Add note about typestates

TODO.md

@@ -42,6 +42,7 @@
 ## Language Syntax
 
 * the `type` declaration should have some kind of GADT-like syntax
+* syntactic sugar for typestates? (cf. https://rustype.github.io/notes/notes/rust-typestate-series/rust-typestate-part-1.html )
 * use `let` sigil to indicate a variable in a pattern explicitly:
 
 ```

schala-lang/src/parsing/combinator.rs

@@ -616,8 +616,8 @@ fn primary_expr_no_struct(input: Span) -> ParseResult<ExpressionKind> {
             bool_literal,
             float_literal,
             number_literal,
-            string_literal,
             self_expr,
+            string_literal,
         )),
     )(input)
 }

schala-lang/src/reduced_ir/mod.rs

@@ -339,7 +339,7 @@ impl<'a, 'b> Reducer<'a, 'b> {
 
         match symbol.spec() {
             Builtin(b) => Expression::Callable(Callable::Builtin(b)),
-            Func => Expression::Lookup(Lookup::Function(def_id.unwrap())),
+            Func { .. } => Expression::Lookup(Lookup::Function(def_id.unwrap())),
             GlobalBinding => Expression::Lookup(Lookup::GlobalVar(def_id.unwrap())),
             LocalVariable => Expression::Lookup(Lookup::LocalVar(def_id.unwrap())),
             FunctionParam(n) => Expression::Lookup(Lookup::Param(n)),

schala-lang/src/symbol_table/fqsn.rs

@@ -17,6 +17,12 @@ impl Fqsn {
         Fqsn { scopes: v }
     }
 
+    pub fn extend(&self, new_item: &str) -> Self {
+        let mut new = self.clone();
+        new.scopes.push(ScopeSegment::Name(Rc::new(new_item.to_string())));
+        new
+    }
+
     #[allow(dead_code)]
     pub fn from_strs(strs: &[&str]) -> Fqsn {
         let mut scopes = vec![];

schala-lang/src/symbol_table/mod.rs

@@ -32,7 +32,7 @@ pub type DefId = Id<DefItem>;
 pub enum SymbolError {
     DuplicateName { prev_name: Fqsn, location: Location },
     DuplicateVariant { type_fqsn: Fqsn, name: String },
-    DuplicateRecord { type_name: Fqsn, location: Location, member: String },
+    DuplicateRecord { type_fqsn: Fqsn, location: Location, record: String, member: String },
     UnknownAnnotation { name: String },
     BadAnnotation { name: String, msg: String },
 }
@@ -52,7 +52,10 @@ enum NameKind {
 }
 
 #[derive(Debug)]
-struct TypeKind;
+enum TypeKind {
+    Function,
+    Constructor,
+}
 
 /// Keeps track of what names were used in a given namespace.
 struct NameTable<K> {
@@ -114,7 +117,7 @@ impl SymbolTable {
     ) -> Result<(), Vec<SymbolError>> {
         let mut populator = SymbolTablePopulator { type_context, table: self };
 
-        let errs = populator.populate_name_tables(ast);
+        let errs = populator.populate_definition_tables(ast);
         if !errs.is_empty() {
             return Err(errs);
         }
@@ -153,7 +156,8 @@ impl SymbolTable {
     /// to a Symbol, a descriptor of what that name refers to.
