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run code in 300+ PHP versions simultaneously
<?php $strings = [ "This is a word", "<-#word#->", "<-#<-#<-#word#->#->#->", ]; $p = "word"; foreach ($strings as $string) { $string = preg_replace("/(?<!<-#)($p)(?!#->)/i", '<-#$1#->', $string); echo $string . PHP_EOL; }
Output for 7.1.25 - 7.1.28, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
This is a <-#word#-> <-#word#-> <-#<-#<-#word#->#->#->
preferences:
163.84 ms | 403 KiB | 162 Q