Value Objects

<?php
class HttpMessage
{
  private int $code;
  private string $response;
  public function __construct(int $code, string $response)
  {
    $this->code     = $code;
    $this->response = $response;
  }
  public function verify(HttpMessage $message) : bool
  {
    return $this->response == $message->response &&
      $this->code == $message->code;
  }
  public function newMessage(int $code, string $response) : HttpMessage
  {
    $newMessage           = clone $this;
    $newMessage->code     = $code;
    $newMessage->response = $response;
    return $newMessage;
  }
}
$ok = new HttpMessage(200, 'OK');
$created = $ok->newMessage(201, 'OK');
echo $ok->verify($created) ?
  'Value objects are equal' :
  'Value objects are not equal';