From 27db67dd9966889da54382da4790db7835922ab3 Mon Sep 17 00:00:00 2001
From: sofia <sofia@teascade.net>
Date: Thu, 24 Jul 2025 18:42:10 +0300
Subject: [PATCH] Possibly fix typechecking for binops

---
 examples/hello_world.reid     |  2 +-
 reid/src/ast/parse.rs         |  2 +-
 reid/src/mir/pass.rs          |  6 ++++--
 reid/src/mir/typecheck.rs     | 32 +++++++++++++++++++++++---------
 reid/src/mir/typeinference.rs |  1 +
 reid/src/mir/typerefs.rs      |  7 ++++++-
 6 files changed, 36 insertions(+), 14 deletions(-)

diff --git a/examples/hello_world.reid b/examples/hello_world.reid
index bf34034..1e97fe6 100644
--- a/examples/hello_world.reid
+++ b/examples/hello_world.reid
@@ -21,5 +21,5 @@ fn main() -> u8 {
 
     free_string(&test);
 
-    return addition(5, 3);
+    return 8;
 }
diff --git a/reid/src/ast/parse.rs b/reid/src/ast/parse.rs
index a44e2a2..4bf5e82 100644
--- a/reid/src/ast/parse.rs
+++ b/reid/src/ast/parse.rs
@@ -314,7 +314,7 @@ fn parse_binop_rhs(
 
         lhs = Expression(
             ExpressionKind::Binop(op, Box::new(lhs), Box::new(rhs)),
-            stream.get_range().unwrap(),
+            stream.get_range_prev().unwrap(),
         );
     }
 
diff --git a/reid/src/mir/pass.rs b/reid/src/mir/pass.rs
index 9595166..9f085c6 100644
--- a/reid/src/mir/pass.rs
+++ b/reid/src/mir/pass.rs
@@ -115,6 +115,10 @@ impl<Key: std::hash::Hash + Eq, T: Clone + std::fmt::Debug> Storage<Key, T> {
     pub fn iter(&self) -> impl Iterator<Item = (&Key, &T)> {
         self.0.iter()
     }
+
+    pub fn find(&self, key: &Key) -> Option<(&Key, &T)> {
+        self.0.iter().find(|(k, _)| *k == key)
+    }
 }
 
 #[derive(Clone, Default, Debug)]
@@ -216,7 +220,6 @@ impl std::hash::Hash for ScopeBinopKey {
 pub struct ScopeBinopDef {
     pub hands: (TypeKind, TypeKind),
     pub operator: BinaryOperator,
-    pub commutative: bool,
     pub return_ty: TypeKind,
 }
 
@@ -370,7 +373,6 @@ impl Module {
                     ScopeBinopDef {
                         hands: (binop.lhs.1.clone(), binop.rhs.1.clone()),
                         operator: binop.op,
-                        commutative: true,
                         return_ty: binop.return_type.clone(),
                     },
                 )
diff --git a/reid/src/mir/typecheck.rs b/reid/src/mir/typecheck.rs
index 08d5ddc..d05e33e 100644
--- a/reid/src/mir/typecheck.rs
+++ b/reid/src/mir/typecheck.rs
@@ -514,14 +514,28 @@ impl Expression {
                 let rhs_res = rhs.typecheck(state, &typerefs, None);
                 let rhs_type = state.or_else(rhs_res, TypeKind::Vague(Vague::Unknown), rhs.1);
 
-                let operator = state
-                    .scope
-                    .binops
-                    .get(&pass::ScopeBinopKey {
-                        params: (lhs_type.clone(), rhs_type.clone()),
-                        operator: *op,
-                    })
-                    .cloned();
+                let cloned = state.scope.binops.clone();
+                let mut iter = cloned.iter();
+                let operator = loop {
+                    let Some((_, binop)) = iter.next() else {
+                        break None;
+                    };
+                    if binop.operator != *op {
+                        continue;
+                    }
+                    if let Some(hint_t) = hint_t {
+                        if binop.return_ty == *hint_t {
+                            if let Some(_) = TypeKind::binop_type(&lhs_type, &rhs_type, binop) {
+                                break Some(binop);
+                            }
+                        } else {
+                            continue;
+                        }
+                    }
+                    if let Some(_) = TypeKind::binop_type(&lhs_type, &rhs_type, binop) {
+                        break Some(binop);
+                    }
+                };
 
                 if let Some(operator) = operator {
                     // Re-typecheck with found operator hints
@@ -534,7 +548,7 @@ impl Expression {
                     let rhs_res = rhs.typecheck(state, &typerefs, Some(&rhs_ty));
                     state.or_else(lhs_res, TypeKind::Vague(Vague::Unknown), lhs.1);
                     state.or_else(rhs_res, TypeKind::Vague(Vague::Unknown), rhs.1);
-                    Ok(operator.return_ty)
+                    Ok(operator.return_ty.clone())
                 } else {
                     // Re-typecheck with typical everyday binop
                     let lhs_res = lhs.typecheck(
diff --git a/reid/src/mir/typeinference.rs b/reid/src/mir/typeinference.rs
index 395c932..55a99df 100644
--- a/reid/src/mir/typeinference.rs
+++ b/reid/src/mir/typeinference.rs
@@ -311,6 +311,7 @@ impl Expression {
                 // Infer LHS and RHS, and return binop type
                 let mut lhs_ref = lhs.infer_types(state, type_refs)?;
                 let mut rhs_ref = rhs.infer_types(state, type_refs)?;
+
                 type_refs
                     .binop(op, &mut lhs_ref, &mut rhs_ref, &state.scope.binops)
                     .ok_or(ErrorKind::TypesIncompatible(
diff --git a/reid/src/mir/typerefs.rs b/reid/src/mir/typerefs.rs
index e000e84..801664e 100644
--- a/reid/src/mir/typerefs.rs
+++ b/reid/src/mir/typerefs.rs
@@ -233,11 +233,16 @@ impl<'outer> ScopeTypeRefs<'outer> {
         rhs: &mut TypeRef<'outer>,
         binops: &Storage<ScopeBinopKey, ScopeBinopDef>,
     ) -> Option<TypeRef<'outer>> {
+        if lhs.resolve_deep().unwrap().known().is_err()
+            && rhs.resolve_deep().unwrap().known().is_err()
+        {
+            return self.from_type(&TypeKind::Vague(VagueType::Unknown));
+        }
         for (_, binop) in binops.iter() {
             if let Some(ret) = try_binop(lhs, rhs, binop) {
                 return Some(ret);
             }
-            if binop.commutative {
+            if binop.operator.is_commutative() {
                 if let Some(ret) = try_binop(rhs, lhs, binop) {
                     return Some(ret);
                 }