard: None,
-              body: vec![exst!(s "20")],
-            },
-          ]
-        ))
-      }
-    }
-  }
-}
-
-#[test]
-fn modules() {
-  parse_test_wrap_ast! {
-r#"
-  module ephraim {
-    let a = 10
-    fn nah() { 33 }
-  }
-"#,
-module!(
-  ModuleSpecifier { name: rc!(ephraim), contents: vec![
-    decl!(Binding { name: rc!(a), constant: true, type_anno: None, expr: ex!(s "10") }),
-    decl!(FuncDecl(Signature { name: rc!(nah), operator: false, params: vec![], type_anno: None }, vec![exst!(NatLiteral(33))])),
-  ] }
-)
-  }
-}

schala-lang/language/src/prelude.schala

@@ -1,14 +0,0 @@
-let _SCHALA_VERSION = "0.1.0"
-
-type Option<T> = Some(T) | None
-type Ord = LT | EQ | GT
-
-
-fn map(input: Option<T>, func: Func): Option<T> {
-  if input {
-    is Option::Some(x) then Option::Some(func(x)),
-    is Option::None then Option::None,
-  }
-}
-
-type Complicated = Sunrise | Metal { black: bool, norwegian: bool } | Fella(String, Int)

schala-lang/language/src/reduced_ast.rs

@@ -1,544 +0,0 @@
-//! # Reduced AST
-//! The reduced AST is a minimal AST designed to be built from the full AST after all possible
-//! static checks have been done. Consequently, the AST reduction phase does very little error
-//! checking itself - any errors should ideally be caught either by an earlier phase, or are
-//! runtime errors that the evaluator should handle. That said, becuase it does do table lookups
-//! that can in principle fail [especially at the moment with most static analysis not yet complete],
-//! there is an Expr variant `ReductionError` to handle these cases.
-//!
-//! A design decision to make - should the ReducedAST types contain all information about
-//! type/layout necessary for the evaluator to work? If so, then the evaluator should not
-//! have access to the symbol table at all and ReducedAST should carry that information. If not,
-//! then ReducedAST shouldn't be duplicating information that can be queried at runtime from the
-//! symbol table. But I think the former might make sense since ultimately the bytecode will be
-//! built from the ReducedAST.
-use std::rc::Rc;
-use std::str::FromStr;
-
-use crate::ast::*;
-use crate::symbol_table::{Symbol, SymbolSpec, SymbolTable, FullyQualifiedSymbolName};
-use crate::builtin::Builtin;
-use crate::util::deref_optional_box;
-
-#[derive(Debug)]
-pub struct ReducedAST(pub Vec<Stmt>);
-
-#[derive(Debug, Clone)]
-pub enum Stmt {
-  PreBinding {
-    name: Rc<String>,
-    func: Func,
-  },
-  Binding {
-    name: Rc<String>,
-    constant: bool,
-    expr: Expr,
-  },
-  Expr(Expr),
-  Noop,
-}
-
-#[derive(Debug, Clone)]
-pub enum Expr {
-  Unit,
-  Lit(Lit),
-  Sym(Rc<String>), //a Sym is anything that can be looked up by name at runtime - i.e. a function or variable address
-  Tuple(Vec<Expr>),
-  Func(Func),
-  Constructor {
-    type_name: Rc<String>,
-    name: Rc<String>,
-    tag: usize,
-    arity: usize, // n.b. arity here is always the value from the symbol table - if it doesn't match what it's being called with, that's an eval error, eval will handle it
-  },
-  Call {
-    f: Box<Expr>,
-    args: Vec<Expr>,
-  },
-  Assign {
-    val: Box<Expr>, //TODO this probably can't be a val
-    expr: Box<Expr>,
-  },
-  Conditional {
-    cond: Box<Expr>,
-    then_clause: Vec<Stmt>,
-    else_clause: Vec<Stmt>,
-  },
-  ConditionalTargetSigilValue,
-  CaseMatch {
-    cond: Box<Expr>,
-    alternatives: Vec<Alternative>
-  },
-  UnimplementedSigilValue,
-  ReductionError(String),
-}
-
-pub type BoundVars = Vec<Option<Rc<String>>>; //remember that order matters here
-
-#[derive(Debug, Clone)]
-pub struct Alternative {
-  pub matchable: Subpattern,
-  pub item: Vec<Stmt>,
-}
-
-#[derive(Debug, Clone)]
-pub struct Subpattern {
-  pub tag: Option<usize>,
-  pub subpatterns: Vec<Option<Subpattern>>,
-  pub bound_vars: BoundVars,
-  pub guard: Option<Expr>,
-}
-
-#[derive(Debug, Clone)]
-pub enum Lit {
-  Nat(u64),
-  Int(i64),
-  Float(f64),
-  Bool(bool),
-  StringLit(Rc<String>),
-}
-
-#[derive(Debug, Clone)]
-pub enum Func {
-  BuiltIn(Builtin),
-  UserDefined {
-    name: Option<Rc<String>>,
-    params: Vec<Rc<String>>,
-    body: Vec<Stmt>,
-  }
-}
-
-pub fn reduce(ast: &AST, symbol_table: &SymbolTable) -> ReducedAST {
-  let mut reducer = Reducer { symbol_table };
-  reducer.ast(ast)
-}
-
-struct Reducer<'a> {
-  symbol_table: &'a SymbolTable
-}
-
-impl<'a> Reducer<'a> {
-  fn ast(&mut self, ast: &AST) -> ReducedAST {
-    let mut output = vec![];
-    for statement in ast.statements.iter() {
-      output.push(self.statement(statement));
-    }
-    ReducedAST(output)
-  }
-
-  fn statement(&mut self, stmt: &Statement) -> Stmt {
-    match &stmt.kind {
-      StatementKind::Expression(expr) => Stmt::Expr(self.expression(&expr)),
-      StatementKind::Declaration(decl) => self.declaration(&decl),
-      StatementKind::Import(_) => Stmt::Noop,
-      StatementKind::Module(modspec) => {
-        for statement in modspec.contents.iter() {
-          self.statement(&statement);
-        }
-        Stmt::Noop
-      }
-    }
-  }
-
-  fn block(&mut self, block: &Block) -> Vec<Stmt> {
-    block.iter().map(|stmt| self.statement(stmt)).collect()
-  }
-
-  fn invocation_argument(&mut self, invoc: &InvocationArgument) -> Expr {
-    use crate::ast::InvocationArgument::*;
-    match invoc {
-      Positional(ex) => self.expression(ex),
-      Keyword { .. } => Expr::UnimplementedSigilValue,
-      Ignored => Expr::UnimplementedSigilValue,
-    }
-  }
-
-  fn expression(&mut self, expr: &Expression) -> Expr {
-    use crate::ast::ExpressionKind::*;
-    let symbol_table = self.symbol_table;
-    let ref input = expr.kind;
-    match input {
-      NatLiteral(n) => Expr::Lit(Lit::Nat(*n)),
-      FloatLiteral(f) => Expr::Lit(Lit::Float(*f)),
-      StringLiteral(s) => Expr::Lit(Lit::StringLit(s.clone())),
-      BoolLiteral(b) => Expr::Lit(Lit::Bool(*b)),
-      BinExp(binop, lhs, rhs) => self.binop(binop, lhs, rhs),
-      PrefixExp(op, arg) => self.prefix(op, arg),
-      Value(qualified_name) => self.value(qualified_name),
-      Call { f, arguments } =>  self.reduce_call_expression(f, arguments),
-      TupleLiteral(exprs) => Expr::Tuple(exprs.iter().map(|e| self.expression(e)).collect()),
-      IfExpression { discriminator, body } => self.reduce_if_expression(deref_optional_box(discriminator), body),
-      Lambda { params, body, .. } => self.reduce_lambda(params, body),
-      NamedStruct { name, fields } => self.reduce_named_struct(name, fields),
-      Index { .. } => Expr::UnimplementedSigilValue,
-      WhileExpression { .. } => Expr::UnimplementedSigilValue,
-      ForExpression { .. } => Expr::UnimplementedSigilValue,
-      ListLiteral { .. } => Expr::UnimplementedSigilValue,
-    }
-  }
-
-  fn value(&mut self, qualified_name: &QualifiedName) -> Expr {
-    let symbol_table = self.symbol_table;
-    let ref id = qualified_name.id;
-    let ref sym_name = match symbol_table.get_fqsn_from_id(id) {
-      Some(fqsn) => fqsn,
-      None => return Expr::ReductionError(format!("FQSN lookup for Value {:?} failed", qualified_name)),
-    };
-
-    //TODO this probably needs to change
-    let FullyQualifiedSymbolName(ref v) = sym_name;
-    let name = v.last().unwrap().name.clone();
-
-    let Symbol { local_name, spec, .. } = match symbol_table.lookup_by_fqsn(&sym_name) {
-      Some(s) => s,
-      //None => return Expr::ReductionError(format!("Symbol {:?} not found", sym_name)),
-      None => return Expr::Sym(name.clone())
-    };
-
-    match spec {
-      SymbolSpec::RecordConstructor { .. } => Expr::ReductionError(format!("AST reducer doesn't expect a RecordConstructor here")),
-      SymbolSpec::DataConstructor { index, type_args, type_name } => Expr::Constructor {
-        type_name: type_name.clone(),
-        name: name.clone(),
-        tag: index.clone(),
-        arity: type_args.len(),
-      },
-      SymbolSpec::Func(_) => Expr::Sym(local_name.clone()),
-      SymbolSpec::Binding => Expr::Sym(local_name.clone()), //TODO not sure if this is right, probably needs to eventually be fqsn
-      SymbolSpec::Type { .. } => Expr::ReductionError("AST reducer doesnt expect a type here".to_string())
-    }
-  }
-
-  fn reduce_lambda(&mut self, params: &Vec<FormalParam>, body: &Block) -> Expr {
-    Expr::Func(Func::UserDefined {
-      name: None,
-      params: params.iter().map(|param| param.name.clone()).collect(),
-      body: self.block(body),
-    })
-  }
-
-  fn reduce_named_struct(&mut self, name: &QualifiedName, fields: &Vec<(Rc<String>, Expression)>) -> Expr {
-    let symbol_table = self.symbol_table;
-    let ref sym_name = match symbol_table.get_fqsn_from_id(&name.id) {
-      Some(fqsn) => fqsn,
-      None => return Expr::ReductionError(format!("FQSN lookup for name {:?} failed", name)),
-    };
-
-    let FullyQualifiedSymbolName(ref v) = sym_name;
-    let ref name = v.last().unwrap().name;
-    let (type_name, index, members_from_table) = match symbol_table.lookup_by_fqsn(&sym_name) {
-      Some(Symbol { spec: SymbolSpec::RecordConstructor { members, type_name, index },  .. }) => (type_name.clone(), index, members),
-      _ => return Expr::ReductionError("Not a record constructor".to_string()),
-    };
-    let arity = members_from_table.len();
-
-    let mut args: Vec<(Rc<String>, Expr)> = fields.iter()
-      .map(|(name, expr)| (name.clone(), self.expression(expr)))
-      .collect();
-
-    args.as_mut_slice()
-      .sort_unstable_by(|(name1, _), (name2, _)| name1.cmp(name2)); //arbitrary - sorting by alphabetical order
-
-    let args = args.into_iter().map(|(_, expr)| expr).collect();
-
-    //TODO make sure this sorting actually works
-    let f = box Expr::Constructor { type_name, name: name.clone(), tag: *index, arity, };
-    Expr::Call { f, args }
-  }
-
-  fn reduce_call_expression(&mut self, func: &Expression, arguments: &Vec<InvocationArgument>) -> Expr {
-    Expr::Call {
-      f: Box::new(self.expression(func)),
-      args: arguments.iter().map(|arg| self.invocation_argument(arg)).collect(),
-    }
-  }
-
-  fn reduce_if_expression(&mut self, discriminator: Option<&Expression>, body: &IfExpressionBody) -> Expr {
-    let symbol_table = self.symbol_table;
-    let cond = Box::new(match discriminator {
-      Some(expr) => self.expression(expr),
-      None => return Expr::ReductionError(format!("blank cond if-expr not supported")),
-    });
-
-    match body {
-      IfExpressionBody::SimpleConditional { then_case, else_case } => {
-        let then_clause = self.block(&then_case);
-        let else_clause = match else_case.as_ref() {
-          None => vec![],
-          Some(stmts) => self.block(&stmts),
-        };
-        Expr::Conditional { cond, then_clause, else_clause }
-      },
-      IfExpressionBody::SimplePatternMatch { pattern, then_case, else_case } => {
-        let then_clause = self.block(&then_case);
-        let else_clause = match else_case.as_ref() {
-          None => vec![],
-          Some(stmts) => self.block(&stmts),
-        };
-
-        let alternatives = vec![
-          pattern.to_alternative(then_clause, symbol_table),
-          Alternative {
-            matchable: Subpattern {
-              tag: None,
-              subpatterns: vec![],
-              bound_vars: vec![],
-              guard: None,
-            },
-            item: else_clause
-          },
-        ];
-
-        Expr::CaseMatch {
-          cond,
-          alternatives,
-        }
-      },
-      IfExpressionBody::CondList(ref condition_arms) => {
-        let mut alternatives = vec![];
-        for arm in condition_arms {
-          match arm.condition {
-            Condition::Expression(ref _expr) => {
-              return Expr::UnimplementedSigilValue
-            },
-            Condition::Pattern(ref p) =>  {
-              let item = self.block(&arm.body);
-              let alt = p.to_alternative(item, symbol_table);
-              alternatives.push(alt);
-            },
-            Condition::TruncatedOp(_, _) => {
-              return Expr::UnimplementedSigilValue
-            },
-            Condition::Else => {
-              return Expr::UnimplementedSigilValue
-            }
-          }
-        }
-        Expr::CaseMatch { cond, alternatives }
-      }
-    }
-  }
-
-  fn binop(&mut self, binop: &BinOp, lhs: &Box<Expression>, rhs: &Box<Expression>) -> Expr {
-    let operation = Builtin::from_str(binop.sigil()).ok();
-    match operation {
-      Some(Builtin::Assignment) => Expr::Assign {
-        val: Box::new(self.expression(&*lhs)),
-        expr: Box::new(self.expression(&*rhs)),
-      },
-      Some(op) => {
-        let f = Box::new(Expr::Func(Func::BuiltIn(op)));
-        Expr::Call { f, args: vec![self.expression(&*lhs), self.expression(&*rhs)] }
-      },
-      None => {
-        //TODO handle a user-defined operation
-        Expr::UnimplementedSigilValue
-      }
-    }
-  }
-
-  fn prefix(&mut self, prefix: &PrefixOp, arg: &Box<Expression>) -> Expr {
-    match prefix.builtin {
-      Some(op) => {
-        let f = Box::new(Expr::Func(Func::BuiltIn(op)));
-        Expr::Call { f, args: vec![self.expression(arg)] }
-      },
-      None => { //TODO need this for custom prefix ops
-        Expr::UnimplementedSigilValue
-      }
-    }
-  }
-
-  fn declaration(&mut self, declaration: &Declaration) -> Stmt {
-    use self::Declaration::*;
-    match declaration {
-      Binding {name, constant, expr, .. } => Stmt::Binding { name: name.clone(), constant: *constant, expr: self.expression(expr) },
-      FuncDecl(Signature { name, params, .. }, statements) => Stmt::PreBinding {
-        name: name.clone(),
-        func: Func::UserDefined {
-          name: Some(name.clone()),
-          params: params.iter().map(|param| param.name.clone()).collect(),
-          body: self.block(&statements),
-        }
-      },
-      TypeDecl { .. } => Stmt::Noop,
-      TypeAlias{ .. } => Stmt::Noop,
-      Interface { .. } => Stmt::Noop,
-      Impl { .. } => Stmt::Expr(Expr::UnimplementedSigilValue),
-      _ => Stmt::Expr(Expr::UnimplementedSigilValue)
-    }
-  }
-}
-
-
-
-
-
-/*                     ig var   pat
- * x is SomeBigOldEnum(_, x, Some(t))
- */
-
-fn handle_symbol(symbol: Option<&Symbol>, inner_patterns: &Vec<Pattern>, symbol_table: &SymbolTable) -> Subpattern {
-  use self::Pattern::*;
-  let tag = symbol.map(|symbol| match symbol.spec {
-    SymbolSpec::DataConstructor { index, .. } => index.clone(),
-    _ => panic!("Symbol is not a data constructor - this should've been caught in type-checking"),
-  });
-  let bound_vars = inner_patterns.iter().map(|p| match p {
-    VarOrName(qualified_name) => {
-      let fqsn = symbol_table.get_fqsn_from_id(&qualified_name.id);
-      let symbol_exists = fqsn.and_then(|fqsn| symbol_table.lookup_by_fqsn(&fqsn)).is_some();
-      if symbol_exists {
-        None
-      } else {
-        let QualifiedName { components, .. } = qualified_name;
-        if components.len() == 1 {
-          Some(components[0].clone())
-        } else {
-          panic!("Bad variable name in pattern");
-        }
-      }
-    },
-    _ => None,
-  }).collect();
-
-  let subpatterns = inner_patterns.iter().map(|p| match p {
-    Ignored => None,
-    VarOrName(_) => None,
-    Literal(other) => Some(other.to_subpattern(symbol_table)),
-    tp @ TuplePattern(_) => Some(tp.to_subpattern(symbol_table)),
-    ts @ TupleStruct(_, _) => Some(ts.to_subpattern(symbol_table)),
-    Record(..) => unimplemented!(),
-  }).collect();
-
-  let guard = None;
-  /*
-     let guard_equality_exprs: Vec<Expr> = subpatterns.iter().map(|p| match p {
-     Literal(lit) => match lit {
-     _ => unimplemented!()
-     },
-     _ => unimplemented!()
-     }).collect();
-     */
-
-  Subpattern {
-    tag,
-    subpatterns,
-    guard,
-    bound_vars,
-  }
-}
-
-impl Pattern {
-  fn to_alternative(&self, item: Vec<Stmt>, symbol_table: &SymbolTable) -> Alternative {
-    let s = self.to_subpattern(symbol_table);
-    Alternative {
-      matchable: Subpattern {
-        tag: s.tag,
-        subpatterns: s.subpatterns,
-        bound_vars: s.bound_vars,
-        guard: s.guard,
-      },
-      item
-    }
-  }
-
-  fn to_subpattern(&self, symbol_table: &SymbolTable) -> Subpattern {
-    use self::Pattern::*;
-    match self {
-      TupleStruct(QualifiedName{ components, id }, inner_patterns) => {
-        let fqsn = symbol_table.get_fqsn_from_id(&id);
-        match fqsn.and_then(|fqsn| symbol_table.lookup_by_fqsn(&fqsn)) {
-          Some(symbol) => handle_symbol(Some(symbol), inner_patterns, symbol_table),
-          None => {
-            panic!("Symbol {:?} not found", components);
-          }
-        }
-      },
-      TuplePattern(inner_patterns) => handle_symbol(None, inner_patterns, symbol_table),
-      Record(_name, _pairs) => {
-        unimplemented!()
-      },
-      Ignored => Subpattern { tag: None, subpatterns: vec![], guard: None, bound_vars: vec![] },
-      Literal(lit) => lit.to_subpattern(symbol_table),
-      VarOrName(QualifiedName { components, id  }) => {
-        // if fqsn is Some, treat this as a symbol pattern. If it's None, treat it
-        // as a variable.
-        let fqsn = symbol_table.get_fqsn_from_id(&id);
-        match fqsn.and_then(|fqsn| symbol_table.lookup_by_fqsn(&fqsn)) {
-          Some(symbol) => handle_symbol(Some(symbol), &vec![], symbol_table),
-          None => {
-            let name = if components.len() == 1 {
-              components[0].clone()
-            } else {
-              panic!("check this line of code yo");
-            };
-            Subpattern {
-              tag: None,
-              subpatterns: vec![],
-              guard: None,
-              bound_vars: vec![Some(name.clone())],
-            }
-          }
-        }
-      },
-    }
-  }
-}
-
-impl PatternLiteral {
-  fn to_subpattern(&self, _symbol_table: &SymbolTable) -> Subpattern {
-    use self::PatternLiteral::*;
-    match self {
-      NumPattern { neg, num } => {
-        let comparison = Expr::Lit(match (neg, num) {
-          (false, ExpressionKind::NatLiteral(n)) => Lit::Nat(*n),
-          (false, ExpressionKind::FloatLiteral(f)) => Lit::Float(*f),
-          (true, ExpressionKind::NatLiteral(n)) => Lit::Int(-1*(*n as i64)),
-          (true, ExpressionKind::FloatLiteral(f)) => Lit::Float(-1.0*f),
-          _ => panic!("This should never happen")
-        });
-        let guard = Some(Expr::Call {
-          f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
-          args: vec![comparison, Expr::ConditionalTargetSigilValue],
-        });
-        Subpattern {
-          tag: None,
-          subpatterns: vec![],
-          guard,
-          bound_vars: vec![],
-        }
-      },
-      StringPattern(s) => {
-        let guard = Some(Expr::Call {
-          f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
-          args: vec![Expr::Lit(Lit::StringLit(s.clone())), Expr::ConditionalTargetSigilValue]
-        });
-
-        Subpattern {
-          tag: None,
-          subpatterns: vec![],
-          guard,
-          bound_vars: vec![],
-        }
-      },
-      BoolPattern(b) =>  {
-        let guard = Some(if *b {
-          Expr::ConditionalTargetSigilValue
-        } else {
-          Expr::Call {
-            f: Box::new(Expr::Func(Func::BuiltIn(Builtin::BooleanNot))),
-            args: vec![Expr::ConditionalTargetSigilValue]
-          }
-        });
-        Subpattern {
-          tag: None,
-          subpatterns: vec![],
-          guard,
-          bound_vars: vec![],
-        }
-      },
-    }
-  }
-
-}

