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<?php $a = array('a' => 'a', 'b' => 'b', 'z' => array('c' => 'c', 'd' => 'd')); $b = array('a' => 'c', 'z' => array('c' => 'e')); $merge = function($a, $b) use ($merge){ if (is_array($a) && is_array($b)){ foreach ($b as $key => $value){ if (is_array($value) && isset($a[$key]) && is_array($a[$key])){ return $merge($a[$key], $value); } else { return $value; } } } else { return $b; } }; var_dump($merge($a, $b));
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: Undefined variable $merge in /in/Xv6Op on line 5 string(1) "c"
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.25, 7.4.27 - 7.4.33
Notice: Undefined variable: merge in /in/Xv6Op on line 5 string(1) "c"
Output for 7.3.32 - 7.3.33, 7.4.26
string(1) "c"
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/Xv6Op on line 5
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected T_FUNCTION in /in/Xv6Op on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/Xv6Op on line 5
Process exited with code 255.

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