ArrayValue newArray = new ArrayValueImpl();
ArrayValue newArray = new ArrayValueImpl(array.getSize());
  public Value array_keys(Env env, ArrayValue array,                          @Optional Value searchValue,                          @Optional boolean isStrict)    throws Throwable  {    if (array == null)      return NullValue.NULL;    ArrayValue newArray = new ArrayValueImpl();    for (Map.Entry<Value, Value> entry : array.entrySet()) {      Value entryValue = entry.getValue();      Value entryKey = entry.getKey();      if (searchValue == null || searchValue instanceof DefaultValue)        newArray.put(entryKey);      else if (entryValue.eq(searchValue)      	newArray.put(entryKey);    }    return newArray;  }