code: JCExpression argumentsOpt(List<JCExpression> typeArgs, JCExpression t) {
          if ((mode & EXPR) != 0 && token.kind == LPAREN || typeArgs != null) {
              mode = EXPR;
              return arguments(typeArgs, t);
          } else {
              return t;
          }
      }
docs: ArgumentsOpt = [ Arguments ]