// define-attribute! :: String, Object, Element -> IO String
function define_attribute(key, subject, source) {
  var value = source.getAttribute(key) || subject[key]
  return subject[key] = value }

function make_menu(subject, source) {
  return this._buildMenuObj(source, createId) }

function make_item(subject, source) {
  var item = make_item(item)
  define_attribute('label',  subject, source)
  define_attribute('icon', subject, source)
  return item }

function build_menu(children) {
  var menuObj = { type:  'menu' }
  menuObj.items = children.map(to_menu_item.bind(this, menuObj))
  return menuObj }

function to_menu_item(subject, child) {
  return child.nodeName == 'MENU'?      make_menu.call(this, subject, child)
  :      child.nodeName == 'MENUITEM'?  make_item.call(this, subject, child)
  :      /* otherwise */                throw Error('Unknow type: ' + child.nodeName) }


/* -- Original code --
  var menuObj = {
      type: 'menu',
      items: []
    };
    if (menu.getAttribute('label')) {
      menuObj.label = menu.getAttribute('label');
    }

    for (var i = 0, child; child = menu.children[i++];) {
      if (child.nodeName === 'MENU') {
        menuObj.items.push(this._buildMenuObj(child, createId));
        break;
      }
      if (child.nodeName === 'MENUITEM') {
        var menuitem = {id: createId(child), type: 'menuitem'};
        if (child.getAttribute('label')) {
          menuitem.label = child.getAttribute('label');
        }
        if (child.getAttribute('icon')) {
          menuitem.icon = child.getAttribute('icon');
        }
        menuObj.items.push(menuitem);
      }
    }

    return menuObj;
*/