As similar thing [to Javascript object literals] can be done in PHP using anonymous functions (since 5.3) [...] Since version 5.3 Php added support for closures and that feature has been used above to create javascript style object literals. The use(&$a) expression makes the variable $a available inside the function happy.

Code snippets are included showing how to create these objects via the use of closures and a little trickery with call_user_func_array and __call to make assigning properties easier.

I was looking at the way view helpers work in ZF2 and thought it would be more convenient if we altered the syntax a little. A side-effect of the change was that we'd have to use call_user_func_array, which is perceived as slow. I thought I'd whip up a simple test to find out how much slower it would be over a direct method call.

He includes the sample code he used to benchmark the request times between the two versions measured by microtime. In his results he saw a difference of almost five seconds between the same code running on 5.3 versus 5.2 (according to test runs on his laptop).