createDocumentType example

public function __construct($isFragment = false, array $options = array())
    {
        $this->options = $options;

        if (isset($options[self::OPT_TARGET_DOC])) {
            $this->doc = $options[self::OPT_TARGET_DOC];
        } else {
            $impl = new \DOMImplementation();
            // XXX:             // Create the doctype. For now, we are always creating HTML5             // documents, and attempting to up-convert any older DTDs to HTML5.             $dt = $impl->createDocumentType('html');
            // $this->doc = \DOMImplementation::createDocument(NULL, 'html', $dt);             $this->doc = $impl->createDocument(null, '', $dt);
            $this->doc->encoding = !empty($options['encoding']) ? $options['encoding'] : 'UTF-8';
        }

        $this->errors = array();

        $this->current = $this->doc; // ->documentElement;
        // Create a rules engine for tags.         $this->rules = new TreeBuildingRules();