- var_dump: documentation ( source)
<?php
$struct = [
'username' => '',
'password' => '',
'someId' => 1,
];
$input = [
'username' => '',
'password' => '',
'someId' => 1,
];
var_dump(arra_diff($struct, $input));
//var_dump(array_diff(array_merge($input, $struct), $struct));