Description:
------------
---
From manual page: https://php.net/language.constants.predefined
From manual page: https://php.net/functions.anonymous
---

__FUNCTION__ seems to correctly refer to an anonymous function within itself, but there's no information on either of the above pages. Based on internet searches it wasn't always the case, but I couldn't find the changelog where it was fixed.

Does it not work 100% of the time? Is there some reason it's not officially documented?

Test script:
---------------
<?php
call_user_func(function() {
    var_dump(__FUNCTION__);
});


Actual result:
--------------
/path/to/closure-test.php:3:string '{closure}' (length=9)