3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $subject = 'http://distilleryimage3_s3_amazonaws_com/_8af11cdcf11e286b022000ae90285_7_jpg'; $pattern = '/(_)(?!\d_jpg)/'; var_dump(preg_replace($pattern, '.\2', $subject));
Output for 4.3.0 - 7.2.0
string(77) "http://distilleryimage3.s3.amazonaws.com/.8af11cdcf11e286b022000ae90285_7.jpg"