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run code in 300+ PHP versions simultaneously
<?php $pattern = []; for ($i = 0; $i < 300; $i++) { $pattern[] = "(?'group{$i}'{$i}$)"; } $fullPattern = '/' . implode('|', $pattern) . '/uix'; preg_match($fullPattern, '290', $matches); var_dump(isset($matches['group253'])); var_dump(isset($matches['group254'])); var_dump(isset($matches['group255'])); var_dump($matches['group290']); var_dump($matches['group291']);
Output for 8.0.0 - 8.0.3
bool(true) bool(true) bool(true) string(3) "290" Warning: Undefined array key "group291" in /in/sJWmA on line 15 NULL
Output for 5.6.25, 7.0.10 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.27, 7.4.0 - 7.4.16
bool(true) bool(true) bool(true) string(3) "290" Notice: Undefined index: group291 in /in/sJWmA on line 15 NULL
Output for 5.6.0 - 5.6.24, 7.0.0 - 7.0.9
bool(true) bool(false) bool(true) string(0) "" string(3) "290"