     fn add_symbol(&mut self, id: &ItemId, fqsn: Fqsn, spec: SymbolSpec) {
         let def_id = self.def_id_store.fresh();
-        let symbol = Rc::new(Symbol { fully_qualified_name: fqsn.clone(), spec, def_id });
+        let local_name = fqsn.last_elem();
+        let symbol = Rc::new(Symbol { fully_qualified_name: fqsn.clone(), local_name, spec, def_id });
         self.symbol_trie.insert(&fqsn, def_id);
         self.id_to_def.insert(*id, def_id);
         self.def_to_symbol.insert(def_id, symbol);
@@ -162,7 +166,8 @@ impl SymbolTable {
     fn populate_single_builtin(&mut self, fqsn: Fqsn, builtin: Builtin) {
         let def_id = self.def_id_store.fresh();
         let spec = SymbolSpec::Builtin(builtin);
-        let symbol = Rc::new(Symbol { fully_qualified_name: fqsn.clone(), spec, def_id });
+        let local_name = fqsn.last_elem();
+        let symbol = Rc::new(Symbol { fully_qualified_name: fqsn.clone(), local_name, spec, def_id });
 
         self.symbol_trie.insert(&fqsn, def_id);
         self.def_to_symbol.insert(def_id, symbol);
@@ -173,13 +178,14 @@ impl SymbolTable {
 #[derive(Debug, Clone)]
 pub struct Symbol {
     fully_qualified_name: Fqsn,
+    local_name: Rc<String>,
     spec: SymbolSpec,
     def_id: DefId,
 }
 
 impl Symbol {
-    pub fn local_name(&self) -> Rc<String> {
-        self.fully_qualified_name.last_elem()
+    pub fn local_name(&self) -> &str {
+        self.local_name.as_ref()
     }
 
     pub fn def_id(&self) -> Option<DefId> {
@@ -212,7 +218,7 @@ impl fmt::Display for Symbol {
 #[derive(Debug, Clone)]
 pub enum SymbolSpec {
     Builtin(Builtin),
-    Func,
+    Func { method: Option<crate::ast::TypeSingletonName> },
     DataConstructor { tag: u32, type_id: TypeId },
     RecordConstructor { tag: u32, type_id: TypeId },
     GlobalBinding, //Only for global variables, not for function-local ones or ones within a `let` scope context
@@ -225,7 +231,7 @@ impl fmt::Display for SymbolSpec {
         use self::SymbolSpec::*;
         match self {
             Builtin(b) => write!(f, "Builtin: {:?}", b),
-            Func => write!(f, "Func"),
+            Func { .. } => write!(f, "Func"),
             DataConstructor { tag, type_id } => write!(f, "DataConstructor(tag: {}, type: {})", tag, type_id),
             RecordConstructor { type_id, tag, .. } =>
                 write!(f, "RecordConstructor(tag: {})(<members> -> {})", tag, type_id),

schala-lang/src/symbol_table/populator.rs

@@ -1,6 +1,5 @@
 use std::{
     collections::{hash_map::Entry, HashMap, HashSet},
-    rc::Rc,
     str::FromStr,
 };
 
@@ -32,7 +31,7 @@ impl<'a> SymbolTablePopulator<'a> {
     /// constants, functions, types, and modules defined within. This simultaneously
     /// checks for dupicate definitions (and returns errors if discovered), and sets
     /// up name tables that will be used by further parts of the compiler
-    pub fn populate_name_tables(&mut self, ast: &AST) -> Vec<SymbolError> {
+    pub fn populate_definition_tables(&mut self, ast: &AST) -> Vec<SymbolError> {
         let mut scope_stack = vec![];
         self.add_from_scope(ast.statements.as_ref(), &mut scope_stack, false)
     }
@@ -51,24 +50,36 @@ impl<'a> SymbolTablePopulator<'a> {
             if let Err(err) = self.add_single_statement(id, kind, location, scope_stack, function_scope) {
                 errors.push(err);
             } else {
+                let decl = match kind {
+                    StatementKind::Declaration(decl) => decl,
+                    _ => continue,
+                };
                 // If there's an error with a name, don't recurse into subscopes of that name
-                let recursive_errs = match kind {
-                    StatementKind::Declaration(Declaration::FuncDecl(signature, body)) => {
+                let recursive_errs = match decl {
+                    Declaration::FuncDecl(signature, body) => {
                         let new_scope = ScopeSegment::Name(signature.name.clone());
                         scope_stack.push(new_scope);
                         let output = self.add_from_scope(body.as_ref(), scope_stack, true);
