At-ease

at-ease is a PHP library that provides a safe alternative to PHP's error control operator. From 2010 to 2020, it was recommended not to use in MediaWiki and extensions, but instead use this library. The code was originally introduced to MediaWiki in r4261, and then split out into a separate library during the development cycle.

Since 2020 and the better support of fatal error handling in PHP 7, it is recommended to use  in MediaWiki and extensions: see the "Error handling" section on the PHP coding conventions page.