feat: for..in 范围语法 .. 改为 to 关键字

README.md

@@ -98,7 +98,7 @@ graph TB
 
 - `if` / `else` / `else if`
 - `while` 循环
-- `for i in 0..10` (去糖为 while)
+- `for i in 0 to 10` (去糖为 while)
 - `match expr { pat => { ... } _ => { ... } }` (去糖为 if-else)
 - `return`
 

docs/language-reference.md

@@ -188,13 +188,13 @@ while i < 5 {
 ### for 循环
 
 ```rust
-for i in 0..5 {
+for i in 0 to 5 {
     print_i64(i);
 }
 // 输出: 0 1 2 3 4
 ```
 
-`for i in start..end` 等价于 `let mut i = start; while i < end { ...; i += 1; }`
+`for i in start to end` 等价于 `let mut i = start; while i < end { ...; i += 1; }`
 
 ### match
 
@@ -566,7 +566,7 @@ l_lang.exe source.l --emit-ir
 类型:    i64  f64  bool  str  void  struct  enum  [T;N]
 声明:    let x = val          let mut x = val
          let x: Type = val    type Alias = Type
-控制流:  if/else  while  for i in 0..N  match
+控制流:  if/else  while  for i in 0 to N  match
 函数:    fn name(p: T) -> Ret { return expr; }
 结构体:  struct Name { f: Type }   Name { f: val }
 枚举:    enum Name { A, B, C }     Name::B

src/lexer/lexer.c

@@ -58,6 +58,7 @@ static TokenKind check_keyword(const Token* tok) {
     KW("mut",    TOK_MUT);
     KW("if",     TOK_IF);     KW("else",   TOK_ELSE);
     KW("while",  TOK_WHILE);  KW("for",    TOK_FOR);  KW("in",     TOK_IN);
+    KW("to",     TOK_TO);
 	    KW("return", TOK_RETURN);
     KW("i64",    TOK_I64);    KW("f64",    TOK_F64);
     KW("bool",   TOK_BOOL);   KW("str",    TOK_STR);
@@ -137,7 +138,6 @@ Token* lex(Arena* a, const char* source, const char* filename,
         else if (c == '>') { tokens[idx++] = make_token(&l, TOK_GT, l.pos, 1); advance(&l); }
         else if (c == '&' && peek_next(&l) == '&') { tokens[idx++] = make_token(&l, TOK_AND_AND, l.pos, 2); advance(&l); advance(&l); }
         else if (c == '|' && peek_next(&l) == '|') { tokens[idx++] = make_token(&l, TOK_PIPE_PIPE, l.pos, 2); advance(&l); advance(&l); }
-        else if (c == '.' && peek_next(&l) == '.') { tokens[idx++] = make_token(&l, TOK_DOT_DOT, l.pos, 2); advance(&l); advance(&l); }
         else if (c == '.') { tokens[idx++] = make_token(&l, TOK_DOT, l.pos, 1); advance(&l); }
         else if (c == '[') { tokens[idx++] = make_token(&l, TOK_LBRACKET, l.pos, 1); advance(&l); }
         else if (c == ']') { tokens[idx++] = make_token(&l, TOK_RBRACKET, l.pos, 1); advance(&l); }

src/lexer/token.c

@@ -18,7 +18,7 @@ static const char* NAMES[] = {
     [TOK_EQ_EQ] = "==", [TOK_BANG_EQ] = "!=",
     [TOK_LT] = "<", [TOK_GT] = ">", [TOK_LT_EQ] = "<=", [TOK_GT_EQ] = ">=",
     [TOK_AND_AND] = "&&", [TOK_PIPE_PIPE] = "||", [TOK_BANG] = "!",
-    [TOK_ARROW] = "->", [TOK_DOT_DOT] = "..", [TOK_MATCH_ARROW] = "=>",
+    [TOK_ARROW] = "->", [TOK_TO] = "to", [TOK_MATCH_ARROW] = "=>",
     [TOK_PLUS_EQ] = "+=", [TOK_MINUS_EQ] = "-=", [TOK_STAR_EQ] = "*=", [TOK_SLASH_EQ] = "/=",
     [TOK_LPAREN] = "(", [TOK_RPAREN] = ")",
     [TOK_LBRACE] = "{", [TOK_RBRACE] = "}",

src/lexer/token.h

@@ -18,7 +18,7 @@ typedef enum {
     TOK_PLUS, TOK_MINUS, TOK_STAR, TOK_SLASH, TOK_PERCENT,
     TOK_EQ_EQ, TOK_BANG_EQ, TOK_LT, TOK_GT, TOK_LT_EQ, TOK_GT_EQ,
     TOK_AND_AND, TOK_PIPE_PIPE, TOK_BANG,
-    TOK_ARROW, TOK_DOT_DOT, TOK_MATCH_ARROW,
+    TOK_ARROW, TOK_TO, TOK_MATCH_ARROW,
     TOK_PLUS_EQ, TOK_MINUS_EQ, TOK_STAR_EQ, TOK_SLASH_EQ,
     // 分隔符
     TOK_LPAREN, TOK_RPAREN, TOK_LBRACE, TOK_RBRACE,

src/parser/parser.c

@@ -546,8 +546,8 @@ static AstNode* parse_statement(Parser* p, ErrorInfo* error) {
         AstNode* start_expr = parse_expr(p, error);
         if (!start_expr) return NULL;
 
-        // 解析 '..'
+        // 解析 'to'
-        if (!expect(p, TOK_DOT_DOT, error, "缺少 '..'")) return NULL;
+        if (!expect(p, TOK_TO, error, "缺少 'to'")) return NULL;
 
         // 解析结束表达式
         AstNode* end_expr = parse_expr(p, error);
@@ -557,7 +557,7 @@ static AstNode* parse_statement(Parser* p, ErrorInfo* error) {
         AstNode* body = parse_block(p, error);
         if (!body) return NULL;
 
-        // 脱糖: for i in start..end { body; }
+        // 脱糖: for i in start to end { body; }
         //   → { let mut i = start; while i < end { body; i = i + 1; } }
 
         const char* vname = arena_strdup_impl(p->arena, var_name->start, var_name->length);

test/programs/10_for_range.l

@@ -1,5 +1,5 @@
 fn main() -> i64 {
-    for i in 0..5 {
+    for i in 0 to 5 {
         print_i64(i);
     }
     return 0;

test/programs/11_for_step2.l

@@ -1,7 +1,7 @@
 fn main() -> i64 {
     let start: i64 = 10;
     let end: i64 = 15;
-    for n in start..end {
+    for n in start to end {
         print_i64(n);
     }
     return 0;