private int resolveParameter(@Nullable LighterASTNode expr) {
    if (expr != null && expr.getTokenType() == REFERENCE_EXPRESSION && findExpressionChild(myTree, expr) == null) {
      String name = getNameIdentifierText(myTree, expr);
      if (name == null) return -1;

      List<LighterASTNode> parameters = getParameters();
      for (int i = 0; i < parameters.size(); i++) {
        if (name.equals(getNameIdentifierText(myTree, parameters.get(i)))) {
          return i;
        }
      }
    }
    return -1;
  }
private int resolveParameter(@Nullable LighterASTNode expr)