refactor: remove find_with_depth method from Scope (#76)

junlarsen · Feb 15, 2025 · 982c991 · 982c991
1 parent 6e6519a
commit 982c991
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Showing 3 changed files with 15 additions and 31 deletions.
diff --git a/compiler/eight-middle/src/passes/hir_type_check_pass/mod.rs b/compiler/eight-middle/src/passes/hir_type_check_pass/mod.rs
@@ -393,7 +393,7 @@ impl HirModuleTypeCheckerPass {
             ice!("visit_nominal_ty called with non-nominal type");
         };
         // Check if the name refers to a generic type parameter, like `T`.
-        if let Some(sub) = cx.find_type_binding(n.name) {
+        if let Some((sub, _)) = cx.find_type_binding(n.name) {
             return Ok(sub);
         }
         // Check if the name refers to a struct or a type.

diff --git a/compiler/eight-middle/src/passes/hir_type_check_pass/typing_context.rs b/compiler/eight-middle/src/passes/hir_type_check_pass/typing_context.rs
@@ -44,7 +44,7 @@ pub struct TypingContext<'hir> {
     ///
     /// We currently don't support nested functions or lambdas, so this does not necessarily have to
     /// be a VecDeque, but it's here for future use.
-    type_binding_context: Scope<&'hir str, &'hir HirTy<'hir>>,
+    type_binding_context: Scope<&'hir str, (&'hir HirTy<'hir>, Span)>,
     let_binding_context: Scope<&'hir str, (&'hir HirTy<'hir>, Span)>,
     // TODO: make private
     pub type_parameter_instantiations: Scope<(u32, u32), &'hir HirTy<'hir>>,
@@ -120,17 +120,19 @@ impl<'hir> TypingContext<'hir> {
         ty: &'hir HirTy<'hir>,
     ) -> HirResult<()> {
         let current_depth = self.type_binding_context.depth();
-        if let Some((depth, _)) = self.type_binding_context.find_with_depth(&name) {
-            if depth >= current_depth {
-                return Err(HirError::TypeParameterShadowsExisting(
-                    TypeParameterShadowsExisting {
-                        name: name.to_owned(),
-                        span,
-                    },
-                ));
-            }
+        if self
+            .type_binding_context
+            .find_within_depth(&name, current_depth)
+            .is_some()
+        {
+            return Err(HirError::TypeParameterShadowsExisting(
+                TypeParameterShadowsExisting {
+                    name: name.to_owned(),
+                    span,
+                },
+            ));
         }
-        self.type_binding_context.add(name, ty);
+        self.type_binding_context.add(name, (ty, span));
         Ok(())
     }
 
@@ -167,7 +169,7 @@ impl<'hir> TypingContext<'hir> {
     }
 
     /// Find the type of a type binding.
-    pub fn find_type_binding(&self, name: &'hir str) -> Option<&'hir HirTy<'hir>> {
+    pub fn find_type_binding(&self, name: &'hir str) -> Option<(&'hir HirTy<'hir>, Span)> {
         self.type_binding_context.find(&name).copied()
     }
 

diff --git a/compiler/eight-middle/src/scope.rs b/compiler/eight-middle/src/scope.rs
@@ -54,16 +54,6 @@ impl<K: Ord, V> Scope<K, V> {
         None
     }
 
-    /// Find an item in the context, and return the distance from the root scope.
-    pub fn find_with_depth(&self, name: &K) -> Option<(usize, &V)> {
-        for (depth, scope) in self.scopes.iter().enumerate() {
-            if let Some(item) = scope.get(name) {
-                return Some((depth, item));
-            }
-        }
-        None
-    }
-
     pub fn add(&mut self, name: K, id: V) {
         let scope = self
             .scopes
@@ -79,14 +69,6 @@ impl<K: Ord, V> Scope<K, V> {
             .unwrap_or_else(|| ice!("local context has no scope"));
         scope.remove(name);
     }
-
-    pub fn local_size(&self) -> usize {
-        self.scopes.front().map(|s| s.len()).unwrap_or(0)
-    }
-
-    pub fn find_local(&self, name: &K) -> Option<&V> {
-        self.scopes.front().and_then(|s| s.get(name))
-    }
 }
 
 #[cfg(test)]