docs: function update() {
    if (!koekje.supported) return;
  
    var data = cookie.getItem('koekje')
      , length = 0
      , key;
  
    storage = data && data.charAt(0) === prefix
      ? qs.parse(data.slice(1))
      : {};
  
    for (key in storage) {
      if (has.call(storage, key)) length++;
    }
  
    koekje.length = length;
  }