fix incorrect behavior of nested lambdas capturing non-captures of th…

…eir parent
luminalang · Dec 8, 2024 · e10122b · e10122b
1 parent 7b4dc20
commit e10122b
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Showing 3 changed files with 7 additions and 39 deletions.
diff --git a/lumina-compiler/src/hir/expr.rs b/lumina-compiler/src/hir/expr.rs
@@ -416,20 +416,19 @@ impl<'t, 'a, 's> FuncLower<'t, 'a, 's> {
         let lkey = self
             .lambdas
             .create_placeholder(body.span, Forall::new(0), typing);
-        self.bindings.reference_lambda(lkey);
 
         self.bindings.enter();
         self.type_info.enter_lambda(lkey, Forall::new(0));
 
         let patterns = self.patterns(apatterns);
         let expr = self.expr(body);
 
-        let (captures, lcaptures) = self.bindings.leave();
+        let captures = self.bindings.leave();
         let forall = self.type_info.leave_function();
         assert!(forall.generics.is_empty());
 
         self.lambdas
-            .complete_lambda("lambda", lkey, expr, patterns, captures, lcaptures);
+            .complete_lambda("lambda", lkey, expr, patterns, captures);
 
         lkey
     }

diff --git a/lumina-compiler/src/hir/mod.rs b/lumina-compiler/src/hir/mod.rs
@@ -549,9 +549,6 @@ pub struct Lambdas<'s> {
     pub params: Map<key::Lambda, Vec<Tr<Pattern<'s>>>>,
     pub bodies: Map<key::Lambda, Tr<Expr<'s>>>,
     pub captures: Map<key::Lambda, Vec<key::Bind>>,
-    // If this lambda references other lambdas, it'll need to inherit it's captures even though
-    // they aren't directly references. (Since they will be references in the next lower)
-    pub capture_lambdas: Map<key::Lambda, Vec<key::Lambda>>,
 }
 
 impl<'s> Lambdas<'s> {
@@ -569,7 +566,6 @@ impl<'s> Lambdas<'s> {
         self.params.push_as(lkey, vec![]);
         self.bodies.push_as(lkey, Expr::Poison.tr(span));
         self.captures.push_as(lkey, vec![]);
-        self.capture_lambdas.push_as(lkey, vec![]);
         lkey
     }
 
@@ -580,13 +576,11 @@ impl<'s> Lambdas<'s> {
         expr: Tr<Expr<'s>>,
         patterns: Vec<Tr<Pattern<'s>>>,
         captures: Vec<key::Bind>,
-        capture_lambdas: Vec<key::Lambda>,
     ) {
         self.names[key] = name;
         self.bodies[key] = expr;
         self.params[key] = patterns;
         self.captures[key] = captures;
-        self.capture_lambdas[key] = capture_lambdas;
     }
 
     pub fn is_empty(&self) -> bool {
@@ -699,22 +693,6 @@ impl<'t, 'a, 's> FuncLower<'t, 'a, 's> {
         let mut func = FuncDef::new(RefCell::new(forall), typing, list, params, expr, no_mangle);
         func.lambdas = self.lambdas;
 
-        // Copy all captures used by child lambda into the captures of the parent lambda for nesting
-        for lambda in func.lambdas.keys() {
-            for child in std::mem::take(&mut func.lambdas.capture_lambdas[lambda]) {
-                if lambda == child {
-                    continue;
-                }
-
-                let [lcap, ccap] = func.lambdas.captures.get_many_mut([lambda, child]);
-                for bind in ccap {
-                    if !lcap.contains(bind) {
-                        lcap.push(*bind);
-                    }
-                }
-            }
-        }
-
         info!(
             "func lowered to:\n {} {} {} {func}",
             "fn".keyword(),
@@ -784,10 +762,10 @@ impl<'t, 'a, 's> FuncLower<'t, 'a, 's> {
             );
 
             let expr = self.expr(lbody.expr.as_ref());
-            let (captures, lcaptures) = self.bindings.leave();
+            let captures = self.bindings.leave();
             let name = *fdecl.header.name;
             self.lambdas
-                .complete_lambda(name, lkey, expr, patterns, captures, lcaptures);
+                .complete_lambda(name, lkey, expr, patterns, captures);
         }
 
         (params, expr)
@@ -810,7 +788,6 @@ impl<'t, 'a, 's> FuncLower<'t, 'a, 's> {
                 .position(|decl| *decl.header.name == name)
             {
                 let lkey = key::Lambda::from(i);
-                self.bindings.reference_lambda(lkey);
                 return Some((Callable::Lambda(lkey), ToAnnotate::Some(None)));
             }
 

diff --git a/lumina-compiler/src/hir/scope.rs b/lumina-compiler/src/hir/scope.rs
@@ -10,7 +10,6 @@ pub struct Bindings<'s> {
 struct Scope<'s> {
     binds: Vec<(key::Bind, &'s str)>,
     captures: Vec<key::Bind>,
-    references_lambdas: Vec<key::Lambda>,
 }
 
 impl<'s> Default for Bindings<'s> {
@@ -29,17 +28,9 @@ impl<'s> Bindings<'s> {
     pub fn enter(&mut self) {
         self.scopes.push(Scope::default());
     }
-    pub fn leave(&mut self) -> (Captures, Vec<key::Lambda>) {
+    pub fn leave(&mut self) -> Captures {
         let scope = self.scopes.pop().unwrap();
-        (scope.captures, scope.references_lambdas)
-    }
-
-    pub fn reference_lambda(&mut self, lambda: key::Lambda) {
-        self.scopes
-            .last_mut()
-            .unwrap()
-            .references_lambdas
-            .push(lambda);
+        scope.captures
     }
 
     pub fn declare_nameless(&mut self) -> key::Bind {
@@ -73,6 +64,7 @@ impl<'s> Bindings<'s> {
             .or_else(|| {
                 Self::resolve_in(xs, name).map(|bind| {
                     if !scope.captures.contains(&bind) {
+                        trace!("capturing {bind}");
                         scope.captures.push(bind);
                     }
                     bind