Allow "static" type

Hi all, I would like to know your opinion about using "static" as type-hint similar to "self" and how simple / complex it would be to implement. Example - using static: https://3v4l.org/XqDma class Base {

    public static function test(static $obj) : static {
        echo get_class($obj) . "\n";
        return new static($obj);
    }

} class Ext extends Base {} $base = new Base; $ext = new Ext; Base::test($base); Base::test($ext); Ext::test($ext); Ext::test($base); Example - using self: https://3v4l.org/Tp7k6 - Boilerplate code to check if the given argument is an instance of static - No way for IDEs to test Ext::test returning an instance of Ext class Base {

    public static function test(self $obj) : self {
        echo get_class($obj) . "\n";

        if (!$obj instanceof static) {
            throw new InvalidArgumentException(sprintf(
                "Object (%s) must be an instance of %s",
                get_class($obj),
                static::class
            ));
        }

        return new static($obj);
    }

} class Ext extends Base {} $base = new Base; $ext = new Ext; Base::test($base); Base::test($ext); Ext::test($ext); Ext::test($base); Thanks Marc