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<?php $arr = ['foo' => ['bar' => 'baz']]; ['foo' => &$foo] = $arr; $foo = ['baz' => 'qux']; print_r($arr); // ['foo' => ['baz' => 'qux']];
Output for 7.3.0 - 7.3.33, 7.4.4 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.13
Array ( [foo] => Array ( [baz] => qux ) )
Output for 7.1.25, 7.2.0 - 7.2.33
Fatal error: [] and list() assignments cannot be by reference in /in/30suM on line 4
Process exited with code 255.
Output for 5.6.38, 7.0.33
Parse error: syntax error, unexpected '=' in /in/30suM on line 4
Process exited with code 255.
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88.2 ms | 408 KiB | 5 Q