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<?php $input = array( array( 'tag_name' => array('google', 'Yahoo') ), array( 'tag_name' => array('technology', 'andsuch') ) ); echo implode(', ', array_walk(function ($entry) { return $entry['tag_name']; }, $input));
Output for 8.3.0 - 8.3.6
Fatal error: Uncaught Error: array_walk(): Argument #1 ($array) could not be passed by reference in /in/HGVLp:13 Stack trace: #0 {main} thrown in /in/HGVLp on line 13
Process exited with code 255.
Output for 8.1.23 - 8.1.28, 8.2.10 - 8.2.18
Fatal error: Uncaught Error: array_walk(): Argument #1 ($array) cannot be passed by reference in /in/HGVLp:13 Stack trace: #0 {main} thrown in /in/HGVLp on line 13
Process exited with code 255.
Output for 5.3.0 - 5.3.28, 5.4.0 - 5.4.29
Fatal error: Only variables can be passed by reference in /in/HGVLp on line 13
Process exited with code 255.
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