schala-lang/language/src/schala.rs

@@ -1,338 +0,0 @@
-use stopwatch::Stopwatch;
-
-use std::time::Duration;
-use std::cell::RefCell;
-use std::rc::Rc;
-use std::collections::HashSet;
-
-use itertools::Itertools;
-use schala_repl::{ProgrammingLanguageInterface,
-ComputationRequest, ComputationResponse,
-LangMetaRequest, LangMetaResponse, GlobalOutputStats,
-DebugResponse, DebugAsk};
-use crate::{ast, reduced_ast, tokenizing, parsing, eval, typechecking, symbol_table, source_map};
-
-pub type SymbolTableHandle = Rc<RefCell<symbol_table::SymbolTable>>;
-pub type SourceMapHandle = Rc<RefCell<source_map::SourceMap>>;
-
-/// All the state necessary to parse and execute a Schala program are stored in this struct.
-/// `state` represents the execution state for the AST-walking interpreter, the other fields
-/// should be self-explanatory.
-pub struct Schala {
-  source_reference: SourceReference,
-  source_map: SourceMapHandle,
-  state: eval::State<'static>,
-  symbol_table: SymbolTableHandle,
-  resolver: crate::scope_resolution::ScopeResolver<'static>,
-  type_context: typechecking::TypeContext<'static>,
-  active_parser: parsing::Parser,
-}
-
-impl Schala {
-  fn handle_docs(&self, source: String) -> LangMetaResponse {
-    LangMetaResponse::Docs {
-      doc_string: format!("Schala item `{}` : <<Schala-lang documentation not yet implemented>>", source)
-    }
-  }
-}
-
-impl Schala {
-  /// Creates a new Schala environment *without* any prelude.
-  fn new_blank_env() -> Schala {
-    let source_map = Rc::new(RefCell::new(source_map::SourceMap::new()));
-    let symbols = Rc::new(RefCell::new(symbol_table::SymbolTable::new(source_map.clone())));
-    Schala {
-      //TODO maybe these can be the same structure
-      source_reference: SourceReference::new(),
-      symbol_table: symbols.clone(),
-      source_map: source_map.clone(),
-      resolver: crate::scope_resolution::ScopeResolver::new(symbols.clone()),
-      state: eval::State::new(),
-      type_context: typechecking::TypeContext::new(),
-      active_parser: parsing::Parser::new(source_map)
-    }
-  }
-
-  /// Creates a new Schala environment with the standard prelude, which is defined as ordinary
-  /// Schala code in the file `prelude.schala`
-  pub fn new() -> Schala {
-    let prelude = include_str!("prelude.schala");
-    let mut s = Schala::new_blank_env();
-
-    let request = ComputationRequest { source: prelude, debug_requests: HashSet::default() };
-    let response = s.run_computation(request);
-    if let Err(msg) = response.main_output {
-      panic!("Error in prelude, panicking: {}", msg);
-    }
-    s
-  }
-
-  fn handle_debug_immediate(&self, request: DebugAsk) -> DebugResponse {
-    use DebugAsk::*;
-    match request {
-      Timing => DebugResponse { ask: Timing, value: format!("Invalid") },
-      ByStage { stage_name, token } => match &stage_name[..] {
-        "symbol-table" => {
-          let value = self.symbol_table.borrow().debug_symbol_table();
-          DebugResponse {
-            ask: ByStage { stage_name: format!("symbol-table"), token },
-            value
-          }
-        },
-        s => {
-          DebugResponse {
-            ask: ByStage { stage_name: s.to_string(), token: None },
-            value: format!("Not-implemented")
-          }
-        }
-      }
-    }
-  }
-}
-
-fn tokenizing(input: &str, _handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<Vec<tokenizing::Token>, String> {
-  let tokens = tokenizing::tokenize(input);
-  comp.map(|comp| {
-    let token_string = tokens.iter().map(|t| t.to_string_with_metadata()).join(", ");
-    comp.add_artifact(token_string);
-  });
-
-  let errors: Vec<String> = tokens.iter().filter_map(|t| t.get_error()).collect();
-  if errors.len() == 0 {
-    Ok(tokens)
-  } else {
-    Err(format!("{:?}", errors))
-  }
-}
-
-fn parsing(input: Vec<tokenizing::Token>, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<ast::AST, String> {
-  use ParsingDebugType::*;
-
-  let ref mut parser = handle.active_parser;
-  parser.add_new_tokens(input);
-  let ast = parser.parse();
-
-  comp.map(|comp| {
-    let debug_format = comp.parsing.as_ref().unwrap_or(&CompactAST);
-    let debug_info = match debug_format {
-      CompactAST => match ast{
-        Ok(ref ast) => ast.compact_debug(),
-        Err(_) => "Error - see output".to_string(),
-      },
-      ExpandedAST => match ast{
-        Ok(ref ast) => ast.expanded_debug(),
-        Err(_) => "Error - see output".to_string(),
-      },
-      Trace => parser.format_parse_trace(),
-    };
-    comp.add_artifact(debug_info);
-  });
-  ast.map_err(|err| format_parse_error(err, &handle.source_reference))
-}
-
-fn format_parse_error(error: parsing::ParseError, source_reference: &SourceReference) -> String {
-  let line_num = error.token.location.line_num;
-  let ch = error.token.location.char_num;
-  let line_from_program = source_reference.get_line(line_num);
-  let location_pointer = format!("{}^", " ".repeat(ch));
-
-  let line_num_digits = format!("{}", line_num).chars().count();
-  let space_padding = " ".repeat(line_num_digits);
-
-  let production = match error.production_name {
-    Some(n) => format!("\n(from production \"{}\")", n),
-    None => "".to_string()
-  };
-
-  format!(r#"
-{error_msg}{production}
-{space_padding} |
-{line_num} | {}
-{space_padding} | {}
-"#, line_from_program, location_pointer, error_msg=error.msg, space_padding=space_padding, line_num=line_num, production=production
-)
-}
-
-fn symbol_table(input: ast::AST, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<ast::AST, String> {
-  let () = handle.symbol_table.borrow_mut().add_top_level_symbols(&input)?;
-  comp.map(|comp| {
-    let debug = handle.symbol_table.borrow().debug_symbol_table();
-    comp.add_artifact(debug);
-  });
-  Ok(input)
-}
-
-fn scope_resolution(mut input: ast::AST, handle: &mut Schala, _com: Option<&mut PassDebugArtifact>) -> Result<ast::AST, String> {
-  let () = handle.resolver.resolve(&mut input)?;
-  Ok(input)
-}
-
-fn typechecking(input: ast::AST, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<ast::AST, String> {
-  let result = handle.type_context.typecheck(&input);
-
-  comp.map(|comp| {
-    comp.add_artifact(match result {
-      Ok(ty) => ty.to_string(),
-      Err(err) => format!("Type error: {}", err.msg)
-    });
-  });
-
-  Ok(input)
-}
-
-fn ast_reducing(input: ast::AST, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<reduced_ast::ReducedAST, String> {
-  let ref symbol_table = handle.symbol_table.borrow();
-  let output = reduced_ast::reduce(&input, symbol_table);
-  comp.map(|comp| comp.add_artifact(format!("{:?}", output)));
-  Ok(output)
-}
-
-fn eval(input: reduced_ast::ReducedAST, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<String, String> {
-  comp.map(|comp| comp.add_artifact(handle.state.debug_print()));
-  let evaluation_outputs = handle.state.evaluate(input, true);
-  let text_output: Result<Vec<String>, String> = evaluation_outputs
-    .into_iter()
-    .collect();
-
-  let eval_output: Result<String, String> = text_output
-    .map(|v| { v.into_iter().intersperse(format!("\n")).collect() });
-  eval_output
-}
-
-/// Represents lines of source code
-struct SourceReference {
-  lines: Option<Vec<String>>
-}
-
-impl SourceReference {
-  fn new() -> SourceReference {
-    SourceReference { lines: None }
-  }
-
-  fn load_new_source(&mut self, source: &str) {
-    //TODO this is a lot of heap allocations - maybe there's a way to make it more efficient?
-    self.lines = Some(source.lines().map(|s| s.to_string()).collect()); }
-
-  fn get_line(&self, line: usize) -> String {
-    self.lines.as_ref().and_then(|x| x.get(line).map(|s| s.to_string())).unwrap_or(format!("NO LINE FOUND"))
-  }
-}
-
-enum ParsingDebugType {
-  CompactAST,
-  ExpandedAST,
-  Trace
-}
-
-#[derive(Default)]
-struct PassDebugArtifact {
-  parsing: Option<ParsingDebugType>,
-  artifacts: Vec<String>
-
-}
-impl PassDebugArtifact {
-  fn add_artifact(&mut self, artifact: String) {
-    self.artifacts.push(artifact)
-  }
-}
-
-fn stage_names() -> Vec<&'static str> {
-  vec![
-    "tokenizing",
-    "parsing",
-    "symbol-table",
-    "scope-resolution",
-    "typechecking",
-    "ast-reduction",
-    "ast-walking-evaluation"
-  ]
-}
-
-
-impl ProgrammingLanguageInterface for Schala {
-  fn get_language_name(&self) -> String { format!("Schala") }
-  fn get_source_file_suffix(&self) -> String { format!("schala") }
-
-  fn run_computation(&mut self, request: ComputationRequest) -> ComputationResponse {
-    struct PassToken<'a> {
-      schala: &'a mut Schala,
-      stage_durations: &'a mut Vec<(String, Duration)>,
-      sw: &'a Stopwatch,
-      debug_requests: &'a HashSet<DebugAsk>,
-      debug_responses: &'a mut Vec<DebugResponse>,
-    }
-
-    fn output_wrapper<Input, Output, F>(n: usize, func: F, input: Input, token: &mut PassToken) -> Result<Output, String>
-      where F: Fn(Input, &mut Schala, Option<&mut PassDebugArtifact>) -> Result<Output, String>
-    {
-      let stage_names = stage_names();
-      let cur_stage_name = stage_names[n];
-      let ask = token.debug_requests.iter().find(|ask| ask.is_for_stage(cur_stage_name));
-
-      let parsing = match ask {
-        Some(DebugAsk::ByStage { token, .. }) if cur_stage_name == "parsing" => Some(
-          token.as_ref().map(|token| match &token[..] {
-            "compact" => ParsingDebugType::CompactAST,
-            "expanded" => ParsingDebugType::ExpandedAST,
-            "trace" => ParsingDebugType::Trace,
-            _ => ParsingDebugType::CompactAST,
-          }).unwrap_or(ParsingDebugType::CompactAST)
-        ),
-        _ => None,
-      };
-
-      let mut debug_artifact = ask.map(|_| PassDebugArtifact {
-        parsing, ..Default::default()
-      });
-
-      let output = func(input, token.schala, debug_artifact.as_mut());
-
-      //TODO I think this is not counting the time since the *previous* stage
-      token.stage_durations.push((cur_stage_name.to_string(), token.sw.elapsed()));
-      if let Some(artifact) = debug_artifact {
-        for value in artifact.artifacts.into_iter() {
-          let resp = DebugResponse { ask: ask.unwrap().clone(), value };
-          token.debug_responses.push(resp);
-        }
-      }
-      output
-    }
-
-    let ComputationRequest { source, debug_requests } = request;
-    self.source_reference.load_new_source(source);
-    let sw = Stopwatch::start_new();
-    let mut stage_durations = Vec::new();
-    let mut debug_responses = Vec::new();
-    let mut tok = PassToken { schala: self, stage_durations: &mut stage_durations, sw: &sw, debug_requests: &debug_requests, debug_responses: &mut debug_responses };
-
-    let main_output: Result<String, String> = Ok(source)
-      .and_then(|source| output_wrapper(0, tokenizing, source, &mut tok))
-      .and_then(|tokens| output_wrapper(1, parsing, tokens, &mut tok))
-      .and_then(|ast| output_wrapper(2, symbol_table, ast, &mut tok))
-      .and_then(|ast| output_wrapper(3, scope_resolution, ast, &mut tok))
-      .and_then(|ast| output_wrapper(4, typechecking, ast, &mut tok))
-      .and_then(|ast| output_wrapper(5, ast_reducing, ast, &mut tok))
-      .and_then(|reduced_ast| output_wrapper(6, eval, reduced_ast, &mut tok));
-
-    let total_duration = sw.elapsed();
-    let global_output_stats = GlobalOutputStats {
-      total_duration, stage_durations
-    };
-
-    ComputationResponse {
-      main_output,
-      global_output_stats,
-      debug_responses,
-    }
-  }
-
-  fn request_meta(&mut self, request: LangMetaRequest) -> LangMetaResponse {
-    match request {
-      LangMetaRequest::StageNames => LangMetaResponse::StageNames(stage_names().iter().map(|s| s.to_string()).collect()),
-      LangMetaRequest::Docs { source } => self.handle_docs(source),
-      LangMetaRequest::ImmediateDebug(debug_request) =>
-        LangMetaResponse::ImmediateDebug(self.handle_debug_immediate(debug_request)),
-      LangMetaRequest::Custom { .. } => LangMetaResponse::Custom { kind: format!("not-implemented"), value: format!("") }
-    }
-  }
-}

schala-lang/language/src/scope_resolution.rs

@@ -1,119 +0,0 @@
-use std::rc::Rc;
-
-use crate::schala::SymbolTableHandle;
-use crate::symbol_table::{ScopeSegment, FullyQualifiedSymbolName};
-use crate::ast::*;
-use crate::util::ScopeStack;
-
-type FQSNPrefix = Vec<ScopeSegment>;
-
-pub struct ScopeResolver<'a> {
-  symbol_table_handle: SymbolTableHandle,
-  name_scope_stack: ScopeStack<'a, Rc<String>, FQSNPrefix>,
-}
-
-impl<'a> ASTVisitor for ScopeResolver<'a> {
-  //TODO need to un-insert these - maybe need to rethink visitor
-  fn import(&mut self, import_spec: &ImportSpecifier) {
-    let ref symbol_table = self.symbol_table_handle.borrow();
-    let ImportSpecifier { ref path_components, ref imported_names, .. } = &import_spec;
-    match imported_names {
-      ImportedNames::All => {
-        let prefix = FullyQualifiedSymbolName(path_components.iter().map(|c| ScopeSegment {
-          name: c.clone(),
-        }).collect());
-        let members = symbol_table.lookup_children_of_fqsn(&prefix);
-        for member in members.into_iter() {
-          let local_name = member.0.last().unwrap().name.clone();
-          self.name_scope_stack.insert(local_name.clone(), member.0);
-        }
-      },
-      ImportedNames::LastOfPath => {
-        let name = path_components.last().unwrap(); //TODO handle better
-        let fqsn_prefix = path_components.iter().map(|c| ScopeSegment {
-          name: c.clone(),
-        }).collect();
-        self.name_scope_stack.insert(name.clone(), fqsn_prefix);
-      }
-      ImportedNames::List(ref names) => {
-        let fqsn_prefix: FQSNPrefix = path_components.iter().map(|c| ScopeSegment {
-          name: c.clone(),
-        }).collect();
-        for name in names.iter() {
-          self.name_scope_stack.insert(name.clone(), fqsn_prefix.clone());
-        }
-      }
-    };
-  }
-
-  fn qualified_name(&mut self, qualified_name: &QualifiedName) {
-    let ref mut symbol_table = self.symbol_table_handle.borrow_mut();
-    let fqsn = self.lookup_name_in_scope(&qualified_name);
-    let ref id = qualified_name.id;
-    symbol_table.map_id_to_fqsn(id, fqsn);
-  }
-
-  fn named_struct(&mut self, name: &QualifiedName, _fields: &Vec<(Rc<String>, Expression)>) {
-    let ref mut symbol_table = self.symbol_table_handle.borrow_mut();
-    let ref id = name.id;
-    let fqsn = self.lookup_name_in_scope(&name);
-    symbol_table.map_id_to_fqsn(id, fqsn);
-  }
-
-  fn pattern(&mut self, pat: &Pattern) {
-    use Pattern::*;
-    match pat {
-      Ignored => (),
-      TuplePattern(_) => (),
-      Literal(_) => (),
-      TupleStruct(name, _) => self.qualified_name_in_pattern(name),
-      Record(name, _) => self.qualified_name_in_pattern(name),
-      VarOrName(name) => self.qualified_name_in_pattern(name),
-    };
-  }
-}
-
-impl<'a> ScopeResolver<'a> {
-  pub fn new(symbol_table_handle: SymbolTableHandle) -> ScopeResolver<'static> {
-    let name_scope_stack = ScopeStack::new(None);
-    ScopeResolver { symbol_table_handle, name_scope_stack }
-  }
-  pub fn resolve(&mut self, ast: &mut AST) -> Result<(), String> {
-    walk_ast(self, ast);
-    Ok(())
-  }
-
-  fn lookup_name_in_scope(&self, sym_name: &QualifiedName) -> FullyQualifiedSymbolName {
-    let QualifiedName { components, .. } = sym_name;
-    let first_component = &components[0];
-    match self.name_scope_stack.lookup(first_component) {
-      None => {
-        FullyQualifiedSymbolName(components.iter().map(|name| ScopeSegment { name: name.clone() }).collect())
-      },
-      Some(fqsn_prefix) => {
-        let mut full_name = fqsn_prefix.clone();
-        let rest_of_name: FQSNPrefix = components[1..].iter().map(|name| ScopeSegment { name: name.clone() }).collect();
-        full_name.extend_from_slice(&rest_of_name);
-        FullyQualifiedSymbolName(full_name)
-      }
-    }
-  }
-
-  /// this might be a variable or a pattern. if a variable, set to none
-  fn qualified_name_in_pattern(&mut self, qualified_name: &QualifiedName) {
-    let ref mut symbol_table = self.symbol_table_handle.borrow_mut();
-    let ref id = qualified_name.id;
-    let fqsn = self.lookup_name_in_scope(qualified_name);
-    if symbol_table.lookup_by_fqsn(&fqsn).is_some() {
-      symbol_table.map_id_to_fqsn(&id, fqsn);
-    }
-  }
-}
-
-#[cfg(test)]
-mod tests {
-  #[test]
-  fn basic_scope() {
-
-  }
-}

schala-lang/language/src/source_map.rs

@@ -1,39 +0,0 @@
-use std::collections::HashMap;
-use std::fmt;
-
-use crate::ast::ItemId;
-
-pub type LineNumber = usize;
-
-#[derive(Debug, Clone, Copy, PartialEq)]
-pub struct Location {
-  pub line_num: LineNumber,
-  pub char_num: usize,
-}
-
-impl fmt::Display for Location {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    write!(f, "{}:{}", self.line_num, self.char_num)
-  }
-}
-
-pub struct SourceMap {
-  map: HashMap<ItemId, Location>
-}
-
-impl SourceMap {
-  pub fn new() -> SourceMap {
-    SourceMap { map: HashMap::new() }
-  }
-
-  pub fn add_location(&mut self, id: &ItemId, loc: Location) {
-    self.map.insert(id.clone(), loc);
-  }
-
-  pub fn lookup(&self, id: &ItemId) -> Option<Location> {
-    match self.map.get(id) {
-      Some(loc) => Some(loc.clone()),
-      None => None
-    }
-  }
-}

