- var_dump: documentation ( source)
- preg_match: documentation ( source)
<?php
$regex = '%\A/(?<directory_prefix>lf|im)/(?<rule>[a-z-_^\d]+)/(?<ire_id>[0-9a-z]+(~\w{6})?)_(?<sty_id>\d+).(?<extension>jpg|gif|png|webp)\Z%i';
$string = '/lf/234/hash/30593/31985724/1/custom_image.png';
$result = preg_match($regex, $string, $matches);
var_dump($regex);
var_dump($string);
var_dump($result);
var_dump($matches);