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<?php preg_match("/^(?<NAME_A>aaa)(?:(?<NAME_B>x)?)/", "aaay", $matches, PREG_UNMATCHED_AS_NULL); var_dump($matches);
Output for 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.31, 8.2.0 - 8.2.28, 8.3.0 - 8.3.19, 8.4.1 - 8.4.5
array(5) { [0]=> string(3) "aaa" ["NAME_A"]=> string(3) "aaa" [1]=> string(3) "aaa" ["NAME_B"]=> NULL [2]=> NULL }
Output for 7.2.0 - 7.2.33, 7.3.16 - 7.3.33
array(3) { [0]=> string(3) "aaa" ["NAME_A"]=> string(3) "aaa" [1]=> string(3) "aaa" }
Output for 7.1.0 - 7.1.20
Notice: Use of undefined constant PREG_UNMATCHED_AS_NULL - assumed 'PREG_UNMATCHED_AS_NULL' in /in/em6fi on line 3 Warning: preg_match() expects parameter 4 to be integer, string given in /in/em6fi on line 3 NULL
preferences:
152.32 ms | 409 KiB | 5 Q