return  multiUserFunc.UserFunc(aArity);
int arity = LispStandard.InternalListLength(aArguments)-1; return  multiUserFunc.UserFunc(arity);
  public LispUserFunction UserFunction(String aName,int aArity) throws Exception  {    LispMultiUserFunction multiUserFunc = (LispMultiUserFunction)iUserFunctions.LookUp(aName);    if (multiUserFunc != null)    {        return  multiUserFunc.UserFunc(aArity);    }    return null;  }