_varList[i].evalAssign(env, value.get(_keyList[i]));
_varList[i].evalAssign(env, value.get(_keyList[i]).copy());
  public Value eval(Env env)    throws Throwable  {    Value value = _value.eval(env);    int len = _varList.length;        for (int i = 0; i < len; i++) {      if (_varList[i] != null)	_varList[i].evalAssign(env, value.get(_keyList[i]));    }        return value;  }