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run code in 300+ PHP versions simultaneously
<?php $str = <<<STR one blah two blah foo blah three blah foo blah four blah five blah foo blah STR; $regex = "~(?<=^|\n)foo[\n]*(?:\n|$)~"; echo preg_replace($regex, '', $str, -1, $count), "\n"; echo "$count\n";
Output for 5.1.3 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
one blah two blah foo blah three blah foo blah four blah five blah foo blah 0
Output for 5.1.2
Notice: Undefined variable: count in /in/M7cF7 on line 17 one blah two blah foo blah three blah foo blah four blah five blah foo blah Notice: Undefined variable: count in /in/M7cF7 on line 18
Output for 5.1.0 - 5.1.1
Notice: Undefined variable: count in /in/M7cF7 on line 16 one blah two blah foo blah three blah foo blah four blah five blah foo blah Notice: Undefined variable: count in /in/M7cF7 on line 17
Output for 5.0.4 - 5.0.5
Notice: Undefined variable: count in /in/M7cF7 on line 16 Warning: Wrong parameter count for preg_replace() in /in/M7cF7 on line 16 Notice: Undefined variable: count in /in/M7cF7 on line 17
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.1, 4.4.3 - 4.4.9, 5.0.0 - 5.0.3
Notice: Undefined variable: count in /in/M7cF7 on line 16 Warning: Wrong parameter count for preg_replace() in /in/M7cF7 on line 16 Notice: Undefined variable: count in /in/M7cF7 on line 17
Output for 4.4.2
Notice: Undefined variable: count in /in/M7cF7 on line 17 Warning: Wrong parameter count for preg_replace() in /in/M7cF7 on line 17 Notice: Undefined variable: count in /in/M7cF7 on line 18
preferences:
230.28 ms | 402 KiB | 357 Q