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Subject: Re: [PHP-DEV] Re: new overloading feature?
From: ondrej@kmit.sk (=?UTF-8?B?T25kcmVqIEl2YW5pxI0=?=)

Lukas Smith wrote:
> So please explain to me how you would write a singleton static method
> for a base class from which you can inherite. Suddenly the idea with
> using the class name becomes less useful.

IMHO, you need singleton factory :)

Inheritance is very strong relationship between classes. For example I
have base class 'Animal' and derived classes 'Dog' and 'Cat'. I can find
similarity between 'Dog' and 'Cat'. (They are animals)

If I have base class Singleton and derived classes 'MyCar' and 'MyCat'.
I can't find similarity between this classes.

Solutions is:

class SingletonFactory {
	private $instances;

	__construct() {
		$this->instances = array();
	}

	function getInstance($name) {
		if(is_a($this->instances[$name], $name) === false) {
			$this->instances[$name] = new $name;
		}
		
		return $this->instances[$name];
	}
}

FYI: SingletonFactory can be a pure static class.

-- 
Ondrej Ivanic
(ondrej@kmit.sk)