<?php
$array1 = array('description' => 'desc bla bla bla', 'summary' => 'summary bla bla bla', 'usage' => 'usage bla bla bla');
$array2 = array('description', 'summary');
$array_intersected = array_intersect_ukey($array1, $array2);
var_dump($array_intersected);
Fatal error: Uncaught TypeError: array_intersect_ukey(): Argument #2 must be a valid callback, class "description" not found in /in/RG5Y5:5
Stack trace:
#0 /in/RG5Y5(5): array_intersect_ukey(Array, Array)
#1 {main}
thrown in /in/RG5Y5 on line 5
Process exited with code 255.