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<?php $string = '--'; $doesNotMatchInPhp7 = '/(?|(---)|(-))\1$/'; $matchesInPhp7 = '/(?|(-)|(---))\1$/'; var_dump(preg_match($doesNotMatchInPhp7, $string)); var_dump(preg_match($matchesInPhp7, $string));
Output for 5.6.0 - 5.6.40, 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 - 8.2.19, 8.3.0 - 8.3.7
int(1) int(1)
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33
int(0) int(1)
preferences:
239.24 ms | 402 KiB | 292 Q