feat: gc (does compile, but WIP)

src/bytecode.rs

@@ -1,6 +1,6 @@
-use hashbrown::HashMap;
 use ecow::EcoString;
 use gc_arena::Collect;
+use hashbrown::HashMap;
 
 use crate::ty::common::Const;
 use crate::ty::internal::Param;
@@ -18,10 +18,14 @@ pub enum OpCode {
     LookUp { sym: usize },
     /// load a thunk lazily onto stack
     LoadThunk { idx: usize },
+    /// load a thunk value onto stack
+    LoadValue { idx: usize },
     /// let TOS capture current environment
     CaptureEnv,
     /// force TOS to value
     ForceValue,
+    /// TODO:
+    InsertValue,
 
     /// [ .. func arg ] consume 2 elements, call `func` with arg
     Call,
@@ -73,18 +77,19 @@ pub enum OpCode {
     SelectDynamicOrDefault,
     /// enter the let environment of the attribute set at TOS
     EnterLetEnv,
-    /// exit current let envrironment
-    LeaveLetEnv,
     /// enter the with environment of the attribute set at TOS
     EnterWithEnv,
-    /// exit current with envrironment
-    LeaveWithEnv,
+    /// exit current envrironment
+    LeaveEnv,
+    /// TODO:
+    PopEnv,
 
     /// illegal operation, used as termporary placeholder
     Illegal,
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, Collect)]
+#[collect(no_drop)]
 pub enum BinOp {
     Add,
     Sub,
@@ -98,7 +103,8 @@ pub enum BinOp {
     Upd,
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, Collect)]
+#[collect(no_drop)]
 pub enum UnOp {
     Neg,
     Not,