Pull request for array_filter() improvement

Hi, I found myself wanting a feature of array_filter() with which I can perform filtering based on the array key instead of the value. To scratch this itch, I decided to dive into C again and just add the feature. My proposal is to add a third argument to array_filter() that will send the array keys to the callback. function myfilter($value, $key) { return $key > 4; } array_filter([1, 2, 3, 4, 5, 6, 7], 'myfilter', true); // returns: [6, 7] The pull request can be found here: https://github.com/php/php-src/pull/287 If this is useful for the language as a whole, do let me know what else I should do to champion it. Thanks! -- -- Tjerk