schala-lang/language/src/symbol_table.rs

@@ -1,343 +0,0 @@
-use std::collections::HashMap;
-use std::collections::hash_map::Entry;
-use std::rc::Rc;
-use std::fmt;
-use std::fmt::Write;
-
-use crate::schala::SourceMapHandle;
-use crate::source_map::{SourceMap, LineNumber};
-use crate::ast;
-use crate::ast::{ItemId, TypeBody, TypeSingletonName, Signature, Statement, StatementKind, ModuleSpecifier};
-use crate::typechecking::TypeName;
-
-
-#[allow(unused_macros)]
-macro_rules! fqsn {
-  ( $( $name:expr ; $kind:tt),* ) => {
-    {
-      let mut vec = vec![];
-      $(
-        vec.push(crate::symbol_table::ScopeSegment::new(std::rc::Rc::new($name.to_string())));
-      )*
-      FullyQualifiedSymbolName(vec)
-    }
-  };
-}
-
-mod symbol_trie;
-use symbol_trie::SymbolTrie;
-mod test;
-
-/// Keeps track of what names were used in a given namespace. Call try_register to add a name to
-/// the table, or report an error if a name already exists.
-struct DuplicateNameTrackTable {
-  table: HashMap<Rc<String>, LineNumber>,
-}
-
-impl DuplicateNameTrackTable {
-  fn new() -> DuplicateNameTrackTable {
-    DuplicateNameTrackTable { table: HashMap::new() }
-  }
-
-  fn try_register(&mut self, name: &Rc<String>, id: &ItemId, source_map: &SourceMap) -> Result<(), LineNumber> {
-    match self.table.entry(name.clone()) {
-      Entry::Occupied(o) => {
-        let line_number = o.get();
-        Err(*line_number)
-      },
-      Entry::Vacant(v) => {
-        let line_number = if let Some(loc) = source_map.lookup(id) {
-          loc.line_num
-        } else {
-          0
-        };
-        v.insert(line_number);
-        Ok(())
-      }
-    }
-  }
-}
-
-#[derive(PartialEq, Eq, Hash, Debug, Clone, PartialOrd, Ord)]
-pub struct FullyQualifiedSymbolName(pub Vec<ScopeSegment>);
-
-impl fmt::Display for FullyQualifiedSymbolName {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    let FullyQualifiedSymbolName(v) = self;
-    for segment in v {
-      write!(f, "::{}", segment)?;
-    }
-    Ok(())
-  }
-}
-
-#[derive(Debug, Clone, Eq, PartialEq, Hash, PartialOrd, Ord)]
-pub struct ScopeSegment {
-  pub name: Rc<String>, //TODO maybe this could be a &str, for efficiency?
-}
-
-impl fmt::Display for ScopeSegment {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    let kind = ""; //TODO implement some kind of kind-tracking here
-    write!(f, "{}{}", self.name, kind)
-  }
-}
-
-impl ScopeSegment {
-  pub fn new(name: Rc<String>) ->  ScopeSegment {
-    ScopeSegment { name }
-  }
-}
-
-
-//cf. p. 150 or so of Language Implementation Patterns
-pub struct SymbolTable {
-  source_map_handle: SourceMapHandle,
-  symbol_path_to_symbol: HashMap<FullyQualifiedSymbolName, Symbol>,
-  id_to_fqsn: HashMap<ItemId, FullyQualifiedSymbolName>,
-  symbol_trie: SymbolTrie,
-}
-
-impl SymbolTable {
-  pub fn new(source_map_handle: SourceMapHandle) -> SymbolTable {
-    SymbolTable {
-      source_map_handle,
-      symbol_path_to_symbol: HashMap::new(),
-      id_to_fqsn: HashMap::new(),
-      symbol_trie: SymbolTrie::new()
-    }
-  }
-
-  pub fn map_id_to_fqsn(&mut self, id: &ItemId, fqsn: FullyQualifiedSymbolName) {
-    self.id_to_fqsn.insert(id.clone(), fqsn);
-  }
-
-  pub fn get_fqsn_from_id(&self, id: &ItemId) -> Option<FullyQualifiedSymbolName> {
-    self.id_to_fqsn.get(&id).cloned()
-  }
-
-  fn add_new_symbol(&mut self, local_name: &Rc<String>, scope_path: &Vec<ScopeSegment>, spec: SymbolSpec) {
-    let mut vec: Vec<ScopeSegment> = scope_path.clone();
-    vec.push(ScopeSegment { name: local_name.clone() });
-    let fully_qualified_name = FullyQualifiedSymbolName(vec);
-    let symbol = Symbol { local_name: local_name.clone(), fully_qualified_name: fully_qualified_name.clone(), spec };
-    self.symbol_trie.insert(&fully_qualified_name);
-    self.symbol_path_to_symbol.insert(fully_qualified_name, symbol);
-  }
-
-  pub fn lookup_by_fqsn(&self, fully_qualified_path: &FullyQualifiedSymbolName) -> Option<&Symbol> {
-    self.symbol_path_to_symbol.get(fully_qualified_path)
-  }
-
-  pub fn lookup_children_of_fqsn(&self, path: &FullyQualifiedSymbolName) -> Vec<FullyQualifiedSymbolName> {
-    self.symbol_trie.get_children(path)
-  }
-}
-
-#[derive(Debug)]
-pub struct Symbol {
-  pub local_name: Rc<String>, //TODO does this need to be pub?
-  fully_qualified_name: FullyQualifiedSymbolName,
-  pub spec: SymbolSpec,
-}
-
-impl fmt::Display for Symbol {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    write!(f, "<Local name: {}, Spec: {}>", self.local_name, self.spec)
-  }
-}
-
-#[derive(Debug)]
-pub enum SymbolSpec {
-  Func(Vec<TypeName>),
-  DataConstructor {
-    index: usize,
-    type_name: TypeName,
-    type_args: Vec<Rc<String>>,
-  },
-  RecordConstructor {
-    index: usize,
-    members: HashMap<Rc<String>, TypeName>,
-    type_name: TypeName,
-  },
-  Binding,
-  Type {
-    name: TypeName
-  },
-}
-
-impl fmt::Display for SymbolSpec {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    use self::SymbolSpec::*;
-    match self {
-      Func(type_names) => write!(f, "Func({:?})", type_names),
-      DataConstructor { index, type_name, type_args } => write!(f, "DataConstructor(idx: {})({:?} -> {})", index, type_args, type_name),
-      RecordConstructor { type_name, index, ..} => write!(f, "RecordConstructor(idx: {})(<members> -> {})", index, type_name),
-      Binding => write!(f, "Binding"),
-      Type { name } => write!(f, "Type <{}>", name),
-    }
-  }
-}
-
-impl SymbolTable {
-  /* note: this adds names for *forward reference* but doesn't actually create any types. solve that problem
-   * later */
-
-  pub fn add_top_level_symbols(&mut self, ast: &ast::AST) -> Result<(), String> {
-    let mut scope_name_stack = Vec::new();
-    self.add_symbols_from_scope(&ast.statements, &mut scope_name_stack)
-  }
-
-  fn add_symbols_from_scope<'a>(&'a mut self, statements: &Vec<Statement>, scope_name_stack: &mut Vec<ScopeSegment>) -> Result<(), String> {
-    use self::ast::Declaration::*;
-
-    let mut seen_identifiers = DuplicateNameTrackTable::new();
-    let mut seen_modules = DuplicateNameTrackTable::new();
-
-    for statement in statements.iter() {
-      match statement {
-        Statement { kind: StatementKind::Declaration(decl), id } => {
-          match decl {
-            FuncSig(ref signature) => {
-              seen_identifiers.try_register(&signature.name, &id, &self.source_map_handle.borrow())
-                .map_err(|line| format!("Duplicate function definition: {}. It's already defined at {}", signature.name, line))?;
-              self.add_function_signature(signature, scope_name_stack)?
-            }
-            FuncDecl(ref signature, ref body) => {
-              seen_identifiers.try_register(&signature.name, &id, &self.source_map_handle.borrow())
-                .map_err(|line| format!("Duplicate function definition: {}. It's already defined at {}", signature.name, line))?;
-              self.add_function_signature(signature, scope_name_stack)?;
-              scope_name_stack.push(ScopeSegment{
-                name: signature.name.clone(),
-              });
-              let output = self.add_symbols_from_scope(body, scope_name_stack);
-              scope_name_stack.pop();
-              output?
-            },
-            TypeDecl { name, body, mutable } => {
-              seen_identifiers.try_register(&name.name, &id, &self.source_map_handle.borrow())
-                .map_err(|line| format!("Duplicate type definition: {}. It's already defined at {}", name.name, line))?;
-              self.add_type_decl(name, body, mutable, scope_name_stack)?
-            },
-            Binding { name, .. } => {
-              seen_identifiers.try_register(&name, &id, &self.source_map_handle.borrow())
-                .map_err(|line| format!("Duplicate variable definition: {}. It's already defined at {}", name, line))?;
-              self.add_new_symbol(name, scope_name_stack, SymbolSpec::Binding);
-            }
-            _ => ()
-          }
-        },
-        Statement { kind: StatementKind::Module(ModuleSpecifier { name, contents}), id } => {
-          seen_modules.try_register(&name, &id, &self.source_map_handle.borrow())
-            .map_err(|line| format!("Duplicate module definition: {}. It's already defined at {}", name, line))?;
-          scope_name_stack.push(ScopeSegment { name: name.clone() });
-          let output = self.add_symbols_from_scope(contents, scope_name_stack);
-          scope_name_stack.pop();
-          output?
-        },
-        _ => ()
-      }
-    }
-    Ok(())
-  }
-  pub fn debug_symbol_table(&self) -> String {
-    let mut output = format!("Symbol table\n");
-    let mut sorted_symbols: Vec<(&FullyQualifiedSymbolName, &Symbol)> = self.symbol_path_to_symbol.iter().collect();
-    sorted_symbols.sort_by(|(fqsn, _), (other_fqsn, _)| fqsn.cmp(other_fqsn));
-    for (name, sym) in sorted_symbols.iter() {
-      write!(output, "{} -> {}\n", name, sym).unwrap();
-    }
-    output
-  }
-
-  fn add_function_signature(&mut self, signature: &Signature, scope_name_stack: &mut Vec<ScopeSegment>) -> Result<(), String> {
-    let mut local_type_context = LocalTypeContext::new();
-    let types = signature.params.iter().map(|param| match param.anno {
-      Some(ref type_identifier) => Rc::new(format!("{:?}", type_identifier)),
-      None => local_type_context.new_universal_type()
-    }).collect();
-    self.add_new_symbol(&signature.name, scope_name_stack, SymbolSpec::Func(types));
-    Ok(())
-  }
-
-  //TODO handle type mutability
-  fn add_type_decl(&mut self, type_name: &TypeSingletonName, body: &TypeBody, _mutable: &bool, scope_name_stack: &mut Vec<ScopeSegment>) -> Result<(), String> {
-    use crate::ast::{TypeIdentifier, Variant};
-    let TypeBody(variants) = body;
-    let ref type_name = type_name.name;
-
-
-    let type_spec = SymbolSpec::Type {
-      name: type_name.clone(),
-    };
-    self.add_new_symbol(type_name, &scope_name_stack, type_spec);
-
-    scope_name_stack.push(ScopeSegment{
-      name: type_name.clone(),
-    });
-    //TODO figure out why _params isn't being used here
-    for (index, var) in variants.iter().enumerate() {
-      match var {
-        Variant::UnitStruct(variant_name) => {
-          let spec = SymbolSpec::DataConstructor {
-            index,
-            type_name: type_name.clone(),
-            type_args: vec![],
-          };
-          self.add_new_symbol(variant_name, scope_name_stack, spec);
-        },
-        Variant::TupleStruct(variant_name, tuple_members) => {
-          //TODO fix the notion of a tuple type
-          let type_args = tuple_members.iter().map(|type_name| match type_name {
-            TypeIdentifier::Singleton(TypeSingletonName { name, ..}) => name.clone(),
-            TypeIdentifier::Tuple(_) => unimplemented!(),
-          }).collect();
-          let spec = SymbolSpec::DataConstructor {
-            index,
-            type_name: type_name.clone(),
-            type_args
-          };
-          self.add_new_symbol(variant_name, scope_name_stack, spec);
-        },
-        Variant::Record { name, members: defined_members } => {
-          let mut members = HashMap::new();
-          let mut duplicate_member_definitions = Vec::new();
-          for (member_name, member_type) in defined_members {
-            match members.entry(member_name.clone()) {
-              Entry::Occupied(_) => duplicate_member_definitions.push(member_name.clone()),
-              Entry::Vacant(v) => {
-                v.insert(match member_type {
-                  TypeIdentifier::Singleton(TypeSingletonName { name, ..}) => name.clone(),
-                  TypeIdentifier::Tuple(_) => unimplemented!(),
-                });
-              }
-            }
-          }
-          if duplicate_member_definitions.len() != 0 {
-            return Err(format!("Duplicate member(s) in definition of type {}: {:?}", type_name, duplicate_member_definitions));
-          }
-          let spec = SymbolSpec::RecordConstructor { index, type_name: type_name.clone(), members };
-          self.add_new_symbol(name, scope_name_stack, spec);
-        },
-      }
-    }
-    scope_name_stack.pop();
-    Ok(())
-  }
-}
-
-struct LocalTypeContext {
-  state: u8
-}
-impl LocalTypeContext {
-  fn new() -> LocalTypeContext {
-    LocalTypeContext { state: 0 }
-  }
-
-  fn new_universal_type(&mut self) -> TypeName {
-    let n = self.state;
-    self.state += 1;
-    Rc::new(format!("{}", (('a' as u8) + n) as char))
-  }
-}
-

schala-lang/language/src/symbol_table/symbol_trie.rs

@@ -1,51 +0,0 @@
-use radix_trie::{Trie, TrieCommon, TrieKey};
-use super::FullyQualifiedSymbolName;
-use std::hash::{Hasher, Hash};
-use std::collections::hash_map::DefaultHasher;
-
-#[derive(Debug)]
-pub struct SymbolTrie(Trie<FullyQualifiedSymbolName, ()>);
-
-impl TrieKey for FullyQualifiedSymbolName {
-  fn encode_bytes(&self) -> Vec<u8> {
-    let mut hasher = DefaultHasher::new();
-    let mut output = vec![];
-    let FullyQualifiedSymbolName(scopes) = self;
-    for segment in scopes.iter() {
-      segment.name.as_bytes().hash(&mut hasher);
-      output.extend_from_slice(&hasher.finish().to_be_bytes());
-    }
-    output
-  }
-}
-
-impl SymbolTrie {
-  pub fn new() -> SymbolTrie {
-    SymbolTrie(Trie::new())
-  }
-
-  pub fn insert(&mut self, fqsn: &FullyQualifiedSymbolName) {
-    self.0.insert(fqsn.clone(), ());
-  }
-
-  pub fn get_children(&self, fqsn: &FullyQualifiedSymbolName) -> Vec<FullyQualifiedSymbolName> {
-    let subtrie = match self.0.subtrie(fqsn) {
-      Some(s) => s,
-      None => return vec![]
-    };
-    let output: Vec<FullyQualifiedSymbolName> = subtrie.keys().filter(|cur_key| **cur_key != *fqsn).map(|fqsn| fqsn.clone()).collect();
-    output
-  }
-}
-
-#[test]
-fn test_trie_insertion() {
-  let mut trie = SymbolTrie::new();
-
-  trie.insert(&fqsn!("unrelated"; ty, "thing"; tr));
-  trie.insert(&fqsn!("outer"; ty, "inner"; tr));
-  trie.insert(&fqsn!("outer"; ty, "inner"; ty, "still_inner"; tr));
-
-  let children = trie.get_children(&fqsn!("outer"; ty, "inner"; tr));
-  assert_eq!(children.len(), 1);
-}

schala-lang/language/src/symbol_table/test.rs

@@ -1,193 +0,0 @@
-#![cfg(test)]
-use std::cell::RefCell;
-use std::rc::Rc;
-
-use super::*;
-use crate::util::quick_ast;
-
-fn add_symbols_from_source(src: &str) -> (SymbolTable, Result<(), String>) {
-  let (ast, source_map) = quick_ast(src);
-  let source_map = Rc::new(RefCell::new(source_map));
-  let mut symbol_table = SymbolTable::new(source_map);
-  let result = symbol_table.add_top_level_symbols(&ast);
-  (symbol_table, result)
-}
-
-macro_rules! values_in_table {
-  ($source:expr, $single_value:expr) => {
-    values_in_table!($source => $single_value);
-  };
-  ($source:expr => $( $value:expr ),* ) => {
-    {
-    let (symbol_table, _) = add_symbols_from_source($source);
-    $(
-      match symbol_table.lookup_by_fqsn($value) {
-        Some(_spec) => (),
-        None => panic!(),
-      };
-    )*
-    }
-  };
-}
-
-#[test]
-fn basic_symbol_table() {
-  values_in_table! { "let a = 10; fn b() { 20 }", &fqsn!("b"; tr) };
-  values_in_table! { "type Option<T> = Some(T) | None" =>
-    &fqsn!("Option"; tr),
-    &fqsn!("Option"; ty, "Some"; tr),
-    &fqsn!("Option"; ty, "None"; tr) };
-}
-
-#[test]
-fn no_function_definition_duplicates() {
-  let source = r#"
-  fn a() { 1 }
-  fn b() { 2 }
-  fn a() { 3 }
-  "#;
-  let (_, output) = add_symbols_from_source(source);
-  assert!(output.unwrap_err().contains("Duplicate function definition: a"))
-}
-
-#[test]
-fn no_variable_definition_duplicates() {
-  let source = r#"
-  let x = 9
-  let a = 20
-  let q = 39
-  let a = 30
-  "#;
-  let (_, output) = add_symbols_from_source(source);
-  let output = output.unwrap_err();
-  assert!(output.contains("Duplicate variable definition: a"));
-  assert!(output.contains("already defined at 2"));
-}
-
-#[test]
-fn no_variable_definition_duplicates_in_function() {
-  let source = r#"
-  fn a() {
-    let a = 20
-    let b = 40
-    a + b
-  }
-
-  fn q() {
-    let a = 29
-    let x = 30
-    let x = 33
-  }
-  "#;
-  let (_, output) = add_symbols_from_source(source);
-  assert!(output.unwrap_err().contains("Duplicate variable definition: x"))
-}
-
-#[test]
-fn dont_falsely_detect_duplicates() {
-  let source = r#"
-  let a = 20;
-  fn some_func() {
-    let a = 40;
-    77
-  }
-  let q = 39;
-  "#;
-  let (symbol_table, _) = add_symbols_from_source(source);
-  assert!(symbol_table.lookup_by_fqsn(&fqsn!["a"; tr]).is_some());
-  assert!(symbol_table.lookup_by_fqsn(&fqsn!["some_func"; fn, "a";tr]).is_some());
-}
-
-#[test]
-fn enclosing_scopes() {
-  let source = r#"
-fn outer_func(x) {
-fn inner_func(arg) {
-  arg
-}
-x + inner_func(x)
-}"#;
-  let (symbol_table, _) = add_symbols_from_source(source);
-  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; tr)).is_some());
-  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "inner_func"; tr)).is_some());
-}
-
-#[test]
-fn enclosing_scopes_2() {
-  let source = r#"
-fn outer_func(x) {
-fn inner_func(arg) {
-  arg
-}
-
-fn second_inner_func() {
-  fn another_inner_func() {
-  }
-}
-
-inner_func(x)
-}"#;
-  let (symbol_table, _) = add_symbols_from_source(source);
-  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; tr)).is_some());
-  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "inner_func"; tr)).is_some());
-  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "second_inner_func"; tr)).is_some());
-  assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "second_inner_func"; fn, "another_inner_func"; tr)).is_some());
-}
-
-#[test]
-fn enclosing_scopes_3() {
-  let source = r#"
-fn outer_func(x) {
-fn inner_func(arg) {
-  arg
-}
-
-fn second_inner_func() {
-  fn another_inner_func() {
-  }
-  fn another_inner_func() {
-  }
-}
-
-inner_func(x)
-}"#;
-  let (_, output) = add_symbols_from_source(source);
-  assert!(output.unwrap_err().contains("Duplicate"))
-}
-
-#[test]
-fn modules() {
-  let source = r#"
-module stuff {
-  fn item() {
-  }
-}
-
-fn item()
-"#;
-  values_in_table! { source  =>
-    &fqsn!("item"; tr),
-    &fqsn!("stuff"; tr, "item"; tr)
-  };
-}
-
-#[test]
-fn duplicate_modules() {
-  let source = r#"
-    module q {
-      fn foo() { 4 }
-    }
-
-    module a {
-      fn foo() { 334 }
-    }
-
-    module a {
-      fn foo() { 256.1 }
-    }
-    "#;
-  let (_, output) = add_symbols_from_source(source);
-  let output = output.unwrap_err();
-  assert!(output.contains("Duplicate module"));
-  assert!(output.contains("already defined at 5"));
-}

