From c1e6bc8c4cd7c5403b0f33f86dc8b34e570d930a Mon Sep 17 00:00:00 2001
From: Greg Shuflin <greg.shuflin@protonmail.com>
Date: Wed, 17 Nov 2021 16:44:09 -0800
Subject: [PATCH] MOre work

---
 schala-lang/src/parsing/combinator.rs | 70 ++++++++++++++++++++++++++-
 1 file changed, 69 insertions(+), 1 deletion(-)

diff --git a/schala-lang/src/parsing/combinator.rs b/schala-lang/src/parsing/combinator.rs
index 24e420e..444cc5f 100644
--- a/schala-lang/src/parsing/combinator.rs
+++ b/schala-lang/src/parsing/combinator.rs
@@ -32,6 +32,11 @@ fn fresh_id(span: &Span) -> Id<ASTItem> {
     table_handle.fresh()
 }
 
+fn fresh_id_rc(store_ref: &StoreRef) -> Id<ASTItem> {
+    let mut table_handle = store_ref.borrow_mut();
+    table_handle.fresh()
+}
+
 fn tok<'a, O>(
     input_parser: impl Parser<Span<'a>, O, VerboseError<Span<'a>>>,
 ) -> impl FnMut(Span<'a>) -> IResult<Span<'a>, O, VerboseError<Span<'a>>> {
@@ -127,7 +132,50 @@ fn type_singleton_name(input: Span) -> ParseResult<TypeSingletonName> {
 }
 
 pub fn expression_kind(input: Span) -> ParseResult<ExpressionKind> {
-    context("expression-kind", primary_expr)(input)
+    context("expression-kind", prefix_expr)(input)
+}
+
+fn precedence_expr(input: Span) -> ParseResult<ExpressionKind> {
+    map(pair(prefix_expr, many0(precedence_continuation)),
+    |(first, rest): (ExpressionKind, Vec<(BinOp, ExpressionKind)>)| unimplemented!())(input)
+}
+
+fn precedence_continuation(input: Span) -> ParseResult<(BinOp, ExpressionKind)> {
+    pair(operator, prefix_expr)(input)
+}
+
+fn operator(input: Span) -> ParseResult<BinOp> {
+    tok(
+    map(
+    tuple((
+        not(tag("*/")),
+        recognize(many1(one_of("+-*/%<>=!$&|?^`"))),
+    )), |(_, sigil_span): ((), Span)| BinOp::from_sigil(sigil_span.fragment())))(input)
+}
+
+fn prefix_op(input: Span) -> ParseResult<PrefixOp> {
+    tok(
+        map(recognize(one_of("+-!")),
+        |sigil: Span| PrefixOp::from_sigil(sigil.fragment())))(input)
+}
+
+fn prefix_expr(input: Span) -> ParseResult<ExpressionKind> {
+    let handle = input.extra.clone();
+    context("prefix-expr",
+    map(
+    pair(opt(prefix_op), extended_expr), move |(prefix, expr)| {
+        if let Some(prefix) = prefix {
+            let expr = Expression::new(fresh_id_rc(&handle), expr);
+            ExpressionKind::PrefixExp(prefix, Box::new(expr))
+        } else {
+            expr
+        }
+    }))(input)
+}
+
+fn extended_expr(input: Span) -> ParseResult<ExpressionKind> {
+    context("extended-expr",
+    primary_expr)(input)
 }
 
 fn primary_expr(input: Span) -> ParseResult<ExpressionKind> {
@@ -295,6 +343,26 @@ mod test {
             span!(expression_kind, " /*yolo*/  barnaby").unwrap().1,
             ExpressionKind::Value(qn!(barnaby))
         );
+
+
+        let source = "!4";
+        let parsed = span!(expression_kind, source).map_err(|err| match err {
+            Err::Error(err) | Err::Failure(err) => {
+                let err = VerboseError {
+                    errors: err.errors.into_iter().map(|(sp, kind)| (*sp.fragment(), kind)).collect(),
+                };
+                nom::error::convert_error(source, err)
+            }
+            _ => panic!(),
+        });
+
+        if let Err(err) = parsed {
+            println!("{}", err);
+            panic!("parse error desu!");
+        }
+
+        assert_eq!(parsed.unwrap().1, ExpressionKind::PrefixExp(PrefixOp::from_sigil("!"),
+        Box::new(Expression::new(Default::default(), ExpressionKind::NatLiteral(4)))));
     }
 
     #[test]