code: private String getParameterJSDocType(List<JSType> types, int index, int minArgs, int maxArgs) {
      JSType type = types.get(index);
      if (index < minArgs) {
        return type.toAnnotationString(Nullability.EXPLICIT);
      }
      boolean isRestArgument = maxArgs == Integer.MAX_VALUE && index == types.size() - 1;
      if (isRestArgument) {
        return "..." + restrictByUndefined(type).toAnnotationString(Nullability.EXPLICIT);
      }
      return restrictByUndefined(type).toAnnotationString(Nullability.EXPLICIT) + "=";
    }
docs: Creates a JSDoc-suitable String representation of the type of a parameter.