NYCPHP Meetup

[Dan Cech]

Joseph Crawford wrote:
> also i would like to note that i havent really found a use for that
> singleton pattern shown before in php 4, rather here is another code
> example i posted that will show a better way to use a method to get
> similar results.
> 
> http://www.weberdev.com/get_example-4014.html

You may be better off with something like this:

function &singleton($class) {
     static $instances;

     if (!is_array($instances)) {
         $instances = array();
     }

     if (!isset($instances[$class])) {
         $instances[$class] =& new $class;
     }

     return $instances[$class];
}

This function will correctly manage multiple singleton objects for 
multiple classes, thus:

$mysingle =& singleton('myclass');

$myother =& singleton('anotherclass');

Will both be valid singleton instances of their respective class.  With 
the function in your example the second call to singleton would change 
the object referenced by $mysingle.

I also changed the way the function returns the reference slightly to 
reflect the preferred syntax in php4.

Dan