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<?php $a = [1,2,3,4,5,6,7,8,9]; foreach ($a as $key => $value) { if ($key === 4) { break; } } var_dump(key($a));
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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
int(0)
Output for 5.4.8 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
int(5)

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206.23 ms | 402 KiB | 235 Q