QueryPath\CSS\QueryPathEventHandler::nthOfTypeChild PHP Метод

    protected function nthOfTypeChild($groupSize, $elementInGroup, $lastChild)
    {
        // EXPERIMENTAL: New in Quark. This should be substantially faster
        // than the old (jQuery-ish) version. It still has E_STRICT violations
        // though.
        $parents = new \SplObjectStorage();
        $matches = new \SplObjectStorage();
        $i = 0;
        foreach ($this->matches as $item) {
            $parent = $item->parentNode;
            // Build up an array of all of children of this parent, and store the
            // index of each element for reference later. We only need to do this
            // once per parent, though.
            if (!$parents->contains($parent)) {
                $c = 0;
                foreach ($parent->childNodes as $child) {
                    // This doesn't totally make sense, since the CSS 3 spec does not require that
                    // this pseudo-class be adjoined to an element (e.g. ' :nth-of-type' is allowed).
                    if ($child->nodeType == XML_ELEMENT_NODE && $child->tagName == $item->tagName) {
                        // This may break E_STRICT.
                        $child->nodeIndex = ++$c;
                    }
                }
                // This may break E_STRICT.
                $parent->numElements = $c;
                $parents->attach($parent);
            }
            // If we are looking for the last child, we count from the end of a list.
            // Note that we add 1 because CSS indices begin at 1, not 0.
            if ($lastChild) {
                $indexToMatch = $item->parentNode->numElements - $item->nodeIndex + 1;
            } else {
                $indexToMatch = $item->nodeIndex;
            }
            // If group size is 0, then we return element at the right index.
            if ($groupSize == 0) {
                if ($indexToMatch == $elementInGroup) {
                    $matches->attach($item);
                }
            } else {
                if (($indexToMatch - $elementInGroup) % $groupSize == 0 && ($indexToMatch - $elementInGroup) / $groupSize >= 0) {
                    $matches->attach($item);
                }
            }
            // Iterate.
            ++$i;
        }
        $this->matches = $matches;
    }