code: function attributable(form, c, name) {
    if (form._vals == null)
      form._vals = {};
    if (form._update == null)
      form._update = function () {
        for (var p in form._vals)
          form._vals[p].data == form._data[p];
      }
    form._vals[name] = c;
    c.on('change', function () {
      form._data[name] = c.data;
      form.emit('change');
    });
  }
docs: form field utility