Why can't I use 'require' with 'array_map'?

Question

I've tried to include the contents from a list of files:

$files = [
    'a.php',
    'b.php',
];
$contents = array_map('require', $files);

But this didn't work. The error I get is:

Warning: array_map() expects parameter 1 to be a valid callback, function 'require' not found or invalid function name

Why is this and is there a way to make it work?

Answer 1

Because require isn't a function, it's a language construct.

You'll need to create a valid callback function to do the actual require, or use an autoloader

Answer 2

As everyone already noticed - it is a language construct.

You can try this

$includes = array('a.php', 'b.php');

array_map(function($file){
        require $file;
}, $includes);