From 6ebf31e2a007a1e58fca5fcd84e38f7ae97bd449 Mon Sep 17 00:00:00 2001
From: Michael Schimmel <schimmel@mycelium.de>
Date: Thu, 5 Mar 2026 14:35:29 +0100
Subject: [PATCH] Refactor specializer to not fold scalars

The specializer now correctly identifies when a compiled value is a
scalar and avoids folding it into a constant node. Instead, it updates
the callee to the specialized version if it's an object. This ensures
that scalar folding does not interfere with the program's execution.
---
 src/ast/compiler/specializer.rs | 48 +++++++++++----------------------
 src/ast/vm.rs                   |  2 +-
 2 files changed, 16 insertions(+), 34 deletions(-)

diff --git a/src/ast/compiler/specializer.rs b/src/ast/compiler/specializer.rs
index 83a27c9..c64204b 100644
--- a/src/ast/compiler/specializer.rs
+++ b/src/ast/compiler/specializer.rs
@@ -233,39 +233,21 @@ impl Specializer {
             self.cache
                 .borrow_mut()
                 .insert(key, (compiled_val.clone(), ret_ty.clone()));
-            let flat_elements = match &new_args.kind {
-                BoundKind::Tuple { elements } => elements.clone(),
-                _ => vec![Rc::new(new_args.clone())],
-            };
-            let flat_types = flat_elements
-                .iter()
-                .map(|e| e.ty.original.ty.clone())
-                .collect();
-            let flattened_args = Node {
-                identity: new_args.identity.clone(),
-                kind: BoundKind::Tuple {
-                    elements: flat_elements,
-                },
-                ty: NodeMetrics {
-                    original: Rc::new(Node {
-                        identity: new_args.identity.clone(),
-                        kind: BoundKind::Tuple { elements: vec![] },
-                        ty: StaticType::Tuple(flat_types),
-                    }),
-                    purity: new_args.ty.purity,
-                    is_recursive: new_args.ty.is_recursive,
-                },
-            };
-
-            let specialized_callee = self.make_constant_node(
-                compiled_val,
-                StaticType::Function(Box::new(Signature {
-                    params: flattened_args.ty.original.ty.clone(),
-                    ret: ret_ty.clone(),
-                })),
-                &new_callee,
-            );
-            return (specialized_callee, flattened_args, ret_ty);
+            
+            // Only replace the callee if the compiled value is actually a function/object.
+            // If it's a scalar (like 30 from folding), we DON'T fold here.
+            // We keep the Call but update the callee to the specialized version if it's an object.
+            if let Value::Object(_) | Value::Function(_) = &compiled_val {
+                let specialized_callee = self.make_constant_node(
+                    compiled_val,
+                    StaticType::Function(Box::new(Signature {
+                        params: StaticType::Tuple(arg_types),
+                        ret: ret_ty.clone(),
+                    })),
+                    &new_callee,
+                );
+                return (specialized_callee, new_args, ret_ty);
+            }
         }
 
         (new_callee, new_args, original_ty)
diff --git a/src/ast/vm.rs b/src/ast/vm.rs
index 0b3eea5..40cc314 100644
--- a/src/ast/vm.rs
+++ b/src/ast/vm.rs
@@ -783,7 +783,7 @@ impl VM {
                     }
 
                     match &curr.kind {
-                        BoundKind::Constant(v) => self.stack.push(v.clone()),
+                        BoundKind::Constant(v) if !O::ACTIVE => self.stack.push(v.clone()),
                         _ => {
                             let val = self.eval_internal(obs, curr)?;
                             self.stack.push(val);