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<?php function b(&$v) { $v = 0; } $ar = [[1, 2, 3, 4], [1, 2, 3, 4]]; foreach ($ar as &$v) { foreach ($v as $v1) { b($v1); } } unset($v); var_dump($ar);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 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 - 8.3.7
array(2) { [0]=> array(4) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) } [1]=> array(4) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) } }
preferences:
194.32 ms | 404 KiB | 174 Q