3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = array(); $v = 'before'; $arr[][$v = 'after'] = $v; $v = 'before'; $arr[][$v] = $v = 'after'; $v = 'before'; $arr[][$v . ''] = $v = 'after'; var_export($arr);
Output for 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.30, 7.0.0 - 7.0.29, 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 - 8.1.31, 8.2.0 - 8.2.26, 8.3.0 - 8.3.15, 8.4.1 - 8.4.2
array ( 0 => array ( 'after' => 'after', ), 1 => array ( 'after' => 'after', ), 2 => array ( 'before' => 'after', ), )
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5
array ( 0 => array ( 'after' => 'after', ), 1 => array ( 'before' => 'after', ), 2 => array ( 'before' => 'after', ), )

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55.05 ms | 407 KiB | 5 Q