Dynamic array_multisort() without calling deprecated function create_function()

Question

I have this function in my old php5 code that will accept a variable number of parameters and perform sorting based on the parameters:

function array_alternate_multisort(){
    $arguments = func_get_args();
    $arrays     = $arguments[0];
    for ($c = (count($arguments)-1); $c > 0; $c--)
    {
        if (in_array($arguments[$c], array(SORT_ASC , SORT_DESC)))
        {
                continue;
        }
        $compare = create_function('$a,$b','return strcasecmp($a["'.$arguments[$c].'"], $b["'.$arguments[$c].'"]);');
        usort($arrays, $compare);
        if ($arguments[$c+1] == SORT_DESC)
        {
                $arrays = array_reverse($arrays);
        }
    }
    return $arrays ;
}

I call it like this:

$alliances = array_alternate_multisort($alliances, "output", SORT_DESC, "score", SORT_DESC);

How can I replace this with a function without calling create_function()?

Answer 1

You can use an anonymous function instead:

$compare = function ($a, $b) use ($arguments, $c) {
    return strcasecmp($a[$arguments[$c]], $b[$arguments[$c]]);
};

Untested but should be close enough

The use keyword allows you to inherit variables from the parent scope inside your function.