uksort()

uksort(...$args): bool

Parameters

Name	Type	Description
$a	array	map to sort (in place)
$cmp	closure	comparator receiving two keys

true; sorts by key using the closure.

$m = ["b" => 2, "a" => 1];
uksort($m, fn($x, $y) => $x <=> $y);
echo array_key_first($m);