3v4l.org

run code in 300+ PHP versions simultaneously
<?php $string = <<<STRING Fig. 1. sasasa Fig. 34. 345 dffdfd etc. dsds STRING; echo preg_replace('~Fig\.\K (\d+\.) ~', '&nbsp;$1&nbsp;', $string);
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
Fig.&nbsp;1.&nbsp;sasasa Fig.&nbsp;34.&nbsp;345 dffdfd etc. dsds
preferences:
76.23 ms | 407 KiB | 5 Q