feat: function (WIP)

src/bytecode.rs

@@ -1,6 +1,6 @@
 use ecow::EcoString;
 
-use crate::ty::internal::{Const, Param};
+use crate::ty::internal::Const;
 
 type Slice<T> = Box<[T]>;
 
@@ -35,7 +35,17 @@ pub enum OpCode {
     /// return a value
     Ret,
     /// make a function
-    Func { param: Param, length: usize },
+    Func { idx: ThunkIdx },
+    /// push param `sym` into TOS
+    PushIdentParam { sym: EcoString },
+    /// push formal param `sym` into TOS
+    PushFormalParam { sym: EcoString },
+    /// push default formal param with thunkidx `idx` into TOS
+    PushDefaultParam { idx: ThunkIdx },
+    /// TODO:
+    SetEllipsis,
+    /// TODO:
+    SetAlias { sym: EcoString },
 
     /// consume 1 element, assert TOS is true
     Assert,