[wp-hackers] anonymous functions for do_action and apply_filters

Nathaniel Taintor goldenapplesdesign at gmail.com
Mon Dec 20 20:49:05 UTC 2010

I think its generally frowned upon, because if you add an anonymous
function, then you have no way of removing it, other than calling

There are also concerns about memory leaks caused by using lambda functions
in php. The add_filter code you cited would create a new function every time
it was called, which may not be a big deal in your case (you're not likely
to trigger the title filter more than 20-50 times in any one page), but
would still be slightly less efficient than defining the function once.

Nathaniel Taintor, Designer/Developer
*Golden Apples Design*

@GoldenApples | 503.877.2880
goldenapplesdesign at gmail.com

On Mon, Dec 20, 2010 at 12:43 PM, Leo germani <leogermani at gmail.com> wrote:

> Hi there,
> have any of you guys discussed about adding the possibility to use php
> anonymous functions [1] with the hooks?
> I mean something like:
> add_filter('the_title', function($title) { return '<b>'. $title. '</b>';
> });
> instead of declaring a function and passing its name as a paramenter to
> add_filter and add_action.
> What you think about it?
> Leo,,
> [1] http://php.net/manual/en/functions.anonymous.php
> --

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