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<?php $r = [ '123' => "1", 'W' => "123", ]; var_dump($r); print_r($r['W']); $r['W'] = '999'; var_dump($r); print_r($r['W']);
Output for 5.6.38 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
array(2) { [123]=> string(1) "1" ["W"]=> string(3) "123" } Notice: Undefined index: W in /in/oWS6G on line 9 array(3) { [123]=> string(1) "1" ["W"]=> string(3) "123" ["W"]=> string(3) "999" } 999
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.34, 8.3.0 - 8.3.35, 8.4.1 - 8.4.26, 8.5.0 - 8.5.11
array(2) { [123]=> string(1) "1" ["W"]=> string(3) "123" } Warning: Undefined array key "W" in /in/oWS6G on line 9 array(3) { [123]=> string(1) "1" ["W"]=> string(3) "123" ["W"]=> string(3) "999" } 999
Output for 7.3.32 - 7.3.33
array(2) { [123]=> string(1) "1" ["W"]=> string(3) "123" } array(3) { [123]=> string(1) "1" ["W"]=> string(3) "123" ["W"]=> string(3) "999" } 999
preferences:
35.33 ms | 1147 KiB | 13 Q