feat: 枚举关联数据 ADT — enum Option { Some(i64), None }

src/parser/parser.c

@@ -187,15 +187,21 @@ static AstNode* parse_struct_init(Parser* p, const Token* name, ErrorInfo* error
 static AstNode* parse_ident_or_call(Parser* p, ErrorInfo* error) {
     const Token* name = advance(p);
 
-    // 枚举变体引用: Name::Variant
+    // 枚举变体引用: Name::Variant 或 Name::Variant(payload)
     if (peek(p)->kind == TOK_COLON_COLON) {
         advance(p); // 跳过 ::
         const Token* variant = expect(p, TOK_IDENT, error, "枚举变体名");
         if (!variant) return NULL;
+        AstNode* payload = NULL;
+        if (match(p, TOK_LPAREN)) {
+            payload = parse_expr(p, error);
+            if (!payload) return NULL;
+            if (!expect(p, TOK_RPAREN, error, "缺少 ')'")) return NULL;
+        }
         return ast_make_enum_variant(p->arena,
             arena_strdup_impl(p->arena, name->start, name->length),
             arena_strdup_impl(p->arena, variant->start, variant->length),
-            tok_loc(name));
+            payload, tok_loc(name));
     }
 
     // 结构体初始化: Name { field: val, ... }
@@ -898,18 +904,39 @@ AstNode* parse(Arena* a, const Token* tokens, size_t count,
             const Token* name = expect(&p, TOK_IDENT, error, "enum 后应为枚举名");
             if (!name) return NULL;
             if (!expect(&p, TOK_LBRACE, error, "缺少 '{'")) return NULL;
-            const char* variants[64]; int vcount = 0;
+            const char* variants[64];
+            TypeKind payload_types[64];
+            const char* payload_snames[64];
+            int vcount = 0;
             while (peek(&p)->kind != TOK_RBRACE && !error->message) {
                 if (vcount >= 64) { error->message = "枚举变体过多(最多64)"; error->filename = p.filename; error->line = peek(&p)->line; error->col = peek(&p)->col; return NULL; }
                 const Token* vname = expect(&p, TOK_IDENT, error, "变体名");
                 if (!vname) return NULL;
-                variants[vcount++] = arena_strdup_impl(p.arena, vname->start, vname->length);
+                variants[vcount] = arena_strdup_impl(p.arena, vname->start, vname->length);
+                payload_types[vcount] = TYPE_VOID;
+                payload_snames[vcount] = NULL;
+                // 可选 payload: Variant(Type)
+                if (peek(&p)->kind == TOK_LPAREN) {
+                    advance(&p);
+                    TypeInfo pti = parse_type_expr(&p, error);
+                    if (pti.kind == TYPE_ERROR) return NULL;
+                    payload_types[vcount] = pti.kind;
+                    payload_snames[vcount] = pti.struct_name;
+                    if (!expect(&p, TOK_RPAREN, error, "缺少 ')'")) return NULL;
+                }
+                vcount++;
                 if (peek(&p)->kind == TOK_COMMA) advance(&p); else break;
             }
             if (!expect(&p, TOK_RBRACE, error, "缺少 '}'")) return NULL;
             const char** v_arr = arena_alloc_impl(p.arena, vcount * sizeof(const char*));
             memcpy(v_arr, variants, vcount * sizeof(const char*));
-            AstNode* enum_decl = ast_make_enum_decl(p.arena, arena_strdup_impl(p.arena, name->start, name->length), v_arr, vcount, tok_loc(name));
+            TypeKind* pt_arr = arena_alloc_impl(p.arena, vcount * sizeof(TypeKind));
+            memcpy(pt_arr, payload_types, vcount * sizeof(TypeKind));
+            const char** ps_arr = arena_alloc_impl(p.arena, vcount * sizeof(const char*));
+            memcpy(ps_arr, payload_snames, vcount * sizeof(const char*));
+            AstNode* enum_decl = ast_make_enum_decl(p.arena,
+                arena_strdup_impl(p.arena, name->start, name->length),
+                v_arr, pt_arr, ps_arr, vcount, tok_loc(name));
             if (enum_count >= 64) { error->message = "枚举过多 (最多64)"; error->filename = p.filename; error->line = peek(&p)->line; error->col = peek(&p)->col; return NULL; }
             enums[enum_count++] = enum_decl;
         } else if (peek(&p)->kind == TOK_EXTEND) {