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<?php $a = [1,2,3,4]; foreach($a as &$num) {} echo implode(',',$a).PHP_EOL; // 1,2,3 var_dump($a); foreach($a as $num) {echo $num;} var_dump($num); var_dump($a); echo implode(',',$a).PHP_EOL; // 1,2,2
Output for 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
1,2,3,4 array(4) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> &int(4) } 1233int(3) array(4) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> &int(3) } 1,2,3,3

preferences:
153.03 ms | 403 KiB | 159 Q