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<?php function myCallback($key, $val) { var_dump("myCallback - key: $key, val: $val"); return $val * 2; } function foreachMap($callback, $givenArray) { $result = []; foreach ($givenArray as $key=>$val) { $result[$key] = $callback($key, $val); } return $result; } $values = array(4, 6, 3); $mapped = foreachMap('myCallback', $values); var_dump($mapped);
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
string(27) "myCallback - key: 0, val: 4" string(27) "myCallback - key: 1, val: 6" string(27) "myCallback - key: 2, val: 3" array(3) { [0]=> int(8) [1]=> int(12) [2]=> int(6) }

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