PHP array_walk require_once

Question

I was just wondering if anyone knew why I can't use require_once as a callback for array_walk. I can just include it in an anonymous function and run that, but it gives an invalid callback error for the usage:

$includes = array(
    'file1.php',
    'file2.php',
    'file3.php'
);
array_walk($includes, 'require_once');

Answer 1

You are going to waste more time finding out what's wrong. Just use:

$includes = [
    'file1.php',
    'file2.php',
    'file3.php'
];
foreach($includes as $include) {
    require_once($include);
}

Answer 2

require_once is not a PHP function, but a control structure.