schala-lang/language/src/tokenizing.rs

@@ -1,344 +0,0 @@
-use itertools::Itertools;
-use std::collections::HashMap;
-use std::rc::Rc;
-use std::iter::{Iterator, Peekable};
-use std::fmt;
-
-use crate::source_map::Location;
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum TokenKind {
-  Newline, Semicolon,
-
-  LParen, RParen,
-  LSquareBracket, RSquareBracket,
-  LAngleBracket, RAngleBracket,
-  LCurlyBrace, RCurlyBrace,
-  Pipe, Backslash,
-
-  Comma, Period, Colon, Underscore,
-  Slash, Equals,
-
-  Operator(Rc<String>),
-  DigitGroup(Rc<String>), HexLiteral(Rc<String>), BinNumberSigil,
-  StrLiteral {
-    s: Rc<String>,
-    prefix: Option<Rc<String>>
-  },
-  Identifier(Rc<String>),
-  Keyword(Kw),
-
-  EOF,
-
-  Error(String),
-}
-use self::TokenKind::*;
-
-impl fmt::Display for TokenKind {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    match self {
-      &Operator(ref s) => write!(f, "Operator({})", **s),
-      &DigitGroup(ref s) => write!(f, "DigitGroup({})", s),
-      &HexLiteral(ref s) => write!(f, "HexLiteral({})", s),
-      &StrLiteral {ref s, .. } => write!(f, "StrLiteral({})", s),
-      &Identifier(ref s) => write!(f, "Identifier({})", s),
-      &Error(ref s) => write!(f, "Error({})", s),
-      other => write!(f, "{:?}", other),
-    }
-  }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq)]
-pub enum Kw {
-  If, Then, Else,
-  Is,
-  Func,
-  For, While,
-  Const, Let, In,
-  Mut,
-  Return,
-  Alias, Type, SelfType, SelfIdent,
-  Interface, Impl,
-  True, False,
-  Module, Import
-}
-
-lazy_static! {
-  static ref KEYWORDS: HashMap<&'static str, Kw> =
-    hashmap! {
-      "if" => Kw::If,
-      "then" => Kw::Then,
-      "else" => Kw::Else,
-      "is" => Kw::Is,
-      "fn" => Kw::Func,
-      "for" => Kw::For,
-      "while" => Kw::While,
-      "const" => Kw::Const,
-      "let" => Kw::Let,
-      "in" => Kw::In,
-      "mut" => Kw::Mut,
-      "return" => Kw::Return,
-      "alias" => Kw::Alias,
-      "type" => Kw::Type,
-      "Self" => Kw::SelfType,
-      "self" => Kw::SelfIdent,
-      "interface" => Kw::Interface,
-      "impl" => Kw::Impl,
-      "true" => Kw::True,
-      "false" => Kw::False,
-      "module" => Kw::Module,
-      "import" => Kw::Import,
-    };
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct Token {
-  pub kind: TokenKind,
-  pub location: Location,
-}
-
-impl Token {
-  pub fn get_error(&self) -> Option<String> {
-    match self.kind {
-      TokenKind::Error(ref s) => Some(s.clone()),
-      _ => None,
-    }
-  }
-  pub fn to_string_with_metadata(&self) -> String {
-    format!("{}({})", self.kind, self.location)
-  }
-
-  pub fn get_kind(&self) -> TokenKind {
-    self.kind.clone()
-  }
-}
-
-const OPERATOR_CHARS: [char; 18] = ['!', '$', '%', '&', '*', '+', '-', '.', ':', '<', '>', '=', '?', '@', '^', '|', '~', '`'];
-fn is_operator(c: &char) -> bool {
-  OPERATOR_CHARS.iter().any(|x| x == c)
-}
-
-type CharData = (usize, usize, char);
-
-pub fn tokenize(input: &str) -> Vec<Token> {
-  let mut tokens: Vec<Token> = Vec::new();
-
-  let mut input = input.lines().enumerate()
-      .intersperse((0, "\n"))
-      .flat_map(|(line_idx, ref line)| {
-          line.chars().enumerate().map(move |(ch_idx, ch)| (line_idx, ch_idx, ch))
-      })
-      .peekable();
-
-  while let Some((line_num, char_num, c)) = input.next() {
-    let cur_tok_kind = match c {
-      '/' => match input.peek().map(|t| t.2) {
-        Some('/') => {
-          while let Some((_, _, c)) = input.next() {
-            if c == '\n' {
-              break;
-            }
-          }
-          continue;
-        },
-        Some('*') => {
-          input.next();
-          let mut comment_level = 1;
-          while let Some((_, _, c)) = input.next() {
-            if c == '*'  && input.peek().map(|t| t.2) == Some('/') {
-              input.next();
-              comment_level -= 1;
-            } else if c == '/' && input.peek().map(|t| t.2) == Some('*') {
-              input.next();
-              comment_level += 1;
-            }
-            if comment_level == 0 {
-              break;
-            }
-          }
-          continue;
-        },
-        _ => Slash
-      },
-      c if c.is_whitespace() && c != '\n' => continue,
-      '\n' => Newline, ';' => Semicolon,
-      ':' => Colon, ',' => Comma,
-      '(' => LParen, ')' => RParen,
-      '{' => LCurlyBrace, '}' => RCurlyBrace,
-      '[' => LSquareBracket, ']' => RSquareBracket,
-      '"' => handle_quote(&mut input, None),
-      '\\' => Backslash,
-      c if c.is_digit(10) => handle_digit(c, &mut input),
-      c if c.is_alphabetic() || c == '_' => handle_alphabetic(c, &mut input),
-      c if is_operator(&c) => handle_operator(c, &mut input),
-      unknown => Error(format!("Unexpected character: {}", unknown)),
-    };
-    let location = Location { line_num, char_num };
-    tokens.push(Token { kind: cur_tok_kind, location });
-  }
-  tokens
-}
-
-fn handle_digit(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
-  if c == '0' && input.peek().map_or(false, |&(_, _, c)| { c == 'x' }) {
-    input.next();
-    let rest: String = input.peeking_take_while(|&(_, _, ref c)| c.is_digit(16) || *c == '_').map(|(_, _, c)| { c }).collect();
-    HexLiteral(Rc::new(rest))
-  } else if c == '0' && input.peek().map_or(false, |&(_, _, c)| { c == 'b' }) {
-    input.next();
-    BinNumberSigil
-  } else {
-    let mut buf = c.to_string();
-    buf.extend(input.peeking_take_while(|&(_, _, ref c)| c.is_digit(10)).map(|(_, _, c)| { c }));
-    DigitGroup(Rc::new(buf))
-  }
-}
-
-fn handle_quote(input: &mut Peekable<impl Iterator<Item=CharData>>, quote_prefix: Option<&str>) -> TokenKind {
-  let mut buf = String::new();
-  loop {
-    match input.next().map(|(_, _, c)| { c }) {
-      Some('"') => break,
-      Some('\\') => {
-        let next = input.peek().map(|&(_, _, c)| { c });
-        if next == Some('n') {
-          input.next();
-          buf.push('\n')
-        } else if next == Some('"') {
-          input.next();
-          buf.push('"');
-        } else if next == Some('t') {
-          input.next();
-          buf.push('\t');
-        }
-      },
-      Some(c) => buf.push(c),
-      None => return TokenKind::Error(format!("Unclosed string")),
-    }
-  }
-  TokenKind::StrLiteral { s: Rc::new(buf), prefix: quote_prefix.map(|s| Rc::new(s.to_string())) }
-}
-
-fn handle_alphabetic(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
-  let mut buf = String::new();
-  buf.push(c);
-  if c == '_' && input.peek().map(|&(_, _, c)| { !c.is_alphabetic() }).unwrap_or(true) {
-    return TokenKind::Underscore
-  }
-
-  loop {
-    match input.peek().map(|&(_, _, c)| { c }) {
-      Some(c) if c == '"' => {
-        input.next();
-        return handle_quote(input, Some(&buf));
-      },
-      Some(c) if c.is_alphanumeric() || c == '_' => {
-        input.next();
-        buf.push(c);
-      },
-      _ => break,
-    }
-  }
-
-  match KEYWORDS.get(buf.as_str()) {
-    Some(kw) => TokenKind::Keyword(*kw),
-    None => TokenKind::Identifier(Rc::new(buf)),
-  }
-}
-
-fn handle_operator(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
-  match c {
-    '<' | '>' | '|' | '.' | '=' => {
-      let ref next = input.peek().map(|&(_, _, c)| { c });
-      if !next.map(|n| { is_operator(&n) }).unwrap_or(false) {
-        return match c {
-          '<' => LAngleBracket,
-          '>' => RAngleBracket,
-          '|' => Pipe,
-          '.' => Period,
-          '=' => Equals,
-          _ => unreachable!(),
-        }
-      }
-    },
-    _ => (),
-  };
-
-  let mut buf = String::new();
-
-  if c == '`' {
-    loop {
-      match input.peek().map(|&(_, _, c)| { c }) {
-        Some(c) if c.is_alphabetic() || c == '_' => {
-          input.next();
-          buf.push(c);
-        },
-        Some('`') => {
-          input.next();
-          break;
-        },
-        _ => break
-      }
-    }
-  } else {
-    buf.push(c);
-    loop {
-      match input.peek().map(|&(_, _, c)| { c }) {
-        Some(c) if is_operator(&c) => {
-          input.next();
-          buf.push(c);
-        },
-        _ => break
-      }
-    }
-  }
-  TokenKind::Operator(Rc::new(buf))
-}
-
-#[cfg(test)]
-mod schala_tokenizer_tests {
-  use super::*;
-  use super::Kw::*;
-
-  macro_rules! digit { ($ident:expr) => { DigitGroup(Rc::new($ident.to_string())) } }
-  macro_rules! ident { ($ident:expr) => { Identifier(Rc::new($ident.to_string())) } }
-  macro_rules! op { ($ident:expr) => { Operator(Rc::new($ident.to_string())) } }
-
-  #[test]
-  fn tokens() {
-    let a = tokenize("let a: A<B> = c ++ d");
-    let token_kinds: Vec<TokenKind> = a.into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![Keyword(Let), ident!("a"), Colon, ident!("A"),
-      LAngleBracket, ident!("B"), RAngleBracket, Equals, ident!("c"), op!("++"), ident!("d")]);
-  }
-
-  #[test]
-  fn underscores() {
-    let token_kinds: Vec<TokenKind> = tokenize("4_8").into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![digit!("4"), Underscore, digit!("8")]);
-
-    let token_kinds2: Vec<TokenKind> = tokenize("aba_yo").into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds2, vec![ident!("aba_yo")]);
-  }
-
-  #[test]
-  fn comments() {
-    let token_kinds: Vec<TokenKind> = tokenize("1  + /* hella /* bro */ */ 2").into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![digit!("1"), op!("+"), digit!("2")]);
-  }
-
-  #[test]
-  fn backtick_operators() {
-    let token_kinds: Vec<TokenKind> = tokenize("1 `plus` 2").into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![digit!("1"), op!("plus"), digit!("2")]);
-  }
-
-  #[test]
-  fn string_literals() {
-    let token_kinds: Vec<TokenKind> = tokenize(r#""some string""#).into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![StrLiteral { s: Rc::new("some string".to_string()), prefix: None }]);
-
-    let token_kinds: Vec<TokenKind> = tokenize(r#"b"some bytestring""#).into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![StrLiteral { s: Rc::new("some bytestring".to_string()), prefix: Some(Rc::new("b".to_string())) }]);
-  }
-}

schala-lang/language/src/type_check.rs

@@ -1,445 +0,0 @@
-use std::collections::HashMap;
-use std::rc::Rc;
-
-
-use parsing::{AST, Statement, Declaration, Signature, Expression, ExpressionType, Operation, Variant, TypeName, TypeSingletonName};
-
-// from Niko's talk
-/* fn type_check(expression, expected_ty) -> Ty {
-    let ty = bare_type_check(expression, expected_type);
-    if ty icompatible with expected_ty {
-        try_coerce(expression, ty, expected_ty)
-    } else {
-      ty
-    }
-  }
-
-  fn bare_type_check(exprssion, expected_type) -> Ty { ... }
- */
-
-/* H-M ALGO NOTES
-from https://www.youtube.com/watch?v=il3gD7XMdmA
-(also check out http://dev.stephendiehl.com/fun/006_hindley_milner.html)
-
-typeInfer :: Expr a -> Matching (Type a)
-unify :: Type a -> Type b -> Matching (Type c)
-
-(Matching a) is a monad in which unification is done
-
-ex:
-
-typeInfer (If e1 e2 e3) = do
-    t1 <- typeInfer e1
-    t2 <- typeInfer e2
-    t3 <- typeInfer e3
-    _ <- unify t1 BoolType
-    unify t2 t3 -- b/c t2 and t3 have to be the same type
-
-typeInfer (Const (ConstInt _)) = IntType -- same for other literals
-
---function application
-typeInfer (Apply f x) = do
-    tf <- typeInfer f
-    tx <- typeInfer x
-    case tf of
-        FunctionType t1 t2 -> do
-            _ <- unify t1 tx
-            return t2
-        _ -> fail "Not a function"
-
---type annotation
-typeInfer (Typed x t) = do
-    tx <- typeInfer x
-    unify tx t
-
---variable and let expressions - need to pass around a map of variable names to types here
-typeInfer :: [ (Var, Type Var) ] -> Expr Var -> Matching (Type Var)
-
-typeInfer ctx (Var x) = case (lookup x ctx) of
-    Just t -> return t
-    Nothing -> fail "Unknown variable"
-
---let x = e1 in e2
-typeInfer ctx (Let x e1 e2) = do
-    t1 <- typeInfer ctx e1
-    typeInfer ((x, t1) :: ctx) e2
-
---lambdas are complicated (this represents ʎx.e)
-typeInfer ctx (Lambda x e) = do
-    t1 <- allocExistentialVariable
-    t2 <- typeInfer ((x, t1) :: ctx) e
-    return $ FunctionType t1 t2 -- ie. t1 -> t2
-
-
---to solve the problem of map :: (a -> b) -> [a] -> [b]
-when we use a variable whose type has universal tvars, convert those universal
-tvars to existential ones
-    -and each  distinct universal tvar needs to map to the same existential type
-
--so we change typeinfer:
-typeInfer ctx (Var x) = do
-    case (lookup x ctx) of
-        Nothing -> ...
-        Just t -> do
-            let uvars = nub (toList t) -- nub removes duplicates, so this gets unique universally quantified variables
-            evars <- mapM (const allocExistentialVariable) uvars
-            let varMap = zip uvars evars
-            let vixVar varMap v = fromJust $ lookup v varMap
-            return (fmap (fixVar varMap) t)
-
---how do we define unify??
-
--recall, type signature is:
-unify :: Type a -> Type b -> Matching (Type c)
-unify BoolType BoolType = BoolType --easy, same for all constants
-unify (FunctionType t1 t2) (FunctionType t3 t4) = do
-    t5 <- unify t1 t3
-    t6 <- unify t2 t4
-    return $ FunctionType t5 t6
-unify (TVar a) (TVar b) = if a == b then TVar a else fail
---existential types can be assigned another type at most once
---some complicated stuff about hanlding existential types
---everything else is a type error
-unify a b = fail
-
-
-SKOLEMIZATION - how you prevent an unassigned existential type variable from leaking!
--before a type gets to global scope, replace all unassigned existential vars w/  new unique universal
-type variables
-
-*/
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Type {
-  TVar(TypeVar),
-  TConst(TypeConst),
-  TFunc(Box<Type>, Box<Type>),
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum TypeVar {
-  Univ(Rc<String>),
-  Exist(u64),
-}
-impl TypeVar {
-  fn univ(label: &str) -> TypeVar {
-    TypeVar::Univ(Rc::new(label.to_string()))
-  }
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum TypeConst {
-  UserT(Rc<String>),
-  Integer,
-  Float,
-  StringT,
-  Boolean,
-  Unit,
-  Bottom,
-}
-
-type TypeCheckResult = Result<Type, String>;
-
-#[derive(Debug, PartialEq, Eq, Hash)]
-struct PathSpecifier(Rc<String>);
-
-#[derive(Debug, PartialEq, Clone)]
-struct TypeContextEntry {
-  ty: Type,
-  constant: bool
-}
-
-pub struct TypeContext {
-  symbol_table: HashMap<PathSpecifier, TypeContextEntry>,
-  evar_table: HashMap<u64, Type>,
-  existential_type_label_count: u64
-}
-
-impl TypeContext {
-  pub fn new() -> TypeContext {
-    TypeContext {
-      symbol_table: HashMap::new(),
-      evar_table: HashMap::new(),
-      existential_type_label_count: 0,
-    }
-  }
-  pub fn add_symbols(&mut self, ast: &AST) {
-    use self::Declaration::*;
-    use self::Type::*;
-    use self::TypeConst::*;
-
-    for statement in ast.0.iter() {
-      match *statement {
-        Statement::ExpressionStatement(_) => (),
-        Statement::Declaration(ref decl) => match *decl {
-          FuncSig(_) => (),
-          Impl { .. } => (),
-          TypeDecl(ref type_constructor, ref body) => {
-            for variant in body.0.iter() {
-              let (spec, ty) = match variant {
-                &Variant::UnitStruct(ref data_constructor) => {
-                  let spec = PathSpecifier(data_constructor.clone());
-                  let ty = TConst(UserT(type_constructor.name.clone()));
-                  (spec, ty)
-                },
-                &Variant::TupleStruct(ref data_construcor, ref args) => {
-                  //TODO fix
-                  let arg = args.get(0).unwrap();
-                  let type_arg = self.from_anno(arg);
-                  let spec = PathSpecifier(data_construcor.clone());
-                  let ty = TFunc(Box::new(type_arg), Box::new(TConst(UserT(type_constructor.name.clone()))));
-                  (spec, ty)
-                },
-                &Variant::Record(_, _) => unimplemented!(),
-              };
-              let entry = TypeContextEntry { ty, constant: true };
-              self.symbol_table.insert(spec, entry);
-            }
-          },
-          TypeAlias { .. } => (),
-          Binding {ref name, ref constant, ref expr} => {
-            let spec = PathSpecifier(name.clone());
-            let ty = expr.1.as_ref()
-              .map(|ty| self.from_anno(ty))
-              .unwrap_or_else(|| { self.alloc_existential_type() }); // this call to alloc_existential is OK b/c a binding only ever has one type, so if the annotation is absent, it's fine to just make one de novo
-            let entry = TypeContextEntry { ty, constant: *constant };
-            self.symbol_table.insert(spec, entry);
-          },
-          FuncDecl(ref signature, _) => {
-            let spec = PathSpecifier(signature.name.clone());
-            let ty = self.from_signature(signature);
-            let entry = TypeContextEntry { ty, constant: true };
-            self.symbol_table.insert(spec, entry);
-          },
-        }
-      }
-    }
-  }
-  fn lookup(&mut self, binding: &Rc<String>) -> Option<TypeContextEntry> {
-    let key = PathSpecifier(binding.clone());
-    self.symbol_table.get(&key).map(|entry| entry.clone())
-  }
-  pub fn debug_symbol_table(&self) -> String  {
-    format!("Symbol table:\n {:?}\nEvar table:\n{:?}", self.symbol_table, self.evar_table)
-  }
-  fn alloc_existential_type(&mut self) -> Type {
-    let ret = Type::TVar(TypeVar::Exist(self.existential_type_label_count));
-    self.existential_type_label_count += 1;
-    ret
-  }
-
-  fn from_anno(&mut self, anno: &TypeName) -> Type {
-    use self::Type::*;
-    use self::TypeConst::*;
-
-    match anno {
-      &TypeName::Singleton(TypeSingletonName { ref name, .. }) => {
-        match name.as_ref().as_ref() {
-          "Int" => TConst(Integer),
-          "Float" => TConst(Float),
-          "Bool" => TConst(Boolean),
-          "String" => TConst(StringT),
-          s => TVar(TypeVar::Univ(Rc::new(format!("{}",s)))),
-        }
-      },
-      &TypeName::Tuple(ref items) => {
-        if items.len() == 1 {
-          TConst(Unit)
-        } else {
-          TConst(Bottom)
-        }
-      }
-    }
-  }
-
-  fn from_signature(&mut self, sig: &Signature) -> Type {
-    use self::Type::*;
-    use self::TypeConst::*;
-
-    //TODO this won't work properly until you make sure that all (universal) type vars in the function have the same existential type var
-    // actually this should never even put existential types into the symbol table at all
-
-    //this will crash if more than 5 arg function is used
-    let names = vec!["a", "b", "c", "d", "e", "f"];
-    let mut idx = 0;
-    
-    let mut get_type = || { let q = TVar(TypeVar::Univ(Rc::new(format!("{}", names.get(idx).unwrap())))); idx += 1; q };
-
-    let return_type = sig.type_anno.as_ref().map(|anno| self.from_anno(&anno)).unwrap_or_else(|| { get_type() });
-    if sig.params.len() == 0 {
-      TFunc(Box::new(TConst(Unit)), Box::new(return_type))
-    } else {
-      let mut output_type = return_type;
-      for p in sig.params.iter() {
-        let p_type = p.1.as_ref().map(|anno| self.from_anno(anno)).unwrap_or_else(|| { get_type() });
-        output_type = TFunc(Box::new(p_type), Box::new(output_type));
-      }
-      output_type
-    }
-  }
-
-  pub fn type_check(&mut self, ast: &AST) -> TypeCheckResult {
-    use self::Type::*;
-    use self::TypeConst::*;
-
-    let mut last = TConst(Unit);
-
-    for statement in ast.0.iter() {
-      match statement {
-        &Statement::Declaration(ref _decl) => {
-          //return Err(format!("Declarations not supported"));
-        },
-        &Statement::ExpressionStatement(ref expr) => {
-          last = self.infer(expr)?;
-        }
-      }
-    }
-    Ok(last)
-  }
-  fn infer(&mut self, expr: &Expression) -> TypeCheckResult {
-    match (&expr.0, &expr.1) {
-      (exprtype, &Some(ref anno)) => {
-        let tx = self.infer_no_anno(exprtype)?;
-        let ty = self.from_anno(anno);
-        self.unify(tx, ty)
-      },
-      (exprtype, &None) => self.infer_no_anno(exprtype),
-    }
-  }
-
-  fn infer_no_anno(&mut self, ex: &ExpressionType) -> TypeCheckResult { 
-    use self::ExpressionType::*;
-    use self::Type::*;
-    use self::TypeConst::*;
-
-    Ok(match ex {
-      &IntLiteral(_) => TConst(Integer),
-      &FloatLiteral(_) => TConst(Float),
-      &StringLiteral(_) => TConst(StringT),
-      &BoolLiteral(_) => TConst(Boolean),
-      &Value(ref name, _) => {
-        self.lookup(name)
-          .map(|entry| entry.ty)
-          .ok_or(format!("Couldn't find {}", name))?
-      },
-      &BinExp(ref op, ref lhs, ref rhs) => {
-        let t_lhs = self.infer(lhs)?;
-        match self.infer_op(op)? {
-          TFunc(t1, t2) => {
-            let _ = self.unify(t_lhs, *t1)?;
-            let t_rhs = self.infer(rhs)?;
-            let x = *t2;
-            match x {
-              TFunc(t3, t4) => {
-                let _ = self.unify(t_rhs, *t3)?;
-                *t4
-              },
-              _ => return Err(format!("Not a function type either")),
-            }
-          },
-          _ => return Err(format!("Op {:?} is not a function type", op)),
-        }
-      },
-      &Call { ref f, ref arguments } => {
-        let tf = self.infer(f)?;
-        let targ = self.infer(arguments.get(0).unwrap())?;
-        match tf {
-          TFunc(box t1, box t2) => {
-            let _ = self.unify(t1, targ)?;
-            t2
-          },
-          _ => return Err(format!("Not a function!")),
-        }
-      },
-      _ => TConst(Bottom),
-    })
-  }
-
-  fn infer_op(&mut self, op: &Operation) -> TypeCheckResult {
-    use self::Type::*;
-    use self::TypeConst::*;
-    macro_rules! binoptype {
-      ($lhs:expr, $rhs:expr, $out:expr) => { TFunc(Box::new($lhs), Box::new(TFunc(Box::new($rhs), Box::new($out)))) };
-    }
-
-    Ok(match (*op.0).as_ref() {
-      "+" => binoptype!(TConst(Integer), TConst(Integer), TConst(Integer)),
-      "++" => binoptype!(TConst(StringT), TConst(StringT), TConst(StringT)),
-      "-" => binoptype!(TConst(Integer), TConst(Integer), TConst(Integer)),
-      "*" => binoptype!(TConst(Integer), TConst(Integer), TConst(Integer)),
-      "/" => binoptype!(TConst(Integer), TConst(Integer), TConst(Integer)),
-      "%" => binoptype!(TConst(Integer), TConst(Integer), TConst(Integer)),
-      _ => TConst(Bottom)
-    })
-  }
-
-  fn unify(&mut self, t1: Type, t2: Type) -> TypeCheckResult {
-    use self::Type::*;
-    use self::TypeVar::*;
-
-    println!("Calling unify with `{:?}` and `{:?}`", t1, t2);
-
-    match (&t1, &t2) {
-      (&TConst(ref c1), &TConst(ref c2)) if c1 == c2 => Ok(TConst(c1.clone())),
-      (&TFunc(ref t1, ref t2), &TFunc(ref t3, ref t4)) => {
-        let t5 = self.unify(*t1.clone().clone(), *t3.clone().clone())?;
-        let t6 = self.unify(*t2.clone().clone(), *t4.clone().clone())?;
-        Ok(TFunc(Box::new(t5), Box::new(t6)))
-      },
-      (&TVar(Univ(ref a)), &TVar(Univ(ref b))) => {
-        if a == b {
-          Ok(TVar(Univ(a.clone())))
-        } else {
-          Err(format!("Couldn't unify universal types {} and {}", a, b))
-        }
-      },
-      //the interesting case!!
-      (&TVar(Exist(ref a)), ref t2) => {
-        let x = self.evar_table.get(a).map(|x| x.clone());
-        match x {
-          Some(ref t1) => self.unify(t1.clone().clone(), t2.clone().clone()),
-          None => {
-            self.evar_table.insert(*a, t2.clone().clone());
-            Ok(t2.clone().clone())
-          }
-        }
-      },
-      (ref t1, &TVar(Exist(ref a))) => {
-        let x = self.evar_table.get(a).map(|x| x.clone());
-        match x {
-          Some(ref t2) => self.unify(t2.clone().clone(), t1.clone().clone()),
-          None => {
-            self.evar_table.insert(*a, t1.clone().clone());
-            Ok(t1.clone().clone())
-          }
-        }
-      },
-      _ => Err(format!("Types {:?} and {:?} don't unify", t1, t2))
-    }
-  }
-}
-
-#[cfg(test)]
-mod tests {
-  use super::{Type, TypeVar, TypeConst, TypeContext};
-  use super::Type::*;
-  use super::TypeConst::*;
-  use schala_lang::parsing::{parse, tokenize};
-
-  macro_rules! type_test {
-    ($input:expr, $correct:expr) => {
-      {
-      let mut tc = TypeContext::new();
-      let ast = parse(tokenize($input)).0.unwrap() ;
-      tc.add_symbols(&ast);
-      assert_eq!($correct, tc.type_check(&ast).unwrap())
-      }
-    }
-  }
-
-  #[test]
-  fn basic_inference() {
-    type_test!("30", TConst(Integer));
-    type_test!("fn x(a: Int): Bool {}; x(1)", TConst(Boolean));
-  }
-}

