             bool attributeOldValue,
              bool characterDataOldValue,
              List&lt;String&gt; attributeFilter}) {

  // Parse options into map of known type.
  var parsedOptions = _createDict();

  // Override options passed in the map with named optional arguments.
  override(key, value) {
    if (value != null) _add(parsedOptions, key, value);
  }

  override(&apos;childList&apos;, childList);
  override(&apos;attributes&apos;, attributes);
  override(&apos;characterData&apos;, character