gh-51: Ban . from identifiers.

Author: python-processing-unit

src/lexer.c

@@ -242,6 +242,7 @@ Token lexer_next_token(Lexer* lexer) {
         if (c == ':') { advance(lexer); return make_token(lexer, TOKEN_COLON, ":", 1); }
         if (c == '@') { advance(lexer); return make_token(lexer, TOKEN_AT, "@", 1); }
         if (c == '*') { advance(lexer); return make_token(lexer, TOKEN_STAR, "*", 1); }
+        if (c == '.') { advance(lexer); return make_token(lexer, TOKEN_DOT, ".", 1); }
 
         if (c == '"' || c == '\'') {
             return string_token(lexer, c);
@@ -457,7 +458,7 @@ static Token identifier_token(Lexer* lexer) {
 
     while (!is_at_end(lexer)) {
         char c = peek(lexer);
-        if (strchr("abcdefghijklmnopqrstuvwxyz1234567890./ABCDEFGHIJKLMNOPQRSTUVWXYZ$%&~_+|?", c)) {
+        if (strchr("abcdefghijklmnopqrstuvwxyz1234567890/ABCDEFGHIJKLMNOPQRSTUVWXYZ$%&~_+|?", c)) {
             advance(lexer);
             if (len_val + 1 >= capacity) { capacity *= 2; value = safe_realloc(value, capacity); }
             value[len_val++] = c;

src/parser.c

@@ -203,8 +203,30 @@ static Expr* parse_primary(Parser* parser) {
         Stmt* body = parse_block(parser);
         return expr_lambda(params, ret, body, lambda_tok.line, lambda_tok.column);
     }
-    if (match(parser, TOKEN_IDENT)) {
-        return expr_ident(token.literal, token.line, token.column);
+    if (parser->current_token.type == TOKEN_IDENT) {
+        Token idtok = parser->current_token;
+        // Build possibly-dotted identifier by concatenating IDENT (DOT IDENT)*
+        size_t len0 = idtok.literal ? strlen(idtok.literal) : 0;
+        char* name = malloc(len0 + 1);
+        if (!name) { fprintf(stderr, "Out of memory\n"); exit(1); }
+        if (len0) memcpy(name, idtok.literal, len0 + 1); else name[0] = '\0';
+        advance(parser); // consume first IDENT
+        while (parser->current_token.type == TOKEN_DOT && parser->next_token.type == TOKEN_IDENT) {
+            advance(parser); // consume DOT
+            // append '.' + next ident
+            const char* part = parser->current_token.literal ? parser->current_token.literal : "";
+            size_t part_len = strlen(part);
+            size_t cur_len = strlen(name);
+            size_t newlen = cur_len + 1 + part_len + 1;
+            char* tmp = realloc(name, newlen);
+            if (!tmp) { free(name); fprintf(stderr, "Out of memory\n"); exit(1); }
+            name = tmp;
+            name[cur_len] = '.';
+            if (part_len) memcpy(name + cur_len + 1, part, part_len);
+            name[cur_len + 1 + part_len] = '\0';
+            advance(parser); // consume IDENT
+        }
+        return expr_ident(name, idtok.line, idtok.column);
     }
     if (match(parser, TOKEN_LPAREN)) {
         Expr* expr = parse_expression(parser);

src/token.c

@@ -22,6 +22,7 @@ const char* token_type_to_string(PTokenType type) {
         case TOKEN_COLON: return "COLON";
         case TOKEN_AT: return "AT";
         case TOKEN_STAR: return "STAR";
+        case TOKEN_DOT: return "DOT";
         case TOKEN_DASH: return "DASH";
         case TOKEN_TRY: return "TRY";
         case TOKEN_CATCH: return "CATCH";

src/token.h

@@ -29,6 +29,7 @@ typedef enum {
     TOKEN_COLON,    // :
     TOKEN_AT,       // @
     TOKEN_STAR,     // *
+    TOKEN_DOT,      // .
     TOKEN_DASH,     // - (when used as slice range separator)
 
     // Keywords