schala-lang/language/src/typechecking.rs

@@ -1,488 +0,0 @@
-use std::rc::Rc;
-use std::fmt::Write;
-
-use ena::unify::{UnifyKey, InPlaceUnificationTable, UnificationTable, EqUnifyValue};
-
-use crate::ast::*;
-use crate::util::ScopeStack;
-use crate::util::deref_optional_box;
-
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct TypeData {
-  ty: Option<Type>
-}
-
-impl TypeData {
-  #[allow(dead_code)]
-  pub fn new() -> TypeData {
-    TypeData { ty: None }
-  }
-}
-
-pub type TypeName = Rc<String>;
-
-pub struct TypeContext<'a> {
-  variable_map: ScopeStack<'a, Rc<String>, Type>,
-  unification_table: InPlaceUnificationTable<TypeVar>,
-}
-
-/// `InferResult` is the monad in which type inference takes place.
-type InferResult<T> = Result<T, TypeError>;
-
-#[derive(Debug, Clone)]
-pub struct TypeError { pub msg: String }
-
-impl TypeError {
-  fn new<A, T>(msg: T) -> InferResult<A> where T: Into<String> {
-    Err(TypeError { msg: msg.into() })
-  }
-}
-
-#[allow(dead_code)] // avoids warning from Compound
-#[derive(Debug, Clone, PartialEq)]
-pub enum Type {
-  Const(TypeConst),
-  Var(TypeVar),
-  Arrow {
-    params: Vec<Type>,
-    ret: Box<Type>
-  },
-  Compound {
-    ty_name: String,
-    args:Vec<Type>
-  }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct TypeVar(usize);
-
-impl UnifyKey for TypeVar {
-  type Value = Option<TypeConst>;
-  fn index(&self) -> u32 { self.0 as u32 }
-  fn from_index(u: u32) -> TypeVar { TypeVar(u as usize) }
-  fn tag() -> &'static str { "TypeVar" }
-}
-
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub enum TypeConst {
-  Unit,
-  Nat,
-  Int,
-  Float,
-  StringT,
-  Bool,
-  Ordering,
-  //UserDefined
-}
-
-impl TypeConst {
-  pub fn to_string(&self) -> String {
-    use self::TypeConst::*;
-    match self {
-      Unit => format!("()"),
-      Nat => format!("Nat"),
-      Int => format!("Int"),
-      Float => format!("Float"),
-      StringT => format!("String"),
-      Bool => format!("Bool"),
-      Ordering => format!("Ordering"),
-    }
-  }
-}
-
-impl EqUnifyValue for TypeConst { }
-
-macro_rules! ty {
-  ($type_name:ident) => { Type::Const(TypeConst::$type_name) };
-  ($t1:ident -> $t2:ident) => { Type::Arrow { params: vec![ty!($t1)], ret: box ty!($t2) } };
-  ($t1:ident -> $t2:ident -> $t3:ident) => { Type::Arrow { params: vec![ty!($t1), ty!($t2)], ret: box ty!($t3) } };
-  ($type_list:ident, $ret_type:ident) => {
-    Type::Arrow {
-      params: $type_list,
-      ret: box $ret_type,
-    }
-  }
-}
-
-//TODO find a better way to capture the to/from string logic
-impl Type {
-  pub fn to_string(&self) -> String {
-    use self::Type::*;
-    match self {
-      Const(c) => c.to_string(),
-      Var(v) => format!("t_{}", v.0),
-      Arrow { params, box ref ret } => {
-        if params.len() == 0 {
-          format!("-> {}", ret.to_string())
-        } else {
-          let mut buf = String::new();
-          for p in params.iter() {
-            write!(buf, "{} -> ", p.to_string()).unwrap();
-          }
-          write!(buf, "{}", ret.to_string()).unwrap();
-          buf
-        }
-      },
-      Compound { .. } => format!("<some compound type>")
-    }
-  }
-
-  fn from_string(string: &str) -> Option<Type> {
-    Some(match string {
-      "()" | "Unit" => ty!(Unit),
-      "Nat" => ty!(Nat),
-      "Int" => ty!(Int),
-      "Float" => ty!(Float),
-      "String" => ty!(StringT),
-      "Bool" => ty!(Bool),
-      "Ordering" => ty!(Ordering),
-      _ => return None
-    })
-  }
-}
-
-/*
-/// `Type` is parameterized by whether the type variables can be just universal, or universal or
-/// existential.
-#[derive(Debug, Clone)]
-enum Type<A> {
-  Var(A),
-  Const(TConst),
-  Arrow(Box<Type<A>>, Box<Type<A>>),
-}
-
-#[derive(Debug, Clone)]
-enum TVar {
-  Univ(UVar),
-  Exist(ExistentialVar)
-}
-
-#[derive(Debug, Clone)]
-struct UVar(Rc<String>);
-
-#[derive(Debug, Clone)]
-struct ExistentialVar(u32);
-
-impl Type<UVar> {
-  fn to_tvar(&self) -> Type<TVar> {
-    match self {
-      Type::Var(UVar(name)) => Type::Var(TVar::Univ(UVar(name.clone()))),
-      Type::Const(ref c) => Type::Const(c.clone()),
-      Type::Arrow(a, b) => Type::Arrow(
-        Box::new(a.to_tvar()),
-        Box::new(b.to_tvar())
-      )
-    }
-  }
-}
-
-impl Type<TVar> {
-  fn skolemize(&self) -> Type<UVar> {
-    match self {
-      Type::Var(TVar::Univ(uvar)) => Type::Var(uvar.clone()),
-      Type::Var(TVar::Exist(_)) => Type::Var(UVar(Rc::new(format!("sk")))),
-      Type::Const(ref c) => Type::Const(c.clone()),
-      Type::Arrow(a, b) => Type::Arrow(
-        Box::new(a.skolemize()),
-        Box::new(b.skolemize())
-      )
-    }
-  }
-}
-
-impl TypeIdentifier {
-  fn to_monotype(&self) -> Type<UVar> {
-    match self {
-      TypeIdentifier::Tuple(_) => Type::Const(TConst::Nat),
-      TypeIdentifier::Singleton(TypeSingletonName { name, .. }) => {
-        match &name[..] {
-          "Nat" => Type::Const(TConst::Nat),
-          "Int" => Type::Const(TConst::Int),
-          "Float" => Type::Const(TConst::Float),
-          "Bool" => Type::Const(TConst::Bool),
-          "String" => Type::Const(TConst::StringT),
-          _ => Type::Const(TConst::Nat),
-        }
-      }
-    }
-  }
-}
-
-#[derive(Debug, Clone)]
-enum TConst {
-  User(Rc<String>),
-  Unit,
-  Nat,
-  Int,
-  Float,
-  StringT,
-  Bool,
-}
-
-impl TConst {
-  fn user(name: &str) -> TConst {
-    TConst::User(Rc::new(name.to_string()))
-  }
-}
-*/
-
-impl<'a> TypeContext<'a> {
-  pub fn new() -> TypeContext<'a> {
-    TypeContext { 
-      variable_map: ScopeStack::new(None),
-      unification_table: UnificationTable::new(),
-    }
-  }
-
-  /*
-  fn new_env(&'a self, new_var: Rc<String>, ty: Type) -> TypeContext<'a> {
-    let mut new_context = TypeContext {
-      variable_map: self.variable_map.new_scope(None),
-      unification_table: UnificationTable::new(), //???? not sure if i want this
-    };
-
-    new_context.variable_map.insert(new_var, ty);
-    new_context
-  }
-  */
-
-
-  fn get_type_from_name(&self, name: &TypeIdentifier) -> InferResult<Type> {
-    use self::TypeIdentifier::*;
-    Ok(match name {
-      Singleton(TypeSingletonName { name,.. }) =>  {
-        match Type::from_string(&name) {
-          Some(ty) => ty,
-          None => return TypeError::new(format!("Unknown type name: {}", name))
-        }
-      },
-      Tuple(_) => return TypeError::new("tuples aren't ready yet"),
-    })
-  }
-
-  /// `typecheck` is the entry into the type-inference system, accepting an AST as an argument
-  /// Following the example of GHC, the compiler deliberately does typechecking before de-sugaring
-  /// the AST to ReducedAST
-  pub fn typecheck(&mut self, ast: &AST) -> Result<Type, TypeError> {
-    let mut returned_type = Type::Const(TypeConst::Unit);
-    for statement in ast.statements.iter() {
-      returned_type = self.statement(statement)?;
-    }
-    Ok(returned_type)
-  }
-
-  fn statement(&mut self, statement: &Statement) -> InferResult<Type> {
-    match &statement.kind {
-      StatementKind::Expression(e) => self.expr(e),
-      StatementKind::Declaration(decl) => self.decl(&decl),
-      StatementKind::Import(_) => Ok(ty!(Unit)),
-      StatementKind::Module(_) => Ok(ty!(Unit)),
-    }
-  }
-
-  fn decl(&mut self, decl: &Declaration) -> InferResult<Type> {
-    use self::Declaration::*;
-    match decl {
-      Binding { name, expr, .. } => {
-        let ty = self.expr(expr)?;
-        self.variable_map.insert(name.clone(), ty);
-      },
-      _ => (),
-    }
-    Ok(ty!(Unit))
-  }
-
-  fn invoc(&mut self, invoc: &InvocationArgument) -> InferResult<Type> {
-    use InvocationArgument::*;
-    match invoc {
-      Positional(expr) => self.expr(expr),
-      _ => Ok(ty!(Nat)) //TODO this is wrong
-    }
-  }
-
-  fn expr(&mut self, expr: &Expression) -> InferResult<Type> {
-    match expr {
-      Expression { kind, type_anno: Some(anno), .. } => {
-        let t1 = self.expr_type(kind)?;
-        let t2 = self.get_type_from_name(anno)?;
-        self.unify(t2, t1)
-      },
-      Expression { kind, type_anno: None, .. } => self.expr_type(kind)
-    }
-  }
-
-  fn expr_type(&mut self, expr: &ExpressionKind) -> InferResult<Type> {
-    use self::ExpressionKind::*;
-    Ok(match expr {
-      NatLiteral(_) => ty!(Nat),
-      BoolLiteral(_) => ty!(Bool),
-      FloatLiteral(_) => ty!(Float),
-      StringLiteral(_) => ty!(StringT),
-      PrefixExp(op, expr) => self.prefix(op, expr)?,
-      BinExp(op, lhs, rhs) => self.binexp(op, lhs, rhs)?,
-      IfExpression { discriminator, body } => self.if_expr(deref_optional_box(discriminator), &**body)?,
-      Value(val) => self.handle_value(val)?,
-      Call { box ref f, arguments } => self.call(f, arguments)?,
-      Lambda { params, type_anno, body } => self.lambda(params, type_anno, body)?,
-      _ => ty!(Unit),
-    })
-  }
-
-  fn prefix(&mut self, op: &PrefixOp, expr: &Expression) -> InferResult<Type> {
-    let tf = match op.builtin.map(|b| b.get_type()) {
-      Some(ty) => ty,
-      None => return TypeError::new("no type found")
-    };
-
-    let tx = self.expr(expr)?;
-    self.handle_apply(tf, vec![tx])
-  }
-
-  fn binexp(&mut self, op: &BinOp, lhs: &Expression, rhs: &Expression) -> InferResult<Type> {
-    let tf = match op.builtin.map(|b| b.get_type()) {
-      Some(ty) => ty,
-      None => return TypeError::new("no type found"),
-    };
-
-    let t_lhs = self.expr(lhs)?;
-    let t_rhs = self.expr(rhs)?; //TODO is this order a problem? not sure
-
-    self.handle_apply(tf, vec![t_lhs, t_rhs])
-  }
-
-  fn if_expr(&mut self, discriminator: Option<&Expression>, body: &IfExpressionBody) -> InferResult<Type> {
-    use self::IfExpressionBody::*;
-    match (discriminator, body) {
-      (Some(expr), SimpleConditional{ then_case, else_case }) => self.handle_simple_if(expr, then_case, else_case),
-      _ => TypeError::new(format!("Complex conditionals not supported"))
-    }
-  }
-
-  fn handle_simple_if(&mut self, expr: &Expression, then_clause: &Block, else_clause: &Option<Block>) -> InferResult<Type> {
-    let t1 = self.expr(expr)?;
-    let t2 = self.block(then_clause)?;
-    let t3 = match else_clause {
-      Some(block) => self.block(block)?,
-      None => ty!(Unit)
-    };
-
-    let _ = self.unify(ty!(Bool), t1)?;
-    self.unify(t2, t3)
-  }
-
-  fn lambda(&mut self, params: &Vec<FormalParam>, type_anno: &Option<TypeIdentifier>, _body: &Block) -> InferResult<Type> {
-    let argument_types: InferResult<Vec<Type>> = params.iter().map(|param: &FormalParam| {
-      if let FormalParam { anno: Some(type_identifier), ..  } = param {
-        self.get_type_from_name(type_identifier)
-      } else {
-        Ok(Type::Var(self.fresh_type_variable()))
-      }
-    }).collect();
-    let argument_types = argument_types?;
-    let ret_type = match type_anno.as_ref() {
-      Some(anno) => self.get_type_from_name(anno)?,
-      None => Type::Var(self.fresh_type_variable())
-    };
-
-    Ok(ty!(argument_types, ret_type))
-  }
-
-  fn call(&mut self, f: &Expression, args: &Vec<InvocationArgument>) -> InferResult<Type> {
-    let tf = self.expr(f)?;
-    let arg_types: InferResult<Vec<Type>> = args.iter().map(|ex| self.invoc(ex)).collect();
-    let arg_types = arg_types?;
-    self.handle_apply(tf, arg_types)
-  }
-
-  fn handle_apply(&mut self, tf: Type, args: Vec<Type>) -> InferResult<Type> {
-    Ok(match tf {
-      Type::Arrow { ref params, ret: box ref t_ret } if params.len() == args.len() => {
-        for (t_param, t_arg) in params.iter().zip(args.iter()) {
-          let _ = self.unify(t_param.clone(), t_arg.clone())?; //TODO I think this needs to reference a sub-scope
-        }
-        t_ret.clone()
-      },
-      Type::Arrow { .. } => return TypeError::new("Wrong length"),
-      _ => return TypeError::new(format!("Not a function"))
-    })
-  }
-
-  fn block(&mut self, block: &Block) -> InferResult<Type> {
-    let mut output = ty!(Unit);
-    for statement in block.iter() {
-      output = self.statement(statement)?;
-    }
-    Ok(output)
-  }
-
-  fn handle_value(&mut self, val: &QualifiedName) -> InferResult<Type> {
-    let QualifiedName { components: vec, .. } = val;
-    let var = &vec[0];
-    match self.variable_map.lookup(var) {
-      Some(ty) => Ok(ty.clone()),
-      None => TypeError::new(format!("Couldn't find variable: {}", &var)),
-    }
-  }
-
-  fn unify(&mut self, t1: Type, t2: Type) -> InferResult<Type> {
-    use self::Type::*;
-
-    match (t1, t2) {
-      (Const(ref c1), Const(ref c2)) if c1 == c2 => Ok(Const(c1.clone())), //choice of c1 is arbitrary I *think*
-      (a @ Var(_), b @ Const(_)) => self.unify(b, a),
-      (Const(ref c1), Var(ref v2)) => {
-        self.unification_table.unify_var_value(v2.clone(), Some(c1.clone()))
-          .or_else(|_| TypeError::new(format!("Couldn't unify {:?} and {:?}", Const(c1.clone()), Var(*v2))))?;
-        Ok(Const(c1.clone()))
-      },
-      (Var(v1), Var(v2)) => {
-        //TODO add occurs check
-        self.unification_table.unify_var_var(v1.clone(), v2.clone())
-          .or_else(|e| {
-            println!("Unify error: {:?}", e);
-            TypeError::new(format!("Two type variables {:?} and {:?} couldn't unify", v1, v2))
-          })?;
-        Ok(Var(v1.clone())) //arbitrary decision I think
-      },
-      (a, b) => TypeError::new(format!("{:?} and {:?} do not unify", a, b)),
-    }
-  }
-
-  fn fresh_type_variable(&mut self) -> TypeVar {
-    let new_type_var = self.unification_table.new_key(None);
-    new_type_var
-  }
-}
-
-#[cfg(test)]
-mod typechecking_tests {
-  use super::*;
-
-  macro_rules! assert_type_in_fresh_context {
-    ($string:expr, $type:expr) => {
-      let mut tc = TypeContext::new();
-      let (ref ast, _) = crate::util::quick_ast($string);
-      let ty = tc.typecheck(ast).unwrap();
-      assert_eq!(ty, $type)
-    }
-  }
-
-  #[test]
-  fn basic_test() {
-    assert_type_in_fresh_context!("1", ty!(Nat));
-    assert_type_in_fresh_context!(r#""drugs""#, ty!(StringT));
-    assert_type_in_fresh_context!("true", ty!(Bool));
-  }
-
-  #[test]
-  fn operators() {
-    //TODO fix these with new operator regime
-    /*
-    assert_type_in_fresh_context!("-1", ty!(Int));
-    assert_type_in_fresh_context!("1 + 2", ty!(Nat));
-    assert_type_in_fresh_context!("-2", ty!(Int));
-    assert_type_in_fresh_context!("!true", ty!(Bool));
-    */
-  }
-}

schala-lang/language/src/util.rs

@@ -1,68 +0,0 @@
-use std::collections::HashMap;
-use std::hash::Hash;
-use std::cmp::Eq;
-use std::ops::Deref;
-
-pub fn deref_optional_box<T>(x: &Option<Box<T>>) -> Option<&T> {
-  x.as_ref().map(|b: &Box<T>| Deref::deref(b))
-}
-
-#[derive(Default, Debug)]
-pub struct ScopeStack<'a, T: 'a, V: 'a>  where T: Hash + Eq {
-  parent: Option<&'a ScopeStack<'a, T, V>>,
-  values: HashMap<T, V>,
-  scope_name: Option<String>
-}
-
-impl<'a, T, V> ScopeStack<'a, T, V> where T: Hash + Eq {
-  pub fn new(name: Option<String>) -> ScopeStack<'a, T, V> where T: Hash + Eq {
-    ScopeStack {
-      parent: None,
-      values: HashMap::new(),
-      scope_name: name
-    }
-  }
-  pub fn insert(&mut self, key: T, value: V) where T: Hash + Eq {
-    self.values.insert(key, value);
-  }
-  pub fn lookup(&self, key: &T) -> Option<&V> where T: Hash + Eq {
-    match (self.values.get(key), self.parent) {
-      (None, None) => None,
-      (None, Some(parent)) => parent.lookup(key),
-      (Some(value), _) => Some(value),
-    }
-  }
-
-  pub fn new_scope(&'a self, name: Option<String>) -> ScopeStack<'a, T, V> where T: Hash + Eq {
-    ScopeStack {
-      parent: Some(self),
-      values: HashMap::default(),
-      scope_name: name,
-    }
-  }
-  #[allow(dead_code)]
-  pub fn get_name(&self) -> Option<&String> {
-    self.scope_name.as_ref()
-  }
-}
-
-/// this is intended for use in tests, and does no error-handling whatsoever
-#[allow(dead_code)]
-pub fn quick_ast(input: &str) -> (crate::ast::AST, crate::source_map::SourceMap) {
-  use std::cell::RefCell;
-  use std::rc::Rc;
-
-  let source_map = crate::source_map::SourceMap::new();
-  let source_map_handle = Rc::new(RefCell::new(source_map));
-  let tokens = crate::tokenizing::tokenize(input);
-  let mut parser = crate::parsing::Parser::new(source_map_handle.clone());
-  parser.add_new_tokens(tokens);
-  let output = parser.parse();
-  std::mem::drop(parser);
-  (output.unwrap(), Rc::try_unwrap(source_map_handle).map_err(|_| ()).unwrap().into_inner())
-}
-
-#[allow(unused_macros)]
-macro_rules! rc {
-  ($string:tt) => { Rc::new(stringify!($string).to_string()) }
-}

