feat: function (WIP)

src/ty/internal/func.rs

@@ -1,7 +1,7 @@
 use ecow::EcoString;
 
-use crate::ty::internal::Value;
 use crate::bytecode::{OpCodes, ThunkIdx};
+use crate::ty::internal::Value;
 
 #[derive(Debug, Clone)]
 pub enum Param {
@@ -15,14 +15,65 @@ pub enum Param {
 
 #[derive(Debug, Clone)]
 pub struct Func {
-    pub param: Param,
-    pub opcodes: OpCodes
+    pub param: Option<Param>,
+    pub opcodes: OpCodes,
 }
 
 impl Func {
+    pub fn new(opcodes: OpCodes) -> Func {
+        Func {
+            param: None,
+            opcodes,
+        }
+    }
+
     pub fn call(self, _arg: Value) -> Value {
         todo!()
     }
+
+    pub fn push_ident_param(&mut self, param: EcoString) {
+        self.param = Some(Param::Ident(param))
+    }
+
+    pub fn push_formal_param(&mut self, param: EcoString) {
+        let Param::Formals { formals, .. } = self.param.get_or_insert_with(|| Param::Formals {
+            formals: Vec::with_capacity(1),
+            ellipsis: false,
+            alias: None,
+        }) else {
+            panic!()
+        };
+        formals.push((param, None));
+    }
+
+    pub fn push_default_param(&mut self, default: ThunkIdx) {
+        let Param::Formals { formals, .. } = self.param.as_mut().unwrap() else {
+            panic!()
+        };
+        formals.last_mut().unwrap().1 = Some(default)
+    }
+
+    pub fn set_ellipsis(&mut self) {
+        let Param::Formals { ellipsis, .. } = self.param.get_or_insert_with(|| Param::Formals {
+            formals: Vec::new(),
+            ellipsis: false,
+            alias: None,
+        }) else {
+            panic!()
+        };
+        *ellipsis = true;
+    }
+
+    pub fn set_alias(&mut self, sym: EcoString) {
+        let Param::Formals { alias, .. } = self.param.get_or_insert_with(|| Param::Formals {
+            formals: Vec::new(),
+            ellipsis: false,
+            alias: None,
+        }) else {
+            panic!()
+        };
+        *alias = Some(sym);
+    }
 }
 
 impl PartialEq for Func {