YaLinqo\Enumerable::where PHP Method

    public function where($predicate)
    {
        $predicate = Utils::createLambda($predicate, 'v,k');
        return new self(function () use($predicate) {
            foreach ($this as $k => $v) {
                if ($predicate($v, $k)) {
                    (yield $k => $v);
                }
            }
        });
    }