schala-main/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "schala-main"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

schala-main/src/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!("Schala");
+}

schala-parser/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "schala-parser"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

schala-parser/src/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!("Hello, world!");
+}

schala-repl/Cargo.toml

@@ -1,24 +0,0 @@
-[package]
-name = "schala-repl"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-edition = "2018"
-
-[dependencies]
-llvm-sys = "70.0.2"
-take_mut = "0.2.2"
-itertools = "0.5.8"
-getopts = "0.2.18"
-lazy_static = "0.2.8"
-maplit = "*"
-colored = "1.8"
-serde = "1.0.91"
-serde_derive = "1.0.91"
-serde_json = "1.0.15"
-phf = "0.7.12"
-includedir = "0.2.0"
-linefeed = "0.6.0"
-regex = "0.2"
-
-[build-dependencies]
-includedir_codegen = "0.2.0"

schala-repl/build.rs

@@ -1,10 +0,0 @@
-extern crate includedir_codegen;
-
-use includedir_codegen::Compression;
-
-fn main() {
-    includedir_codegen::start("WEBFILES")
-        .dir("../static", Compression::Gzip)
-        .build("static.rs")
-        .unwrap();
-}

schala-repl/src/language.rs

@@ -1,80 +0,0 @@
-use std::time;
-use std::collections::HashSet;
-
-pub trait ProgrammingLanguageInterface {
-  fn get_language_name(&self) -> String;
-  fn get_source_file_suffix(&self) -> String;
-
-  fn run_computation(&mut self, _request: ComputationRequest) -> ComputationResponse {
-    ComputationResponse {
-      main_output: Err(format!("Computation pipeline not implemented")),
-      global_output_stats: GlobalOutputStats::default(),
-      debug_responses: vec![],
-    }
-  }
-
-  fn request_meta(&mut self, _request: LangMetaRequest) -> LangMetaResponse {
-    LangMetaResponse::Custom { kind: format!("not-implemented"), value: format!("") }
-  }
-}
-
-pub struct ComputationRequest<'a> {
-  pub source: &'a str,
-  pub debug_requests: HashSet<DebugAsk>,
-}
-
-pub struct ComputationResponse {
-  pub main_output: Result<String, String>,
-  pub global_output_stats: GlobalOutputStats,
-  pub debug_responses: Vec<DebugResponse>,
-}
-
-#[derive(Default, Debug)]
-pub struct GlobalOutputStats {
-  pub total_duration: time::Duration,
-  pub stage_durations: Vec<(String, time::Duration)>
-}
-
-#[derive(Debug, Clone, Hash, Eq, PartialEq, Deserialize, Serialize)]
-pub enum DebugAsk {
-  Timing,
-  ByStage { stage_name: String, token: Option<String> },
-}
-
-impl DebugAsk {
-  pub fn is_for_stage(&self, name: &str) -> bool {
-    match self {
-      DebugAsk::ByStage { stage_name, .. } if stage_name == name => true,
-      _ => false
-    }
-  }
-}
-
-pub struct DebugResponse {
-  pub ask: DebugAsk,
-  pub value: String
-}
-
-pub enum LangMetaRequest {
-  StageNames,
-  Docs {
-    source: String,
-  },
-  Custom {
-    kind: String,
-    value: String
-  },
-  ImmediateDebug(DebugAsk),
-}
-
-pub enum LangMetaResponse {
-  StageNames(Vec<String>),
-  Docs {
-    doc_string: String,
-  },
-  Custom {
-    kind: String,
-    value: String
-  },
-  ImmediateDebug(DebugResponse),
-}

schala-repl/src/lib.rs

@@ -1,92 +0,0 @@
-#![feature(link_args)]
-#![feature(slice_patterns, box_patterns, box_syntax, proc_macro_hygiene, decl_macro)]
-#![feature(plugin)]
-extern crate getopts;
-extern crate linefeed;
-extern crate itertools;
-extern crate colored;
-
-#[macro_use]
-extern crate serde_derive;
-extern crate serde_json;
-extern crate includedir;
-extern crate phf;
-
-use std::collections::HashSet;
-use std::path::Path;
-use std::fs::File;
-use std::io::Read;
-use std::process::exit;
-
-mod repl;
-mod language;
-
-pub use language::{ProgrammingLanguageInterface,
-ComputationRequest, ComputationResponse,
-LangMetaRequest, LangMetaResponse,
-DebugResponse, DebugAsk, GlobalOutputStats};
-
-include!(concat!(env!("OUT_DIR"), "/static.rs"));
-const VERSION_STRING: &'static str = "0.1.0";
-
-pub fn start_repl(langs: Vec<Box<dyn ProgrammingLanguageInterface>>) {
-  let options = command_line_options().parse(std::env::args()).unwrap_or_else(|e| {
-    println!("{:?}", e);
-    exit(1);
-  });
-
-  if options.opt_present("help") {
-    println!("{}", command_line_options().usage("Schala metainterpreter"));
-    exit(0);
-  }
-
-  match options.free[..] {
-    [] | [_] => {
-      let mut repl = repl::Repl::new(langs);
-      repl.run_repl();
-    }
-    [_, ref filename, ..] => {
-      run_noninteractive(filename, langs);
-    }
-  };
-}
-
-fn run_noninteractive(filename: &str, languages: Vec<Box<dyn ProgrammingLanguageInterface>>) {
-  let path = Path::new(filename);
-  let ext = path.extension().and_then(|e| e.to_str()).unwrap_or_else(|| {
-    println!("Source file lacks extension");
-    exit(1);
-  });
-  let mut language = Box::new(languages.into_iter().find(|lang| lang.get_source_file_suffix() == ext)
-    .unwrap_or_else(|| {
-      println!("Extension .{} not recognized", ext);
-      exit(1);
-    }));
-
-  let mut source_file = File::open(path).unwrap();
-  let mut buffer = String::new();
-  source_file.read_to_string(&mut buffer).unwrap();
-
-  let request = ComputationRequest {
-    source: &buffer,
-    debug_requests: HashSet::new(),
-  };
-
-  let response = language.run_computation(request);
-  match response.main_output {
-    Ok(s) => println!("{}", s),
-    Err(s) => println!("{}", s)
-  };
-}
-
-
-fn command_line_options() -> getopts::Options {
-  let mut options = getopts::Options::new();
-  options.optflag("h",
-                  "help",
-                  "Show help text");
-  options.optflag("w",
-                  "webapp",
-                  "Start up web interpreter");
-  options
-}

schala-repl/src/repl/command_tree.rs

@@ -1,99 +0,0 @@
-use super::{Repl, InterpreterDirectiveOutput};
-use crate::repl::directive_actions::DirectiveAction;
-use colored::*;
-
-/// A CommandTree is either a `Terminal` or a `NonTerminal`. When command parsing reaches the first
-/// Terminal, it will use the `DirectiveAction` found there to find an appropriate function to execute,
-/// and then execute it with any remaining arguments
-#[derive(Clone)]
-pub enum CommandTree {
-  Terminal {
-    name: String,
-    children: Vec<CommandTree>,
-    help_msg: Option<String>,
-    action: DirectiveAction,
-  },
-  NonTerminal {
-    name: String,
-    children: Vec<CommandTree>,
-    help_msg: Option<String>,
-    action: DirectiveAction,
-  },
-  Top(Vec<CommandTree>),
-}
-
-impl CommandTree {
-  pub fn nonterm_no_further_tab_completions(s: &str, help: Option<&str>) -> CommandTree {
-    CommandTree::NonTerminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), children: vec![], action: DirectiveAction::Null }
-  }
-
-  pub fn terminal(s: &str, help: Option<&str>, children: Vec<CommandTree>, action: DirectiveAction) -> CommandTree {
-    CommandTree::Terminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), children, action}
-  }
-
-  pub fn nonterm(s: &str, help: Option<&str>, children: Vec<CommandTree>) -> CommandTree {
-    CommandTree::NonTerminal {
-      name: s.to_string(),
-      help_msg: help.map(|x| x.to_string()),
-      children,
-      action: DirectiveAction::Null
-    }
-  }
-
-  pub fn get_cmd(&self) -> &str {
-    match self {
-      CommandTree::Terminal { name, .. } => name.as_str(),
-      CommandTree::NonTerminal {name, ..} => name.as_str(),
-      CommandTree::Top(_) => "",
-    }
-  }
-  pub fn get_help(&self) -> &str {
-    match self {
-      CommandTree::Terminal { help_msg, ..} => help_msg.as_ref().map(|s| s.as_str()).unwrap_or("<no help text provided>"),
-      CommandTree::NonTerminal { help_msg, .. } => help_msg.as_ref().map(|s| s.as_str()).unwrap_or("<no help text provided>"),
-      CommandTree::Top(_) => ""
-    }
-  }
-  pub fn get_children(&self) -> &Vec<CommandTree> {
-    use CommandTree::*;
-    match self {
-      Terminal { children, .. } |
-      NonTerminal { children, .. } |
-      Top(children) => children
-    }
-  }
-  pub fn get_subcommands(&self) -> Vec<&str> {
-    self.get_children().iter().map(|x| x.get_cmd()).collect()
-  }
-
-  pub fn perform(&self, repl: &mut Repl, arguments: &Vec<&str>) -> InterpreterDirectiveOutput {
-    let mut dir_pointer: &CommandTree = self;
-    let mut idx = 0;
-
-    let res: Result<(DirectiveAction, usize), String> = loop {
-      match dir_pointer {
-        CommandTree::Top(subcommands) | CommandTree::NonTerminal { children: subcommands, .. } => {
-          let next_command = match arguments.get(idx) {
-            Some(cmd) => cmd,
-            None => break Err(format!("Command requires arguments"))
-          };
-          idx += 1;
-          match subcommands.iter().find(|sc| sc.get_cmd() == *next_command) {
-            Some(command_tree) => {
-              dir_pointer = command_tree;
-            },
-            None => break Err(format!("Command {} not found", next_command))
-          };
-        },
-        CommandTree::Terminal { action, .. } => {
-          break Ok((action.clone(), idx));
-        },
-      }
-    };
-
-    match res {
-      Ok((action, idx)) => action.perform(repl, &arguments[idx..]),
-      Err(err) => Some(err.red().to_string())
-    }
-  }
-}

schala-repl/src/repl/directive_actions.rs

@@ -1,133 +0,0 @@
-use super::{Repl, InterpreterDirectiveOutput};
-use crate::repl::help::help;
-use crate::language::{LangMetaRequest, LangMetaResponse, DebugAsk, DebugResponse}; 
-use itertools::Itertools;
-use std::fmt::Write as FmtWrite;
-
-#[derive(Debug, Clone)]
-pub enum DirectiveAction {
-  Null,
-  Help,
-  QuitProgram,
-  ListPasses,
-  ShowImmediate,
-  Show,
-  Hide,
-  TotalTimeOff,
-  TotalTimeOn,
-  StageTimeOff,
-  StageTimeOn,
-  Doc,
-}
-
-impl DirectiveAction {
-  pub fn perform(&self, repl: &mut Repl, arguments: &[&str]) -> InterpreterDirectiveOutput {
-    use DirectiveAction::*;
-    match self {
-      Null => None,
-      Help => help(repl, arguments),
-      QuitProgram => {
-        repl.save_before_exit();
-        ::std::process::exit(0)
-      },
-      ListPasses => {
-        let language_state = repl.get_cur_language_state();
-        let pass_names = match language_state.request_meta(LangMetaRequest::StageNames) {
-          LangMetaResponse::StageNames(names) => names,
-          _ => vec![],
-        };
-
-        let mut buf = String::new();
-        for pass in pass_names.iter().map(|name| Some(name)).intersperse(None) {
-          match pass {
-            Some(pass) => write!(buf, "{}", pass).unwrap(),
-            None => write!(buf, " -> ").unwrap(),
-          }
-        }
-        Some(buf)
-      },
-      ShowImmediate => {
-        let cur_state = repl.get_cur_language_state();
-        let stage_name = match arguments.get(0) {
-          Some(s) => s.to_string(),
-          None => return Some(format!("Must specify a thing to debug")),
-        };
-        let meta = LangMetaRequest::ImmediateDebug(DebugAsk::ByStage { stage_name: stage_name.clone(), token: None });
-        let meta_response = cur_state.request_meta(meta);
-
-        let response = match meta_response {
-          LangMetaResponse::ImmediateDebug(DebugResponse { ask, value }) => match  ask {
-            DebugAsk::ByStage { stage_name: ref this_stage_name, ..} if *this_stage_name == stage_name => value,
-            _ => return Some(format!("Wrong debug stage"))
-          },
-          _ => return Some(format!("Invalid language meta response")),
-        };
-        Some(response)
-      },
-      Show => {
-        let this_stage_name = match arguments.get(0) {
-          Some(s) => s.to_string(),
-          None => return Some(format!("Must specify a stage to show")),
-        };
-        let token = arguments.get(1).map(|s| s.to_string());
-        repl.options.debug_asks.retain(|ask| match ask {
-          DebugAsk::ByStage { stage_name, .. } if *stage_name == this_stage_name => false,
-          _ => true
-        });
-
-        let ask = DebugAsk::ByStage { stage_name: this_stage_name, token };
-        repl.options.debug_asks.insert(ask);
-        None
-      },
-      Hide => {
-        let stage_name_to_remove = match arguments.get(0) {
-          Some(s) => s.to_string(),
-          None => return Some(format!("Must specify a stage to hide")),
-        };
-        repl.options.debug_asks.retain(|ask| match ask {
-          DebugAsk::ByStage { stage_name, .. } if *stage_name == stage_name_to_remove => false,
-          _ => true
-        });
-        None
-      },
-      TotalTimeOff => total_time_off(repl, arguments),
-      TotalTimeOn => total_time_on(repl, arguments),
-      StageTimeOff => stage_time_off(repl, arguments),
-      StageTimeOn => stage_time_on(repl, arguments),
-      Doc => doc(repl, arguments),
-    }
-  }
-}
-
-fn total_time_on(repl: &mut Repl, _: &[&str]) -> InterpreterDirectiveOutput {
-  repl.options.show_total_time = true;
-  None
-}
-
-fn total_time_off(repl: &mut Repl, _: &[&str]) -> InterpreterDirectiveOutput {
-  repl.options.show_total_time = false;
-  None
-}
-
-fn stage_time_on(repl: &mut Repl, _: &[&str]) -> InterpreterDirectiveOutput {
-  repl.options.show_stage_times = true;
-  None
-}
-
-fn stage_time_off(repl: &mut Repl, _: &[&str]) -> InterpreterDirectiveOutput {
-  repl.options.show_stage_times = false;
-  None
-}
-
-fn doc(repl: &mut Repl, arguments: &[&str]) -> InterpreterDirectiveOutput {
-  arguments.get(0).map(|cmd| {
-    let source = cmd.to_string();
-    let meta = LangMetaRequest::Docs { source };
-    let cur_state = repl.get_cur_language_state();
-    match cur_state.request_meta(meta) {
-      LangMetaResponse::Docs { doc_string } => Some(doc_string),
-      _ => Some(format!("Invalid doc response"))
-    }
-  }).unwrap_or(Some(format!(":docs needs an argument")))
-}
-

schala-repl/src/repl/directives.rs

@@ -1,55 +0,0 @@
-use crate::repl::command_tree::CommandTree;
-use crate::repl::directive_actions::DirectiveAction;
-
-pub fn directives_from_pass_names(pass_names: &Vec<String>) -> CommandTree {
-  let passes_directives: Vec<CommandTree> = pass_names.iter()
-    .map(|pass_name| {
-      if pass_name == "parsing" {
-        CommandTree::nonterm(pass_name, None, vec![
-          CommandTree::nonterm_no_further_tab_completions("compact", None),
-          CommandTree::nonterm_no_further_tab_completions("expanded", None),
-          CommandTree::nonterm_no_further_tab_completions("trace", None),
-        ])
-      } else {
-        CommandTree::nonterm_no_further_tab_completions(pass_name, None) 
-      }
-    })
-    .collect();
-  CommandTree::Top(get_list(&passes_directives, true))
-}
-
-fn get_list(passes_directives: &Vec<CommandTree>, include_help: bool) -> Vec<CommandTree> {
-  use DirectiveAction::*;
-
-  vec![
-    CommandTree::terminal("exit", Some("exit the REPL"), vec![], QuitProgram),
-    CommandTree::terminal("quit", Some("exit the REPL"), vec![], QuitProgram),
-    CommandTree::terminal("help", Some("Print this help message"), if include_help { get_list(passes_directives, false) } else { vec![] }, Help),
-    CommandTree::nonterm("debug",
-      Some("Configure debug information"),
-      vec![
-        CommandTree::terminal("list-passes", Some("List all registered compiler passes"), vec![], ListPasses),
-        CommandTree::terminal("show-immediate", None, passes_directives.clone(), ShowImmediate),
-        CommandTree::terminal("show", Some("Show debug output for a specific pass"), passes_directives.clone(), Show),
-        CommandTree::terminal("hide", Some("Hide debug output for a specific pass"), passes_directives.clone(), Hide),
-        CommandTree::nonterm("total-time", None, vec![
-          CommandTree::terminal("on", None, vec![], TotalTimeOn), 
-          CommandTree::terminal("off", None, vec![], TotalTimeOff),
-        ]),
-        CommandTree::nonterm("stage-times", Some("Computation time per-stage"), vec![
-          CommandTree::terminal("on", None, vec![], StageTimeOn),
-          CommandTree::terminal("off", None, vec![], StageTimeOff),
-        ])
-      ]
-    ),
-    CommandTree::nonterm("lang",
-      Some("switch between languages, or go directly to a langauge by name"),
-      vec![
-        CommandTree::nonterm_no_further_tab_completions("next", None),
-        CommandTree::nonterm_no_further_tab_completions("prev", None),
-        CommandTree::nonterm("go", None, vec![]),
-      ]
-    ),
-    CommandTree::terminal("doc", Some("Get language-specific help for an item"), vec![], Doc),
-  ]
-}

schala-repl/src/repl/help.rs

@@ -1,59 +0,0 @@
-use std::fmt::Write as FmtWrite;
-
-use colored::*;
-use super::command_tree::CommandTree;
-use super::{Repl, InterpreterDirectiveOutput};
-
-pub fn help(repl: &mut Repl, arguments: &[&str]) -> InterpreterDirectiveOutput {
-  match arguments {
-    [] =>  return global_help(repl),
-    commands => {
-      let dirs = repl.get_directives();
-      Some(match get_directive_from_commands(commands, &dirs) {
-        None => format!("Directive `{}` not found", commands.last().unwrap()),
-        Some(dir) => {
-          let mut buf = String::new();
-          let cmd = dir.get_cmd();
-          let children = dir.get_children();
-          writeln!(buf, "`{}` - {}", cmd, dir.get_help()).unwrap();
-          for sub in children.iter() {
-            writeln!(buf, "\t`{} {}` - {}", cmd, sub.get_cmd(), sub.get_help()).unwrap();
-          }
-          buf
-        }
-      })
-    }
-  }
-}
-
-fn get_directive_from_commands<'a>(commands: &[&str], dirs: &'a CommandTree) -> Option<&'a CommandTree> {
-  let mut directive_list = dirs.get_children();
-  let mut matched_directive = None;
-  for cmd in commands {
-    let found = directive_list.iter().find(|directive| directive.get_cmd() == *cmd);
-    if let Some(dir) = found {
-      directive_list = dir.get_children();
-    }
-
-    matched_directive = found;
-  }
-  matched_directive
-}
-
-fn global_help(repl: &mut Repl) -> InterpreterDirectiveOutput {
-  let mut buf = String::new();
-  let sigil = repl.interpreter_directive_sigil;
-
-  writeln!(buf, "{} version {}", "Schala REPL".bright_red().bold(), crate::VERSION_STRING).unwrap();
-  writeln!(buf, "-----------------------").unwrap();
-
-  for directive in repl.get_directives().get_children() {
-    writeln!(buf, "{}{} - {}", sigil, directive.get_cmd(), directive.get_help()).unwrap();
-  }
-
-  let ref lang = repl.get_cur_language_state();
-  writeln!(buf, "").unwrap();
-  writeln!(buf, "Language-specific help for {}", lang.get_language_name()).unwrap();
-  writeln!(buf, "-----------------------").unwrap();
-  Some(buf)
-}

