Fix #72

compiler/erg_compiler/context/register.rs

@@ -25,11 +25,11 @@ use Visibility::*;
 
 impl Context {
     /// If it is a constant that is defined, there must be no variable of the same name defined across all scopes
-    fn registered(&self, name: &Str, is_const: bool) -> bool {
+    pub(crate) fn registered(&self, name: &str, is_const: bool) -> bool {
         if self.params.iter().any(|(maybe_name, _)| {
             maybe_name
                 .as_ref()
-                .map(|n| n.inspect() == name)
+                .map(|n| &n.inspect()[..] == name)
                 .unwrap_or(false)
         }) || self.locals.contains_key(name)
         {
@@ -87,7 +87,7 @@ impl Context {
         let muty = Mutability::from(&name[..]);
         let kind = id.map_or(VarKind::Declared, VarKind::Defined);
         if self.registered(name, sig.is_const()) {
-            return Err(TyCheckError::duplicate_decl_error(
+            return Err(TyCheckError::reassign_error(
                 line!() as usize,
                 sig.loc(),
                 self.caused_by(),
@@ -136,14 +136,6 @@ impl Context {
         self.validate_var_sig_t(ident, sig.t_spec.as_ref(), body_t, Normal)?;
         let muty = Mutability::from(&ident.inspect()[..]);
         let generalized = self.generalize_t(body_t.clone());
-        if self.registered(ident.inspect(), ident.is_const()) {
-            Err(TyCheckError::reassign_error(
-                line!() as usize,
-                ident.loc(),
-                self.caused_by(),
-                ident.inspect(),
-            ))
-        } else {
         if self.decls.remove(ident.inspect()).is_some() {
             // something to do?
         }
@@ -152,7 +144,6 @@ impl Context {
         self.locals.insert(ident.name.clone(), vi);
         Ok(())
     }
-    }
 
     /// 宣言が既にある場合、opt_decl_tに宣言の型を渡す
     fn assign_param(
@@ -370,14 +361,6 @@ impl Context {
                     )
                 })?;
         }
-        if self.registered(name.inspect(), name.is_const()) {
-            Err(TyCheckError::reassign_error(
-                line!() as usize,
-                name.loc(),
-                self.caused_by(),
-                name.inspect(),
-            ))
-        } else {
         let sub_t = if sig.ident.is_procedural() {
             proc(
                 non_default_params.clone(),
@@ -435,7 +418,6 @@ impl Context {
         self.locals.insert(name.clone(), vi);
         Ok(())
     }
-    }
 
     // To allow forward references and recursive definitions
     pub(crate) fn preregister(&mut self, block: &ast::Block) -> TyCheckResult<()> {

compiler/erg_compiler/error.rs

@@ -685,10 +685,10 @@ impl TyCheckError {
                 AssignError,
                 loc,
                 switch_lang!(
-                    "japanese" => format!("変数{name}に再代入されています"),
-                    "simplified_chinese" => format!("不能为变量{name}分配两次"),
-                    "traditional_chinese" => format!("不能為變量{name}分配兩次"),
-                    "english" => format!("cannot assign twice to the variable {name}"),
+                    "japanese" => format!("変数{YELLOW}{name}{RESET}に再代入されています"),
+                    "simplified_chinese" => format!("不能为变量{YELLOW}{name}{RESET}分配两次"),
+                    "traditional_chinese" => format!("不能為變量{YELLOW}{name}{RESET}分配兩次"),
+                    "english" => format!("cannot assign twice to the variable {YELLOW}{name}{RESET}"),
                 ),
                 None,
             ),

compiler/erg_compiler/lower.rs

@@ -577,6 +577,14 @@ impl ASTLowerer {
             } else {
                 "<lambda>"
             };
+            if self.ctx.registered(name, def.sig.is_const()) {
+                return Err(LowerError::reassign_error(
+                    line!() as usize,
+                    def.sig.loc(),
+                    self.ctx.caused_by(),
+                    name,
+                ));
+            }
             self.ctx.grow(name, ContextKind::Instant, def.sig.vis())?;
             let res = match def.sig {
                 ast::Signature::Subr(sig) => self.lower_subr_def(sig, def.body),