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run code in 200+ php & hhvm versions
<?php $arr = ['foo' => ['bar' => 'baz']]; ['foo' => &$foo] = $arr; $foo = ['baz' => 'qux']; print_r($arr); // ['foo' => ['baz' => 'qux']];
Output for 7.3.0
Array ( [foo] => Array ( [baz] => qux ) )
Output for 7.1.25 - 7.2.13
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.