schala-repl/src/repl/mod.rs

@@ -1,251 +0,0 @@
-use std::sync::Arc;
-use std::collections::HashSet;
-
-use crate::language::{ProgrammingLanguageInterface,
-ComputationRequest, LangMetaResponse, LangMetaRequest};
-
-mod command_tree;
-use self::command_tree::CommandTree;
-mod repl_options;
-use repl_options::ReplOptions;
-mod directive_actions;
-mod directives;
-use directives::directives_from_pass_names;
-mod help;
-mod response;
-use response::ReplResponse;
-
-const HISTORY_SAVE_FILE: &'static str = ".schala_history";
-const OPTIONS_SAVE_FILE: &'static str = ".schala_repl";
-
-type InterpreterDirectiveOutput = Option<String>;
-
-pub struct Repl {
-  pub interpreter_directive_sigil: char,
-  line_reader: ::linefeed::interface::Interface<::linefeed::terminal::DefaultTerminal>,
-  language_states: Vec<Box<dyn ProgrammingLanguageInterface>>,
-  options: ReplOptions,
-}
-
-#[derive(Clone)]
-enum PromptStyle {
-  Normal,
-  Multiline
-}
-
-impl Repl {
-  pub fn new(initial_states: Vec<Box<dyn ProgrammingLanguageInterface>>) -> Repl {
-    use linefeed::Interface;
-    let line_reader = Interface::new("schala-repl").unwrap();
-    let interpreter_directive_sigil = ':';
-
-    Repl {
-      interpreter_directive_sigil,
-      line_reader,
-      language_states: initial_states,
-      options: ReplOptions::new(),
-    }
-  }
-
-  pub fn run_repl(&mut self) {
-    println!("Schala MetaInterpreter version {}", crate::VERSION_STRING);
-    println!("Type {}help for help with the REPL", self.interpreter_directive_sigil);
-    self.load_options();
-    self.handle_repl_loop();
-    self.save_before_exit();
-    println!("Exiting...");
-  }
-
-  fn load_options(&mut self) {
-    self.line_reader.load_history(HISTORY_SAVE_FILE).unwrap_or(());
-    match ReplOptions::load_from_file(OPTIONS_SAVE_FILE) {
-      Ok(options) => {
-        self.options = options;
-      },
-      Err(()) => ()
-    };
-  }
-
-  fn handle_repl_loop(&mut self) {
-    use linefeed::ReadResult::*;
-    let sigil = self.interpreter_directive_sigil;
-
-    'main: loop {
-      macro_rules! match_or_break {
-        ($line:expr) => {
-          match $line {
-            Err(e) => {
-              println!("readline IO Error: {}", e);
-              break 'main;
-            },
-            Ok(Eof) | Ok(Signal(_)) => break 'main,
-            Ok(Input(ref input)) => input,
-          }
-        }
-      }
-      self.update_line_reader();
-      let line = self.line_reader.read_line();
-      let input: &str = match_or_break!(line);
-
-      self.line_reader.add_history_unique(input.to_string());
-      let mut chars = input.chars().peekable();
-      let repl_responses = match chars.nth(0) {
-        Some(ch) if ch == sigil => {
-          if chars.peek() == Some(&'{') {
-            let mut buf = String::new();
-            buf.push_str(input.get(2..).unwrap());
-            'multiline: loop {
-              self.set_prompt(PromptStyle::Multiline);
-              let new_line = self.line_reader.read_line();
-              let new_input = match_or_break!(new_line);
-              if new_input.starts_with(":}") {
-                break 'multiline;
-              } else {
-                buf.push_str(new_input);
-                buf.push_str("\n");
-              }
-            }
-            self.handle_input(&buf)
-          } else {
-            match self.handle_interpreter_directive(input) {
-              Some(directive_output) => println!("<> {}", directive_output),
-              None => (),
-            }
-            continue
-          }
-        },
-        _ => self.handle_input(input)
-      };
-
-      for repl_response in repl_responses.iter() {
-        println!("{}", repl_response);
-      }
-    }
-  }
-
-  fn update_line_reader(&mut self) {
-    let tab_complete_handler = TabCompleteHandler::new(self.interpreter_directive_sigil, self.get_directives());
-    self.line_reader.set_completer(Arc::new(tab_complete_handler)); //TODO fix this here
-    self.set_prompt(PromptStyle::Normal);
-  }
-
-  fn set_prompt(&mut self, prompt_style: PromptStyle) {
-    let prompt_str = match prompt_style {
-      PromptStyle::Normal => ">> ".to_string(),
-      PromptStyle::Multiline => ">| ".to_string(),
-    };
-
-    self.line_reader.set_prompt(&prompt_str).unwrap();
-  }
-
-  fn save_before_exit(&self) {
-    self.line_reader.save_history(HISTORY_SAVE_FILE).unwrap_or(());
-    self.options.save_to_file(OPTIONS_SAVE_FILE);
-  }
-
-  fn handle_interpreter_directive(&mut self, input: &str) -> InterpreterDirectiveOutput {
-    let mut iter = input.chars();
-    iter.next();
-    let arguments: Vec<&str> = iter
-      .as_str()
-      .split_whitespace()
-      .collect();
-
-    if arguments.len() < 1 {
-      return None;
-    }
-
-    let directives = self.get_directives();
-    directives.perform(self, &arguments)
-  }
-
-  fn get_cur_language_state(&mut self) -> &mut Box<dyn ProgrammingLanguageInterface> {
-    //TODO this is obviously not complete
-    &mut self.language_states[0]
-  }
-
-  fn handle_input(&mut self, input: &str) -> Vec<ReplResponse> {
-    let mut debug_requests = HashSet::new();
-    for ask in self.options.debug_asks.iter() {
-      debug_requests.insert(ask.clone());
-    }
-
-    let request = ComputationRequest { source: input, debug_requests };
-    let ref mut language_state = self.get_cur_language_state();
-    let response = language_state.run_computation(request);
-    response::handle_computation_response(response, &self.options)
-  }
-
-  fn get_directives(&mut self) -> CommandTree {
-    let language_state = self.get_cur_language_state();
-    let pass_names = match language_state.request_meta(LangMetaRequest::StageNames) {
-      LangMetaResponse::StageNames(names) => names,
-      _ => vec![],
-    };
-
-    directives_from_pass_names(&pass_names)
-  }
-}
-
-
-struct TabCompleteHandler {
-  sigil: char,
-  top_level_commands: CommandTree,
-}
-
-use linefeed::complete::{Completion, Completer};
-use linefeed::terminal::Terminal;
-
-impl TabCompleteHandler {
-  fn new(sigil: char, top_level_commands: CommandTree) -> TabCompleteHandler {
-    TabCompleteHandler {
-      top_level_commands,
-      sigil,
-    }
-  }
-}
-
-impl<T: Terminal> Completer<T> for TabCompleteHandler {
-  fn complete(&self, word: &str, prompter: &::linefeed::prompter::Prompter<T>, start: usize, _end: usize) -> Option<Vec<Completion>> {
-    let line = prompter.buffer();
-
-    if !line.starts_with(self.sigil) {
-      return None;
-    }
-
-    let mut words = line[1..(if start == 0 { 1 } else { start })].split_whitespace();
-    let mut completions = Vec::new();
-    let mut command_tree: Option<&CommandTree> = Some(&self.top_level_commands);
-
-    loop {
-      match words.next() {
-        None => {
-          let top = match command_tree {
-            Some(CommandTree::Top(_)) => true,
-            _ => false
-          };
-          let word = if top { word.get(1..).unwrap() } else { word };
-          for cmd in command_tree.map(|x| x.get_subcommands()).unwrap_or(vec![]).into_iter() {
-            if cmd.starts_with(word) {
-              completions.push(Completion {
-                completion: format!("{}{}", if top { ":" } else { "" }, cmd),
-                display: Some(cmd.to_string()),
-                suffix: ::linefeed::complete::Suffix::Some(' ')
-              })
-            }
-          }
-          break;
-        },
-        Some(s) => {
-          let new_ptr: Option<&CommandTree> = command_tree.and_then(|cm| match cm {
-            CommandTree::Top(children) => children.iter().find(|c| c.get_cmd() == s),
-            CommandTree::NonTerminal { children, .. } => children.iter().find(|c| c.get_cmd() == s),
-            CommandTree::Terminal { children, .. } => children.iter().find(|c| c.get_cmd() == s),
-          });
-          command_tree = new_ptr;
-        }
-      }
-    }
-    Some(completions)
-  }
-}

schala-repl/src/repl/repl_options.rs

@@ -1,47 +0,0 @@
-use crate::language::DebugAsk;
-
-use std::io::{Read, Write};
-use std::collections::HashSet;
-use std::fs::File;
-
-#[derive(Serialize, Deserialize)]
-pub struct ReplOptions {
-  pub debug_asks: HashSet<DebugAsk>,
-  pub show_total_time: bool,
-  pub show_stage_times: bool,
-}
-
-impl ReplOptions {
-  pub fn new() -> ReplOptions {
-    ReplOptions {
-      debug_asks: HashSet::new(),
-      show_total_time: true,
-      show_stage_times: false,
-    }
-  }
-
-  pub fn save_to_file(&self, filename: &str) {
-    let res = File::create(filename)
-      .and_then(|mut file| {
-        let buf = crate::serde_json::to_string(self).unwrap();
-        file.write_all(buf.as_bytes())
-      });
-    if let Err(err) = res {
-      println!("Error saving {} file {}", filename, err);
-    }
-  }
-
-  pub fn load_from_file(filename: &str) -> Result<ReplOptions, ()> {
-    File::open(filename)
-      .and_then(|mut file| {
-        let mut contents = String::new();
-        file.read_to_string(&mut contents)?;
-        Ok(contents)
-      })
-    .and_then(|contents| {
-      let output: ReplOptions = crate::serde_json::from_str(&contents)?;
-      Ok(output)
-    })
-    .map_err(|_| ())
-  }
-}

schala-repl/src/repl/response.rs

@@ -1,67 +0,0 @@
-use colored::*;
-use std::fmt;
-use std::fmt::Write;
-
-use super::ReplOptions;
-use crate::language::{ DebugAsk, ComputationResponse};
-
-pub struct ReplResponse {
-  label: Option<String>,
-  text: String,
-  color: Option<Color>
-}
-
-impl fmt::Display for ReplResponse {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    let mut buf = String::new();
-    if let Some(ref label) = self.label {
-      write!(buf, "({})", label).unwrap();
-    }
-    write!(buf, "=> {}", self.text).unwrap();
-    write!(f, "{}", match self.color {
-      Some(c) => buf.color(c),
-      None => buf.normal()
-    })
-  }
-}
-
-
-pub fn handle_computation_response(response: ComputationResponse, options: &ReplOptions) -> Vec<ReplResponse> {
-  let mut responses = vec![];
-
-  if options.show_total_time {
-    responses.push(ReplResponse {
-      label: Some("Total time".to_string()),
-      text: format!("{:?}", response.global_output_stats.total_duration),
-      color: None,
-    });
-  }
-
-  if options.show_stage_times {
-    responses.push(ReplResponse {
-      label: Some("Stage times".to_string()),
-      text: format!("{:?}", response.global_output_stats.stage_durations),
-      color: None,
-    });
-  }
-
-  for debug_resp in response.debug_responses {
-    let stage_name = match debug_resp.ask {
-      DebugAsk::ByStage { stage_name, .. } => stage_name,
-      _ => continue,
-    };
-    responses.push(ReplResponse {
-      label: Some(stage_name.to_string()),
-      text: debug_resp.value,
-      color: Some(Color::Red),
-    });
-  }
-
-  responses.push(match response.main_output {
-    Ok(s) => ReplResponse { label: None, text: s, color: None },
-    Err(e) => ReplResponse { label: Some("Error".to_string()), text: e, color: Some(Color::Red) },
-  });
-
-  responses
-}
-

source_files/closure.maaru

@@ -1,11 +0,0 @@
-
-
-fn outer() {
-    fn inner(a) {
-        a + 10
-    }
-
-    inner(20) + 8.3
-}
-
-outer()

source_files/compile.maaru

@@ -1,21 +0,0 @@
-
-fn hella(a, b) {
-    a + b
-}
-
-fn paha(x, y, z) {
-    x * y * z
-}
-
-a = 1
-
-c = if a {
-    10
-} else {
-    20
-}
-
-q = 4
-q = q + 2
-q + 1 + c
-

source_files/conditional.maaru

@@ -1,8 +0,0 @@
-if 20 {
-    a = 20
-    b = 30
-    c = 40
-    a + b + c
-} else  {
-    Null
-}

source_files/lambda.maaru

@@ -1,5 +0,0 @@
-
-(fn(q) { q * 2 }(25))
-
-a = fn(x) { x + 5 }
-a(2)

source_files/main.maaru

@@ -1,17 +0,0 @@
-
-fn add(a, b) {
-   a + b
-}
-
-fn subtract(a, b) {
-    a - b
-}
-
-fn main() {
-    first_value = add(20, 20)
-    second_value = subtract(700, 650)
-    first_value + second_value
-}
-
-main()
-

source_files/recurse.maaru

@@ -1,24 +0,0 @@
-
-
-fn hella(x) {
-    print("hey")
-    if x == 3 {
-        Null
-    } else {
-        hella(x + 1)
-    }
-}
-
-hella(0)
-        
-
-
-fn fib(x) {
-    if x < 3 {
-      1
-    } else {
-      fib(x - 1) + fib(x - 2)
-    }
-}
-
-fib(10)

source_files/schala/does_scope_work.schala

@@ -1,11 +0,0 @@
-let c = 10
-
-fn add(a, b) {
-  let c = a + b
-  c
-}
-
-let mut b = 20
-
-println(add(1,2))
-println(c + b)

source_files/schala/first_program.schala

@@ -1,17 +0,0 @@
-fn main() {
-  let a = 10
-  let b = 20
-  a + b
-}
-
-//this is a one-line comment
-
-/* this is
-a multiline
-comment
-*/
-
-print(main())
-
-
-

source_files/schala/fizzbuzz.schala

@@ -1,12 +0,0 @@
-
-for n <- 1..=100 {
-  if n % 15 == 0 {
-    print("FizzBuzz")
-  } else if n % 5 == 0 {
-    print("Buzz")
-  } else if n % 3 == 0 {
-    print("Fizz")
-  } else {
-    print(n.to_string())
-  }
-}

source_files/schala/syntax_playground.schala

@@ -1,114 +0,0 @@
-
-fn main() {
-
-//comments are C-style
-/* nested comments /* are cool */ */
-
-}
-
-@annotations are with @-
-
-// variable expressions
-  var a: I32 = 20
-  const b: String = 20
-
-  there(); can(); be(); multiple(); statements(); per_line();
-
-  //string interpolation
-  const yolo = "I have ${a + b} people in my house"
-
-  // let expressions ??? not sure if I want this
-  let a = 10, b = 20, c = 30 in a + b + c
-
-  //list literal
-  const q = [1,2,3,4]
-
-  //lambda literal 
-  q.map({|item| item * 100 })
-
-  fn yolo(a: MyType, b: YourType): ReturnType<Param1, Param2> {
-    if a == 20 {
-      return "early"
-    }
-    var sex = 20
-    sex
-  }
-
-
-/* for/while loop topics */
-
-   //infinite loop
-   while {
-     if x() { break }
-     ...
-   }
-
-
-   //conditional loop
-   while conditionHolds() {
-      ...
-   }
-
-
-  //iteration over a variable
-  for i <- [1..1000]  {
-
-  } //return type is return type of block
-
-
-  //monadic decomposition
-  for {
-    a <- maybeInt();
-    s <- foo() 
-  } return {
-    a + s
-  } //return type is Monad<return type of block>
-
-/* end of for loops */
-
-
-
-/* conditionals/pattern matching */
-
-// "is" operator for "does this pattern match"
-
-x is Some(t) // type bool
-
-if x {
-  is Some(t) => {
-  },
-  is None => {
-
-  }
-}
-
-
- //syntax is, I guess, for <expr> <brace-block>, where <expr> is a bool, or a <arrow-expr>
-
- // type level alises
- typealias <name> = <other type> #maybe thsi should be 'alias'?
-
-/*
-what if type A = B meant that you could had to create A's with A(B), but when you used A's the interface was exactly like B's?
- maybe introduce a 'newtype' keyword for this
- */
-
- //declaring types of all stripes
- type MyData = { a: i32, b: String }
- type MyType = MyType
- type Option<a> = None | Some(a)
- type Signal = Absence | SimplePresence(i32) | ComplexPresence {a: i32, b: MyCustomData}
-
- //traits
- 
- trait Bashable { }
- trait Luggable {
-  fn lug(self, a: Option<Self>)
- }
-
-}
-
-
-// lambdas
-// ruby-style not rust-style
-const a: X -> Y -> Z = {|x,y|  }

source_files/schala/test.schala

@@ -1,17 +0,0 @@
-
-println(sua(4))
-
-fn sua(x): Int {
-  x + 10
-}
-
-
-//let a = getline()
-
-/*
-if a == "true" {
-  println("You typed true")
-} else {
-  println("You typed something else")
-}
-*/

source_files/test.maaru

@@ -1,12 +0,0 @@
-
-fn a(x) {
-    x + 20
-}
-
-fn x(x) {
-    x + a(9384)
-}
-
-a(0)
-x(1)
-

source_files/test.rukka

@@ -1,3 +0,0 @@
-
-(display (+ 1 2))
-(display "Hello")

source_files/unicode.maaru

@@ -1,8 +0,0 @@
-
-fn めんどくさい(a) {
-    a + 20
-}
-
-print(めんどくさい(394))
-
-

source_files/while.maaru

@@ -1,7 +0,0 @@
-
-
-a = 0
-while a < 100000
-  print("hello", a)
-  a = a + 1
-end

src/main.rs

@@ -1,15 +0,0 @@
-extern crate schala_repl;
-
-//extern crate maaru_lang;
-//extern crate rukka_lang;
-//extern crate robo_lang;
-extern crate schala_lang;
-use schala_repl::{ProgrammingLanguageInterface, start_repl};
-
-extern { }
-
-fn main() {
-  let langs: Vec<Box<dyn ProgrammingLanguageInterface>> = vec![Box::new(schala_lang::Schala::new())];
-  start_repl(langs);
-}
-

static/index.html

@@ -1,17 +0,0 @@
-<!DOCTYPE html>
-<html>
-  <head>
-    <title>Schala Metainterpreter Web Evaluator</title>
-    <style>
-      .CodeArea {
-        display: flex;
-        flex-direction: row;
-      }
-    </style>
-  </head>
-  <body>
-    <div id="main">
-    </div>
-    <script src="bundle.js"></script>
-  </body>
-</html>

static/main.jsx

@@ -1,64 +0,0 @@
-const React = require("react");
-const ReactDOM = require("react-dom");
-const superagent = require("superagent");
-
-const serverAddress = "http://localhost:8000";
-
-class CodeArea extends React.Component {
-  constructor(props) {
-    super(props);
-    this.state = {value: "", lastOutput: null};
-    this.handleChange = this.handleChange.bind(this);
-    this.submit = this.submit.bind(this);
-  }
-
-  handleChange(event) {
-    this.setState({value: event.target.value});
-  }
-
-  submit(event) {
-    console.log("Event", this.state.value);
-    const source = this.state.value;
-
-    superagent.post(`${serverAddress}/input`)
-      .send({ source })
-      .set("accept", "json")
-      .end((error, response) => {
-        if (response) {
-          console.log("Resp", response);
-          this.setState({lastOutput: response.body.text})
-        } else {
-          console.error("Error: ", error);
-        }
-      });
-  }
-
-  renderOutput() {
-    if (!this.state.lastOutput) {
-      return null;
-    }
-    return <textarea readOnly value={ this.state.lastOutput } />;
-  }
-
-  render() {
-    return (<div className="CodeArea">
-      <div className="input">
-        <textarea value={ this.state.value } onChange={this.handleChange}>
-        </textarea>
-        <button onClick={ this.submit }>Run!</button>
-      </div>
-      <div className="output">
-        { this.renderOutput() }
-      </div>
-    </div>);
-  }
-}
-
-const main = (<div>
-  <h1>Schala web input</h1>
-  <p>Write your source code here</p>
-  <CodeArea/>
-</div>);
-
-const rootDom = document.getElementById("main");
-ReactDOM.render(main, rootDom);

static/package.json

@@ -1,27 +0,0 @@
-{
-  "name": "static",
-  "version": "1.0.0",
-  "main": "index.js",
-  "license": "MIT",
-  "dependencies": {
-    "babel": "^6.23.0",
-    "babel-preset-es2015": "^6.24.1",
-    "babel-preset-react": "^6.24.1",
-    "babelify": "^7.3.0",
-    "browserify": "^14.4.0",
-    "react": "^15.6.1",
-    "react-dom": "^15.6.1",
-    "superagent": "^3.6.3",
-    "uglify-js": "^3.1.1"
-  },
-  "babel": {
-    "presets": [
-      "babel-preset-react",
-      "babel-preset-es2015"
-    ]
-  },
-  "scripts": {
-    "build": "browserify main.jsx -t babelify -o bundle.js",
-    "build-minify": "browserify main.jsx -t babelify | uglifyjs > bundle.js"
-  }
-}

subtrees/parser-combinator/.gitignore

@@ -0,0 +1,2 @@
+/target
+/Cargo.lock

subtrees/parser-combinator/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "parser-combinator"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+arbitrary = "1.2.0"
+proptest = "1.0.0"
+
+[dev-dependencies]
+rstest = "0.16.0"

subtrees/parser-combinator/README.md

@@ -0,0 +1,10 @@
+# Rust Parser Combinator
+
+This is a super-basic Rust parser combinator library I wrote mostly
+as an exercise for myself. Inspired by [nom](https://github.com/rust-bakery/nom)
+and [chumsky](https://github.com/zesterer/chumsky)
+
+## Ideas for future work
+
+* See if some of the ideas in [Efficient Parsing with Parser Combinators](https://research.rug.nl/en/publications/efficient-parsing-with-parser-combinators)
+can be incorporated here.

