PHP singleton pattern - question about extends

Question

Just a quick question. I understand that Singleton patterns can be extended and that inheritance is applied. I was just wondering if I called a base class and then a extended class is there additional overhead than if I just called the extended class by itself?

Answer 1

If what you're talking about is something like

class BaseSingleton {
    public function DoSomething() {
    }
}

class ExtendedSingleton extends BaseSingleton {
    public function DoSomething() {
        parent::DoSomething();
    }
}

then yes, there is overhead in the call being forwarded from the child class's DoSomething() to the parent class's. If ExtendedSingleton does not redefine DoSomething() , though, there is no additional overhead.