function /w preceding ampersand

[saf]

Hi

I recently came across a function in one of the php books and didn't have a clue as to why someone would use an ampersand before a function name.

[code]
function &test($var){
  $result = $var+1;
  return $result;
}
[/code]

Can anyone explain what the purpose of the ampersand (&) is (I'd prefer an example of it)?

Thanks,
Saf

[trq]

You will want to read the manuals section on [url=http://www.php.net/manual/en/language.references.php]references[/url].