                         scope_stack.pop();
                         output
                     }
-                    StatementKind::Declaration(Declaration::Module { name, items }) => {
+                    Declaration::Module { name, items } => {
                         let new_scope = ScopeSegment::Name(name.clone());
                         scope_stack.push(new_scope);
                         let output = self.add_from_scope(items.as_ref(), scope_stack, false);
                         scope_stack.pop();
                         output
                     }
-                    StatementKind::Declaration(Declaration::TypeDecl { name, body, mutable }) =>
-                        self.add_type_members(name, body, mutable, location, scope_stack),
+                    Declaration::TypeDecl { name, body, mutable } => {
+                        let type_fqsn = Fqsn::from_scope_stack(scope_stack, name.name.clone());
+                        self.add_type_members(name, body, mutable, location, type_fqsn)
+                    }
+
+                    /*
+                    Declaration::Impl { type_name, body, .. } => {
+
+                    },
+                        */
                     _ => vec![],
                 };
                 errors.extend(recursive_errs.into_iter());
@@ -92,9 +103,11 @@ impl<'a> SymbolTablePopulator<'a> {
                 self.table
                     .fq_names
                     .register(fq_function.clone(), NameSpec { location, kind: NameKind::Function })?;
-                self.table.types.register(fq_function.clone(), NameSpec { location, kind: TypeKind })?;
+                self.table
+                    .types
+                    .register(fq_function.clone(), NameSpec { location, kind: TypeKind::Function })?;
 
-                self.add_symbol(id, fq_function, SymbolSpec::Func);
+                self.add_symbol(id, fq_function, SymbolSpec::Func { method: None });
             }
             StatementKind::Declaration(Declaration::FuncDecl(signature, ..)) => {
                 let fn_name = &signature.name;
@@ -102,13 +115,15 @@ impl<'a> SymbolTablePopulator<'a> {
                 self.table
                     .fq_names
                     .register(fq_function.clone(), NameSpec { location, kind: NameKind::Function })?;
-                self.table.types.register(fq_function.clone(), NameSpec { location, kind: TypeKind })?;
+                self.table
+                    .types
+                    .register(fq_function.clone(), NameSpec { location, kind: TypeKind::Function })?;
 
-                self.add_symbol(id, fq_function, SymbolSpec::Func);
+                self.add_symbol(id, fq_function, SymbolSpec::Func { method: None });
             }
             StatementKind::Declaration(Declaration::TypeDecl { name, .. }) => {
                 let fq_type = Fqsn::from_scope_stack(scope_stack, name.name.clone());
-                self.table.types.register(fq_type, NameSpec { location, kind: TypeKind })?;
+                self.table.types.register(fq_type, NameSpec { location, kind: TypeKind::Constructor })?;
             }
             StatementKind::Declaration(Declaration::Binding { name, .. }) => {
                 let fq_binding = Fqsn::from_scope_stack(scope_stack, name.clone());
@@ -190,7 +205,7 @@ impl<'a> SymbolTablePopulator<'a> {
         type_body: &TypeBody,
         _mutable: &bool,
         location: Location,
-        scope_stack: &mut Vec<ScopeSegment>,
+        type_fqsn: Fqsn,
     ) -> Vec<SymbolError> {
         let (variants, immediate_variant) = match type_body {
             TypeBody::Variants(variants) => (variants.clone(), false),
@@ -203,10 +218,6 @@ impl<'a> SymbolTablePopulator<'a> {
                 true,
             ),
         };
-        let type_fqsn = Fqsn::from_scope_stack(scope_stack, type_name.name.clone());
-
-        let new_scope = ScopeSegment::Name(type_name.name.clone());
-        scope_stack.push(new_scope);
 
         // Check for duplicates before registering any types with the TypeContext
         let mut seen_variants = HashSet::new();
@@ -222,15 +233,15 @@ impl<'a> SymbolTablePopulator<'a> {
