feat: add null as value token

include/compiler/fzl_token.h

@@ -34,6 +34,7 @@ typedef enum
   FZL_TOKTYPE_STR_LITERAL,  // ""
   FZL_TOKTYPE_NUM_LITERAL,  // 123
   FZL_TOKTYPE_BOOL_LITERAL, // true
+  FZL_TOKTYPE_NULL_LITERAL, // null
 
   FZL_TOKTYPE_DAMPERSAND, // &&
   FZL_TOKTYPE_DVBAR,      // ||

src/compiler/fzl_parser.c

@@ -140,17 +140,10 @@ fzl_node_t *parse_primary(fzl_parser_t *parser)
   if (!parser || !peek(parser))
     return NULL;
 
-  if (is(parser, FZL_TOKTYPE_STR_LITERAL))
-  {
-    fzl_token_t *tok = consume(parser);
-    return fzl_mknode(FZL_NODETYPE_LITERAL, tok);
-  }
-  else if (is(parser, FZL_TOKTYPE_NUM_LITERAL))
-  {
-    fzl_token_t *tok = consume(parser);
-    return fzl_mknode(FZL_NODETYPE_LITERAL, tok);
-  }
-  else if (is(parser, FZL_TOKTYPE_BOOL_LITERAL))
+  if (is(parser, FZL_TOKTYPE_STR_LITERAL) ||
+      is(parser, FZL_TOKTYPE_NUM_LITERAL) ||
+      is(parser, FZL_TOKTYPE_BOOL_LITERAL) ||
+      is(parser, FZL_TOKTYPE_NULL_LITERAL))
   {
     fzl_token_t *tok = consume(parser);
     return fzl_mknode(FZL_NODETYPE_LITERAL, tok);

src/compiler/fzl_reader.c

@@ -88,13 +88,16 @@ fzl_token_t *parse_name(fzl_reader_t *reader)
   else if (strcmp(value, "true") == 0 || strcmp(value, "false") == 0)
     tok = fzl_mktoken(FZL_TOKTYPE_BOOL_LITERAL, l.line, l.col, value, size,
                       l.filename);
+  else if (strcmp(value, "null") == 0)
+    tok = fzl_mktoken(FZL_TOKTYPE_NULL_LITERAL, l.line, l.col, value, size,
+                      l.filename);
   else if (strcmp(value, "str") == 0 || strcmp(value, "char") == 0 ||
            strcmp(value, "bool") == 0 || strcmp(value, "uint") == 0 ||
            strcmp(value, "int") == 0 || strcmp(value, "i8") == 0 ||
            strcmp(value, "i16") == 0 || strcmp(value, "i32") == 0 ||
            strcmp(value, "i64") == 0 || strcmp(value, "u8") == 0 ||
            strcmp(value, "u16") == 0 || strcmp(value, "u32") == 0 ||
-           strcmp(value, "u64") == 0 || strcmp(value, "null") == 0)
+           strcmp(value, "u64") == 0)
     tok = fzl_mktoken(FZL_TOKTYPE_TYPE, l.line, l.col, value, size, l.filename);
   else
     tok = fzl_mktoken(FZL_TOKTYPE_NAME, l.line, l.col, value, size, l.filename);