docs: function listen () {
      keys.map(function (key) {
        var obs = observable[key]
        releases.push(obs(function (val) {
          if (!isSame(val, object[key], comparer)) {
            object[key] = val
            if (!suspendBroadcast) {
              binder.broadcast(object)
            }
          }
        }))
      })
    }