subtrees/parser-combinator/src/choice/mod.rs

@@ -0,0 +1,198 @@
+use crate::parser::{ParseResult, Parser, ParserInput, Representation};
+
+pub fn choice2<P1, P2, I, O, E>(parser1: P1, parser2: P2) -> impl Parser<I, O, E>
+where
+    P1: Parser<I, O, E>,
+    P2: Parser<I, O, E>,
+    I: ParserInput + Clone,
+{
+    choice((parser1, parser2))
+}
+
+pub fn choice<C, I, O, E>(choices: C) -> impl Parser<I, O, E>
+where
+    C: Choice<I, O, E>,
+    I: ParserInput + Clone,
+{
+    let rep = choices.representation();
+    (move |input| choices.parse(input), rep)
+}
+
+pub trait Choice<I: Clone, O, E> {
+    fn parse(&self, input: I) -> ParseResult<I, O, E>;
+    fn representation(&self) -> Representation;
+}
+
+impl<I, O, E, P1, P2> Choice<I, O, E> for (P1, P2)
+where
+    P1: Parser<I, O, E>,
+    P2: Parser<I, O, E>,
+    I: ParserInput + Clone,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        let parsers = vec![&self.0 as &dyn Parser<I, O, E>, &self.1];
+        choice_loop(input, parsers)
+    }
+
+    fn representation(&self) -> Representation {
+        let parsers = vec![&self.0 as &dyn Parser<I, O, E>, &self.1];
+        repr_loop(parsers)
+    }
+}
+
+impl<I, O, E, P1, P2, P3> Choice<I, O, E> for (P1, P2, P3)
+where
+    P1: Parser<I, O, E>,
+    P2: Parser<I, O, E>,
+    P3: Parser<I, O, E>,
+    I: ParserInput + Clone,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        let parsers = vec![&self.0 as &dyn Parser<I, O, E>, &self.1, &self.2];
+        choice_loop(input, parsers)
+    }
+
+    fn representation(&self) -> Representation {
+        let parsers = vec![&self.0 as &dyn Parser<I, O, E>, &self.1, &self.2];
+        repr_loop(parsers)
+    }
+}
+
+impl<I, O, E, P1, P2, P3, P4> Choice<I, O, E> for (P1, P2, P3, P4)
+where
+    P1: Parser<I, O, E>,
+    P2: Parser<I, O, E>,
+    P3: Parser<I, O, E>,
+    P4: Parser<I, O, E>,
+    I: ParserInput + Clone,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        let parsers = vec![&self.0 as &dyn Parser<I, O, E>, &self.1, &self.2, &self.3];
+        choice_loop(input, parsers)
+    }
+
+    fn representation(&self) -> Representation {
+        let parsers = vec![&self.0 as &dyn Parser<I, O, E>, &self.1, &self.2, &self.3];
+        repr_loop(parsers)
+    }
+}
+
+impl<I, O, E, P1, P2, P3, P4, P5> Choice<I, O, E> for (P1, P2, P3, P4, P5)
+where
+    P1: Parser<I, O, E>,
+    P2: Parser<I, O, E>,
+    P3: Parser<I, O, E>,
+    P4: Parser<I, O, E>,
+    P5: Parser<I, O, E>,
+    I: ParserInput + Clone,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        let parsers = vec![
+            &self.0 as &dyn Parser<I, O, E>,
+            &self.1,
+            &self.2,
+            &self.3,
+            &self.4,
+        ];
+        choice_loop(input, parsers)
+    }
+
+    fn representation(&self) -> Representation {
+        let parsers = vec![
+            &self.0 as &dyn Parser<I, O, E>,
+            &self.1,
+            &self.2,
+            &self.3,
+            &self.4,
+        ];
+        repr_loop(parsers)
+    }
+}
+
+impl<I, O, E, P1, P2, P3, P4, P5, P6> Choice<I, O, E> for (P1, P2, P3, P4, P5, P6)
+where
+    P1: Parser<I, O, E>,
+    P2: Parser<I, O, E>,
+    P3: Parser<I, O, E>,
+    P4: Parser<I, O, E>,
+    P5: Parser<I, O, E>,
+    P6: Parser<I, O, E>,
+    I: ParserInput + Clone,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        let parsers = vec![
+            &self.0 as &dyn Parser<I, O, E>,
+            &self.1,
+            &self.2,
+            &self.3,
+            &self.4,
+            &self.5,
+        ];
+        choice_loop(input, parsers)
+    }
+    fn representation(&self) -> Representation {
+        let parsers = vec![
+            &self.0 as &dyn Parser<I, O, E>,
+            &self.1,
+            &self.2,
+            &self.3,
+            &self.4,
+            &self.5,
+        ];
+        repr_loop(parsers)
+    }
+}
+
+fn choice_loop<I, O, E>(input: I, parsers: Vec<&dyn Parser<I, O, E>>) -> ParseResult<I, O, E>
+where
+    I: ParserInput + Clone,
+{
+    //TODO need a more principled way to return an error when no choices work
+    let mut err = None;
+
+    for parser in parsers.iter() {
+        match parser.parse(input.clone()) {
+            Ok(result) => return Ok(result),
+            Err(e) => {
+                err = Some(e);
+            }
+        }
+    }
+    Err(err.unwrap())
+}
+
+fn repr_loop<I, O, E>(parsers: Vec<&dyn Parser<I, O, E>>) -> Representation
+where
+    I: ParserInput + Clone,
+{
+    let mut iter = parsers.iter().map(|p| p.representation());
+    Representation::from_choice(&mut iter)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::combinators::repeated;
+    use crate::primitives::literal;
+
+    #[test]
+    fn test_choice() {
+        let p = choice2(
+            literal("gnostika").to(1),
+            repeated(literal(" ")).at_least(1).to(2),
+        );
+        assert_eq!(p.parse("gnostika twentynine"), Ok((1, " twentynine")));
+    }
+
+    #[test]
+    fn test_several_choices() {
+        let p = choice((
+            literal("a").to(1),
+            literal("q").to(10),
+            repeated(literal("chutney")).to(200),
+            literal("banana").to(10000),
+        ));
+
+        assert_eq!(p.parse("q drugs").unwrap(), (10, " drugs"));
+    }
+}

subtrees/parser-combinator/src/combinators/map.rs

@@ -0,0 +1,16 @@
+use crate::parser::{Parser, ParserInput};
+
+pub fn map<P, F, I, O1, O2, E>(parser: P, map_fn: F) -> impl Parser<I, O2, E>
+where
+    I: ParserInput,
+    P: Parser<I, O1, E>,
+    F: Fn(O1) -> O2,
+{
+    let rep = parser.representation();
+    let p = move |input| {
+        parser
+            .parse(input)
+            .map(|(result, rest)| (map_fn(result), rest))
+    };
+    (p, rep)
+}

subtrees/parser-combinator/src/combinators/mod.rs

@@ -0,0 +1,66 @@
+mod map;
+mod optional;
+mod repeated;
+mod separated_by;
+
+pub use map::map;
+pub use optional::optional;
+pub use repeated::repeated;
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::parser::Parser;
+    use crate::primitives::literal;
+
+    #[test]
+    fn test_map() {
+        let lit_a = literal("a");
+        let output = lit_a.map(|s| s.to_uppercase()).parse("a yolo");
+        assert_eq!(output.unwrap(), ("A".to_string(), " yolo"));
+    }
+
+    #[test]
+    fn test_one_or_more() {
+        let p = repeated(literal("bongo ")).at_least(1);
+        let input = "bongo bongo bongo bongo bongo ";
+
+        let (output, rest) = p.parse(input).unwrap();
+        assert_eq!(rest, "");
+        assert_eq!(output.len(), 5);
+
+        let (output, rest) = p.parse("bongo ecks").unwrap();
+        assert_eq!(output.len(), 1);
+        assert_eq!(rest, "ecks");
+    }
+
+    #[test]
+    fn test_separated_by() {
+        let p = repeated(literal("garb").to(20))
+            .separated_by(repeated(literal(" ")).at_least(1), false);
+
+        assert_eq!(
+            p.parse("garb garb      garb     garb").unwrap(),
+            (vec![20, 20, 20, 20], "")
+        );
+
+        assert!(p.parse("garb garb      garb     garb ").is_err());
+
+        let p =
+            repeated(literal("garb").to(20)).separated_by(repeated(literal(" ")).at_least(1), true);
+
+        assert_eq!(
+            p.parse("garb garb      garb     garb").unwrap(),
+            (vec![20, 20, 20, 20], "")
+        );
+
+        assert_eq!(
+            p.parse("garb garb      garb     garb     ").unwrap(),
+            (vec![20, 20, 20, 20], "")
+        );
+        assert_eq!(
+            p.parse("garb garb      garb     garb     q").unwrap(),
+            (vec![20, 20, 20, 20], "q")
+        );
+    }
+}

subtrees/parser-combinator/src/combinators/optional.rs

@@ -0,0 +1,17 @@
+use crate::parser::{Parser, ParserInput, Representation};
+
+pub fn optional<P, I, O, E>(parser: P) -> impl Parser<I, Option<O>, E>
+where
+    P: Parser<I, O, E>,
+    I: ParserInput + Clone,
+{
+    let rep = Representation::from_choice(
+        &mut [parser.representation(), Representation::new("ε")].into_iter(),
+    );
+    let p = move |input: I| match parser.parse(input.clone()) {
+        Ok((output, rest)) => Ok((Some(output), rest)),
+        Err(_e) => Ok((None, input)),
+    };
+
+    (p, rep)
+}

subtrees/parser-combinator/src/combinators/repeated.rs

@@ -0,0 +1,94 @@
+use crate::combinators::separated_by::SeparatedBy;
+use crate::parser::{BoxedParser, ParseResult, Parser, ParserInput, Representation};
+
+pub fn repeated<'a, P, I, O>(parser: P) -> Repeated<'a, I, O>
+where
+    P: Parser<I, O, I> + 'a,
+    I: ParserInput + Clone + 'a,
+{
+    Repeated {
+        inner_parser: BoxedParser::new(parser),
+        at_least: None,
+        at_most: None,
+    }
+}
+
+pub struct Repeated<'a, I, O>
+where
+    I: ParserInput + Clone,
+{
+    pub(super) inner_parser: BoxedParser<'a, I, O, I>,
+    pub(super) at_least: Option<u16>,
+    pub(super) at_most: Option<u16>,
+}
+
+impl<'a, I, O> Repeated<'a, I, O>
+where
+    I: ParserInput + Clone,
+{
+    pub fn at_least(self, n: u16) -> Self {
+        Self {
+            at_least: Some(n),
+            ..self
+        }
+    }
+    pub fn at_most(self, n: u16) -> Self {
+        Self {
+            at_most: Some(n),
+            ..self
+        }
+    }
+
+    pub fn separated_by<D, O2>(self, delimiter: D, allow_trailing: bool) -> SeparatedBy<'a, I, O>
+    where
+        D: Parser<I, O2, I> + 'a,
+        O2: 'a,
+        I: 'a,
+    {
+        SeparatedBy {
+            inner_repeated: self,
+            delimiter: BoxedParser::new(delimiter.to(())),
+            allow_trailing,
+        }
+    }
+}
+
+impl<'a, I, O> Parser<I, Vec<O>, I> for Repeated<'a, I, O>
+where
+    I: ParserInput + Clone + 'a,
+{
+    fn parse(&self, input: I) -> ParseResult<I, Vec<O>, I> {
+        let at_least = self.at_least.unwrap_or(0);
+        let at_most = self.at_most.unwrap_or(u16::MAX);
+
+        if at_most == 0 {
+            return Ok((vec![], input));
+        }
+
+        let mut results = Vec::new();
+        let mut count: u16 = 0;
+        let mut further_input = input.clone();
+
+        while let Ok((item, rest)) = self.inner_parser.parse(further_input.clone()) {
+            results.push(item);
+            further_input = rest;
+            count += 1;
+            if count >= at_most {
+                break;
+            }
+        }
+        if count < at_least {
+            return Err(input);
+        }
+
+        Ok((results, further_input))
+    }
+
+    fn representation(&self) -> Representation {
+        Representation::repeated(
+            self.inner_parser.representation(),
+            self.at_least.unwrap_or(0),
+            self.at_most.unwrap_or(u16::MAX),
+        )
+    }
+}

subtrees/parser-combinator/src/combinators/separated_by.rs

@@ -0,0 +1,84 @@
+use crate::combinators::repeated::Repeated;
+use crate::parser::{BoxedParser, ParseResult, Parser, ParserInput, Representation};
+
+pub struct SeparatedBy<'a, I, O>
+where
+    I: ParserInput + Clone,
+{
+    pub(super) inner_repeated: Repeated<'a, I, O>,
+    pub(super) delimiter: BoxedParser<'a, I, (), I>,
+    pub(super) allow_trailing: bool,
+}
+
+impl<'a, I, O> Parser<I, Vec<O>, I> for SeparatedBy<'a, I, O>
+where
+    I: ParserInput + Clone + 'a,
+{
+    fn representation(&self) -> Representation {
+        Representation::new("sepby")
+    }
+
+    fn parse(&self, input: I) -> ParseResult<I, Vec<O>, I> {
+        let at_least = self.inner_repeated.at_least.unwrap_or(0);
+        let at_most = self.inner_repeated.at_most.unwrap_or(u16::MAX);
+        let parser = &self.inner_repeated.inner_parser;
+        let delimiter = &self.delimiter;
+
+        if at_most == 0 {
+            return Ok((vec![], input));
+        }
+
+        let mut results = Vec::new();
+        let mut count: u16 = 0;
+        let mut further_input;
+
+        match parser.parse(input.clone()) {
+            Ok((item, rest)) => {
+                results.push(item);
+                further_input = rest;
+            }
+            Err(_e) => {
+                if at_least > 0 {
+                    return Err(input);
+                } else {
+                    return Ok((vec![], input));
+                }
+            }
+        }
+
+        loop {
+            match delimiter.parse(further_input.clone()) {
+                Ok(((), rest)) => {
+                    further_input = rest;
+                }
+                Err(_e) => {
+                    break;
+                }
+            }
+
+            match parser.parse(further_input.clone()) {
+                Ok((item, rest)) => {
+                    results.push(item);
+                    further_input = rest;
+                    count += 1;
+                }
+                Err(_e) if self.allow_trailing => {
+                    break;
+                }
+                Err(e) => {
+                    return Err(e);
+                }
+            }
+
+            if count >= at_most {
+                break;
+            }
+        }
+
+        if count < at_least {
+            return Err(input);
+        }
+
+        Ok((results, further_input))
+    }
+}

subtrees/parser-combinator/src/lib.rs

@@ -0,0 +1,7 @@
+pub mod choice;
+pub mod combinators;
+mod parser;
+pub mod primitives;
+pub mod sequence;
+
+pub use parser::{ParseResult, Parser, ParserInput, Representation};

subtrees/parser-combinator/src/parser/boxed_parser.rs

@@ -0,0 +1,38 @@
+use crate::parser::{ParseResult, Parser, ParserInput, Representation};
+
+pub struct BoxedParser<'a, I, O, E>
+where
+    I: ParserInput,
+{
+    inner: Box<dyn Parser<I, O, E> + 'a>,
+}
+
+impl<'a, I, O, E> BoxedParser<'a, I, O, E>
+where
+    I: ParserInput,
+{
+    pub(crate) fn new<P>(inner: P) -> Self
+    where
+        P: Parser<I, O, E> + 'a,
+    {
+        BoxedParser {
+            inner: Box::new(inner),
+        }
+    }
+}
+
+impl<'a, I: ParserInput, O, E> Parser<I, O, E> for BoxedParser<'a, I, O, E> {
+    fn representation(&self) -> Representation {
+        self.inner.representation()
+    }
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        self.inner.parse(input)
+    }
+
+    fn boxed<'b>(self) -> BoxedParser<'b, I, O, E>
+    where
+        Self: Sized + 'b,
+    {
+        self
+    }
+}

subtrees/parser-combinator/src/parser/mod.rs

@@ -0,0 +1,179 @@
+mod boxed_parser;
+mod named_parser;
+mod parser_input;
+mod representation;
+
+use std::rc::Rc;
+
+pub use boxed_parser::BoxedParser;
+pub use named_parser::NamedParser;
+pub use parser_input::ParserInput;
+pub use representation::Representation;
+
+pub type ParseResult<I, O, E> = Result<(O, I), E>;
+
+pub trait Parser<I, O, E>
+where
+    I: ParserInput,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E>;
+
+    fn representation(&self) -> Representation;
+
+    fn boxed<'a>(self) -> BoxedParser<'a, I, O, E>
+    where
+        Self: Sized + 'a,
+    {
+        BoxedParser::new(self)
+    }
+
+    fn map<'a, F, O2>(self, map_fn: F) -> BoxedParser<'a, I, O2, E>
+    where
+        Self: Sized + 'a,
+        I: 'a,
+        E: 'a,
+        O: 'a,
+        O2: 'a,
+        F: Fn(O) -> O2 + 'a,
+    {
+        crate::combinators::map(self, map_fn).boxed()
+    }
+
+    fn to<'a, O2>(self, item: O2) -> BoxedParser<'a, I, O2, E>
+    where
+        Self: Sized + 'a,
+        I: 'a,
+        O: 'a,
+        O2: Clone + 'a,
+        E: 'a,
+    {
+        self.map(move |_| item.clone())
+    }
+
+    fn then<'a, P, O2>(self, next_parser: P) -> BoxedParser<'a, I, (O, O2), E>
+    where
+        Self: Sized + 'a,
+        I: 'a,
+        O: 'a,
+        O2: 'a,
+        E: 'a,
+        P: Parser<I, O2, E> + 'a,
+    {
+        crate::sequence::tuple2(self, next_parser).boxed()
+    }
+
+    fn ignore_then<'a, P, O2>(self, next_parser: P) -> BoxedParser<'a, I, O2, E>
+    where
+        Self: Sized + 'a,
+        I: 'a,
+        O: 'a,
+        O2: 'a,
+        E: 'a,
+        P: Parser<I, O2, E> + 'a,
+    {
+        crate::sequence::tuple2(self, next_parser).map(|(_, next_output)| next_output)
+    }
+
+    fn then_ignore<'a, P, O2>(self, next_parser: P) -> BoxedParser<'a, I, O, E>
+    where
+        Self: Sized + 'a,
+        I: 'a,
+        O: 'a,
+        O2: 'a,
+        E: 'a,
+        P: Parser<I, O2, E> + 'a,
+    {
+        crate::sequence::tuple2(self, next_parser).map(|(this_output, _)| this_output)
+    }
+
+    fn delimited<'a, P1, O1, P2, O2>(self, left: P1, right: P2) -> BoxedParser<'a, I, O, E>
+    where
+        Self: Sized + 'a,
+        I: 'a,
+        O1: 'a,
+        O2: 'a,
+        O: 'a,
+        E: 'a,
+        P1: Parser<I, O1, E> + 'a,
+        P2: Parser<I, O2, E> + 'a,
+    {
+        crate::sequence::seq((left, self, right)).map(|(_, output, _)| output)
+    }
+
+    fn surrounded_by<'a, P, O1>(self, surrounding: P) -> BoxedParser<'a, I, O, E>
+    where
+        Self: Sized + 'a,
+        I: 'a,
+        O1: 'a,
+        O: 'a,
+        E: 'a,
+        P: Parser<I, O1, E> + 'a,
+    {
+        BoxedParser::new(move |input| {
+            let p1 = |i| surrounding.parse(i);
+            let p2 = |i| surrounding.parse(i);
+            let main = |i| self.parse(i);
+            crate::sequence::seq((p1, main, p2))
+                .map(|(_, output, _)| output)
+                .parse(input)
+        })
+    }
+
+    fn optional<'a>(self) -> BoxedParser<'a, I, Option<O>, E>
+    where
+        I: Clone + 'a,
+        O: 'a,
+        E: 'a,
+        Self: Sized + 'a,
+    {
+        crate::combinators::optional(self).boxed()
+    }
+
+    fn named<'a>(self, parser_name: &str) -> NamedParser<'a, I, O, E>
+    where
+        Self: Sized + 'a,
+        I: 'a,
+    {
+        NamedParser::new(self.boxed(), parser_name.to_string())
+    }
+}
+
+impl<I: ParserInput, O, E, F> Parser<I, O, E> for F
+where
+    F: Fn(I) -> ParseResult<I, O, E>,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        self(input)
+    }
+
+    fn representation(&self) -> Representation {
+        Representation::new("NOT IMPL'D")
+    }
+}
+
+impl<I: ParserInput, O, E, F> Parser<I, O, E> for (F, Representation)
+where
+    F: Fn(I) -> ParseResult<I, O, E>,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        self.0(input)
+    }
+
+    fn representation(&self) -> Representation {
+        self.1.clone()
+    }
+}
+
+impl<I, O, E, T> Parser<I, O, E> for Rc<T>
+where
+    I: ParserInput,
+    T: Parser<I, O, E>,
+{
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        self.as_ref().parse(input)
+    }
+
+    fn representation(&self) -> Representation {
+        self.as_ref().representation()
+    }
+}

subtrees/parser-combinator/src/parser/named_parser.rs

@@ -0,0 +1,36 @@
+use super::boxed_parser::BoxedParser;
+use crate::parser::{ParseResult, Parser, ParserInput, Representation};
+
+pub struct NamedParser<'a, I, O, E>
+where
+    I: ParserInput,
+{
+    inner_parser: BoxedParser<'a, I, O, E>,
+    name: String,
+}
+
+impl<'a, I, O, E> NamedParser<'a, I, O, E>
+where
+    I: ParserInput,
+{
+    pub(super) fn new(inner_parser: BoxedParser<'a, I, O, E>, name: String) -> Self
+    where
+        I: 'a,
+    {
+        NamedParser { inner_parser, name }
+    }
+
+    pub fn get_name(&'a self) -> &'a str {
+        self.name.as_ref()
+    }
+}
+
+impl<'a, I: ParserInput, O, E> Parser<I, O, E> for NamedParser<'a, I, O, E> {
+    fn representation(&self) -> Representation {
+        self.inner_parser.representation()
+    }
+
+    fn parse(&self, input: I) -> ParseResult<I, O, E> {
+        self.inner_parser.parse(input)
+    }
+}