             seen_variants.insert(variant.name.clone());
 
             if let VariantKind::Record(ref members) = variant.kind {
-                let variant_name = Fqsn::from_scope_stack(scope_stack.as_ref(), variant.name.clone());
                 let mut seen_members = HashMap::new();
                 for (member_name, _) in members.iter() {
                     match seen_members.entry(member_name.as_ref()) {
                         Entry::Occupied(o) => {
                             let location = *o.get();
                             errors.push(SymbolError::DuplicateRecord {
-                                type_name: variant_name.clone(),
+                                type_fqsn: type_fqsn.clone(),
                                 location,
+                                record: variant.name.as_ref().to_string(),
                                 member: member_name.as_ref().to_string(),
                             });
                         }
@@ -249,11 +260,11 @@ impl<'a> SymbolTablePopulator<'a> {
 
         let mut type_builder = TypeBuilder::new(type_name.name.as_ref());
 
-        let mut fqsn_id_map = HashMap::new();
+        let mut variant_name_map = HashMap::new();
         for variant in variants.iter() {
             let Variant { name, kind, id } = variant;
 
-            fqsn_id_map.insert(Fqsn::from_scope_stack(scope_stack.as_ref(), name.clone()), id);
+            variant_name_map.insert(name.clone(), id);
 
             let mut variant_builder = VariantBuilder::new(name.as_ref());
             match kind {
@@ -277,30 +288,23 @@ impl<'a> SymbolTablePopulator<'a> {
 
         // This index is guaranteed to be the correct tag
         for (index, variant) in type_definition.variants.iter().enumerate() {
-            let fqsn = Fqsn::from_scope_stack(scope_stack.as_ref(), Rc::new(variant.name.to_string()));
-            let id = fqsn_id_map.get(&fqsn).unwrap();
+            let id = variant_name_map.get(&variant.name).unwrap();
             let tag = index as u32;
             let spec = match &variant.members {
                 type_inference::VariantMembers::Unit => SymbolSpec::DataConstructor { tag, type_id },
                 type_inference::VariantMembers::Tuple(..) => SymbolSpec::DataConstructor { tag, type_id },
                 type_inference::VariantMembers::Record(..) => SymbolSpec::RecordConstructor { tag, type_id },
             };
-            self.table.add_symbol(id, fqsn, spec);
+            self.table.add_symbol(id, type_fqsn.extend(&variant.name), spec);
         }
 
         if immediate_variant {
             let variant = &type_definition.variants[0];
-            let fqsn = Fqsn::from_scope_stack(scope_stack.as_ref(), Rc::new(variant.name.to_string()));
-            let id = fqsn_id_map.get(&fqsn).unwrap();
-            let abbrev_fqsn = Fqsn::from_scope_stack(
-                scope_stack[0..scope_stack.len() - 1].as_ref(),
-                Rc::new(variant.name.to_string()),
-            );
+            let id = variant_name_map.get(&variant.name).unwrap();
             let spec = SymbolSpec::RecordConstructor { tag: 0, type_id };
-            self.table.add_symbol(id, abbrev_fqsn, spec);
+            self.table.add_symbol(id, type_fqsn, spec);
         }
 
-        scope_stack.pop();
         vec![]
     }
 }

schala-lang/src/symbol_table/test.rs

@@ -263,10 +263,29 @@ fn duplicate_struct_members() {
     "#;
 
     let (_, output) = add_symbols(source);
-    let errs = output.unwrap_err();
+    let errs = dbg!(output.unwrap_err());
     assert_matches!(&errs[..], [
       SymbolError::DuplicateRecord {
-        type_name, member, ..},
-    ] if type_name == &Fqsn::from_strs(&["Tarak", "Tarak"]) && member == "mets"
+        type_fqsn, member, record, ..},
+    ] if type_fqsn == &Fqsn::from_strs(&["Tarak"]) && member == "mets" && record == "Tarak"
     );
 }
+
+/*
+#[test]
+fn methods() {
+    let source = r#"
+
+type Foo = { x: Int, y: Int }
+
+impl Foo {
+    fn hella() {
+        self.x + 50
+    }
+}
+"#;
+    let (symbols, _) = add_symbols(source);
+    symbols.debug();
+    assert!(symbols.fq_names.table.get(&make_fqsn(&["hella"])).is_some());
+}
+*/