function $(id) {
	return document.getElementById(id);
}

function containsDOM (container, containee) {
  var isParent = false;
  do {
    if ((isParent = container == containee))
      break;
    containee = containee.parentNode;
  }
  while (containee != null);
  return isParent;
}

function checkMouseEnter (element, evt) {
  if (element.contains && evt.fromElement) {
    return !element.contains(evt.fromElement);
  }
  else if (evt.relatedTarget) {
    return !containsDOM(element, evt.relatedTarget);
  }
}

function checkMouseLeave (element, evt) {
  if (element.contains && evt.toElement) {
    return !element.contains(evt.toElement);
  }
  else if (evt.relatedTarget) {
    return !containsDOM(element, evt.relatedTarget);
  }
}