diff options
| author | Bruce Hill <bruce@bruce-hill.com> | 2024-11-17 13:25:32 -0500 |
|---|---|---|
| committer | Bruce Hill <bruce@bruce-hill.com> | 2024-11-17 13:25:32 -0500 |
| commit | b51cd728c63227fbe9d5650096d07021f808ca8c (patch) | |
| tree | dba1b848c25fb6f11597c6442709091994bb4b0f | |
| parent | 3edbba7032bdef40fe7661d9fc9d82dee79f0240 (diff) | |
Add 'unless' as an alias for 'if not'
| -rw-r--r-- | parse.c | 37 |
1 files changed, 27 insertions, 10 deletions
@@ -51,7 +51,7 @@ int op_tightness[] = { }; static const char *keywords[] = { - "yes", "xor", "while", "when", "use", "struct", "stop", "skip", "return", + "yes", "xor", "while", "when", "use", "unless", "struct", "stop", "skip", "return", "or", "not", "no", "mod1", "mod", "pass", "lang", "inline", "in", "if", "func", "for", "extern", "enum", "else", "do", "defer", "and", "_min_", "_max_", NULL, @@ -1008,7 +1008,7 @@ ast_t *parse_index_suffix(parse_ctx_t *ctx, ast_t *lhs) { } ast_t *parse_comprehension_suffix(parse_ctx_t *ctx, ast_t *expr) { - // <expr> for [<index>,]<var> in <iter> [if <condition>] + // <expr> "for" [<index>,]<var> "in" <iter> ["if" <condition> | "unless" <condition>] if (!expr) return NULL; const char *start = expr->start; const char *pos = expr->end; @@ -1035,34 +1035,51 @@ ast_t *parse_comprehension_suffix(parse_ctx_t *ctx, ast_t *expr) { if (match_word(&next_pos, "if")) { pos = next_pos; filter = expect(ctx, pos-2, &pos, parse_expr, "I expected a condition for this 'if'"); + } else if (match_word(&next_pos, "unless")) { + pos = next_pos; + filter = expect(ctx, pos-2, &pos, parse_expr, "I expected a condition for this 'unless'"); + filter = WrapAST(filter, Not, filter); } return NewAST(ctx->file, start, pos, Comprehension, .expr=expr, .vars=vars, .iter=iter, .filter=filter); } ast_t *parse_optional_conditional_suffix(parse_ctx_t *ctx, ast_t *stmt) { - // <statement> if <condition> + // <statement> "if" <condition> | <statement> "unless" <condition> if (!stmt) return stmt; const char *start = stmt->start; const char *pos = stmt->end; - if (!match_word(&pos, "if")) + if (match_word(&pos, "if")) { + ast_t *condition = expect(ctx, pos-2, &pos, parse_expr, "I expected a condition for this 'if'"); + return NewAST(ctx->file, start, pos, If, .condition=condition, .body=stmt); + } else if (match_word(&pos, "unless")) { + ast_t *condition = expect(ctx, pos-2, &pos, parse_expr, "I expected a condition for this 'unless'"); + condition = WrapAST(condition, Not, condition); + return NewAST(ctx->file, start, pos, If, .condition=condition, .body=stmt); + } else { return stmt; - - ast_t *condition = expect(ctx, pos-2, &pos, parse_expr, "I expected a condition for this 'if'"); - return NewAST(ctx->file, start, pos, If, .condition=condition, .body=stmt); + } } PARSER(parse_if) { - // if <condition> <body> [else <body>] + // "if" <condition> <body> ["else" <body>] | "unless" <condition> <body> ["else" <body>] const char *start = pos; int64_t starting_indent = get_indent(ctx, pos); - if (!match_word(&pos, "if")) + bool unless; + if (match_word(&pos, "if")) + unless = false; + else if (match_word(&pos, "unless")) + unless = true; + else return NULL; - ast_t *condition = optional(ctx, &pos, parse_declaration); + ast_t *condition = unless ? NULL : optional(ctx, &pos, parse_declaration); if (!condition) condition = expect(ctx, start, &pos, parse_expr, "I expected to find a condition for this 'if'"); + if (unless) + condition = WrapAST(condition, Not, condition); + ast_t *body = expect(ctx, start, &pos, parse_block, "I expected a body for this 'if' statement"); const char *tmp = pos; |