stage1 支持label break, continue

stage1/spl_ast.c

@@ -238,6 +238,7 @@ static int can_start_expr(spl_tok_type_t t) {
     case TOK_IDENT:
     case TOK_AT:
     case TOK_SHARP:
+    case TOK_DOLLAR:
     case TOK_L_PAREN:
     case TOK_L_BRACKET:
     case TOK_L_BRACE:
@@ -1261,6 +1262,40 @@ static spl_ast_node_ref_t parse_prefix(parser_t *p) {
     if (!t)
         return 0;
 
+    if (t->type == TOK_DOLLAR) {
+        spl_ast_node_ref_t label = parse_label(p);
+        const spl_tok_t *kw = peek(p);
+        spl_ast_node_ref_t ref = 0;
+        if (kw && kw->type == KW_WHILE)
+            ref = parse_while_expr(p);
+        else if (kw && kw->type == KW_LOOP)
+            ref = parse_loop_expr(p);
+        else if (kw && kw->type == KW_FOR)
+            ref = parse_for_expr(p);
+        else {
+            SPL_FATAL(kw, "expected while/loop/for after label");
+            return 0;
+        }
+        if (!ref)
+            return 0;
+
+        spl_ast_node_t *n = node_at(p->ast, ref);
+        switch (n->kind) {
+        case SPL_AST_EXPR_WHILE:
+            n->while_expr.label = label;
+            break;
+        case SPL_AST_EXPR_LOOP:
+            n->loop_expr.label = label;
+            break;
+        case SPL_AST_EXPR_FOR:
+            n->for_expr.label = label;
+            break;
+        default:
+            break;
+        }
+        return ref;
+    }
+
     spl_unary_op_t uop;
     switch (t->type) {
     case TOK_SUB:
@@ -1738,8 +1773,6 @@ static spl_ast_node_ref_t parse_while_expr(parser_t *p) {
         return 0;
     advance(p);
 
-    spl_ast_node_ref_t label = parse_label(p);
-
     p->stop_agg++;
     spl_ast_node_ref_t cond = parse_expr(p);
     p->stop_agg--;
@@ -1760,7 +1793,7 @@ static spl_ast_node_ref_t parse_while_expr(parser_t *p) {
     }
 
     spl_ast_node_ref_t ref = new_node(p, SPL_AST_EXPR_WHILE, kw);
-    node_at(p->ast, ref)->while_expr.label = label;
+    node_at(p->ast, ref)->while_expr.label = 0;
     node_at(p->ast, ref)->while_expr.cond = cond;
     node_at(p->ast, ref)->while_expr.body = body;
     node_at(p->ast, ref)->while_expr.else_branch = else_branch;
@@ -1773,11 +1806,10 @@ static spl_ast_node_ref_t parse_loop_expr(parser_t *p) {
         return 0;
     advance(p);
 
-    spl_ast_node_ref_t label = parse_label(p);
     spl_ast_node_ref_t body = parse_block(p);
 
     spl_ast_node_ref_t ref = new_node(p, SPL_AST_EXPR_LOOP, kw);
-    node_at(p->ast, ref)->loop_expr.label = label;
+    node_at(p->ast, ref)->loop_expr.label = 0;
     node_at(p->ast, ref)->loop_expr.body = body;
     return ref;
 }
@@ -1788,9 +1820,6 @@ static spl_ast_node_ref_t parse_for_expr(parser_t *p) {
         return 0;
     advance(p);
 
-    spl_ast_node_ref_t label = parse_label(p);
-
-    // 解析迭代表达式列表（用 stop_as 阻止 'as' 被误解析为类型转换）
     p->stop_as = 1;
     spl_ast_node_ref_vec_t iter_exprs;
     vec_init(iter_exprs);
@@ -1801,7 +1830,6 @@ static spl_ast_node_ref_t parse_for_expr(parser_t *p) {
     }
     p->stop_as = 0;
 
-    // 必须有关键字 as
     const spl_tok_t *t = peek(p);
     if (!t || t->type != KW_AS) {
         SPL_FATAL(t, "expected 'as' in for loop");
@@ -1809,7 +1837,6 @@ static spl_ast_node_ref_t parse_for_expr(parser_t *p) {
     }
     advance(p);
 
-    // 解析绑定变量列表（允许 '_'）
     spl_ast_node_ref_vec_t idents;
     vec_init(idents);
     t = peek(p);
@@ -1835,12 +1862,10 @@ static spl_ast_node_ref_t parse_for_expr(parser_t *p) {
         vec_push(idents, id_node);
     }
 
-    // 循环体必须为块
     spl_ast_node_ref_t body = parse_block(p);
     if (!body)
         return 0;
 
-    // 可选的 else 分支
     spl_ast_node_ref_t else_branch = 0;
     if (peek(p) && peek(p)->type == KW_ELSE) {
         advance(p);
@@ -1852,7 +1877,7 @@ static spl_ast_node_ref_t parse_for_expr(parser_t *p) {
 
     spl_ast_node_ref_t ref = new_node(p, SPL_AST_EXPR_FOR, kw);
     spl_ast_node_t *fe = node_at(p->ast, ref);
-    fe->for_expr.label = label;
+    fe->for_expr.label = 0;
     fe->for_expr.iter_exprs = iter_exprs;
     fe->for_expr.idents = idents;
     fe->for_expr.body = body;
@@ -2153,12 +2178,18 @@ static spl_ast_node_ref_t parse_block(parser_t *p) {
                     SPL_FATAL(t, "only one tail expression allowed");
                 }
                 block->block.tail_expr = expr;
-            } else if (expr && node_at(p->ast, expr)->kind == SPL_AST_EXPR_BLOCK) {
-                vec_push(block->block.stmts, expr);
-                // 继续循环，处理下一个语句
             } else {
-                SPL_FATAL(t, "expected ';' or '}' after expression");
-                break;
+                spl_ast_node_kind_t k = node_at(p->ast, expr)->kind;
+                bool block_like =
+                    (k == SPL_AST_EXPR_BLOCK || k == SPL_AST_EXPR_IF || k == SPL_AST_EXPR_IFVAR ||
+                     k == SPL_AST_EXPR_WHILE || k == SPL_AST_EXPR_LOOP || k == SPL_AST_EXPR_FOR ||
+                     k == SPL_AST_EXPR_MATCH);
+                if (block_like) {
+                    vec_push(block->block.stmts, expr);
+                } else {
+                    SPL_FATAL(t, "expected ';' or '}' after expression");
+                    break;
+                }
             }
         } else {
             SPL_FATAL(t, "unrecognized token in block");