feat: add ReDef.t_spec

crates/erg_compiler/context/initialize/classes.rs

@@ -897,7 +897,7 @@ impl Context {
             Str,
             vec![kw(KW_PAT, Str), kw(KW_INTO, Str)],
             None,
-            vec![],
+            vec![kw(KW_COUNT, Int)],
             None,
             Str,
         );

crates/erg_compiler/context/initialize/mod.rs

@@ -744,6 +744,7 @@ const KW_EPSILON: &str = "epsilon";
 const KW_PATH: &str = "Path";
 const KW_NDIGITS: &str = "ndigits";
 const KW_BYTES_OR_BUFFER: &str = "bytes_or_buffer";
+const KW_COUNT: &str = "count";
 
 pub fn builtins_path() -> PathBuf {
     erg_pystd_path().join("builtins.d.er")

crates/erg_parser/ast.rs

@@ -5725,6 +5725,7 @@ impl Def {
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct ReDef {
     pub attr: Accessor,
+    pub t_spec: Option<TypeSpecWithOp>,
     pub expr: Box<Expr>,
 }
 
@@ -5742,9 +5743,10 @@ impl_locational!(ReDef, attr, expr);
 #[pymethods]
 impl ReDef {
     #[staticmethod]
-    pub fn new(attr: Accessor, expr: Expr) -> Self {
+    pub fn new(attr: Accessor, t_spec: Option<TypeSpecWithOp>, expr: Expr) -> Self {
         Self {
             attr,
+            t_spec,
             expr: Box::new(expr),
         }
     }

crates/erg_parser/desugar.rs

@@ -332,10 +332,13 @@ impl Desugarer {
                     .collect();
                 Expr::PatchDef(PatchDef::new(def, methods))
             }
-            Expr::ReDef(redef) => {
+            Expr::ReDef(mut redef) => {
                 let expr = desugar(*redef.expr);
+                if let Some(t_op) = &mut redef.t_spec {
+                    *t_op.t_spec_as_expr = desugar(*t_op.t_spec_as_expr.clone());
+                }
                 let attr = Self::perform_desugar_acc(desugar, redef.attr);
-                Expr::ReDef(ReDef::new(attr, expr))
+                Expr::ReDef(ReDef::new(attr, redef.t_spec, expr))
             }
             Expr::Lambda(mut lambda) => {
                 let mut chunks = vec![];