<?php

trait Singleton {

  private static $instance = null;

  public static function Instance() {
    return is_null(self::$instance) ? self::$instance = new self : self::$instance;
  }

}


interface ISingleton {
  public static function Instance();
}


class CMySingleton implements ISingleton {

  use Singleton;

}

$n =CMySingleton::Instance();