[no-espam]

I was bummed `await` and `defer` was not merged in. However, after thinking about it, the same result can be had using a good async library. The code is self-documenting if you choose good property names.

.

follow = (from, to, cb) ->

  # Invokes four async operations in a series, which requires 4 `await`, `defer` 
  # using iced. Note how error handling is handled 
  # in one place rather than each step.
  # That's a big drawback for me with await/defer.

  async.series
    user: (cb) -> User.find name:from, cb

    addFollowing: (cb, results) ->
      results.user.following.push to
      User.save results.user, cb

    followee: (cb) ->
      User.find name:to, cb

    addFollower: (cb, results) ->
      results.followee.followers.push from
      User.update results.followee, cb
    
  , (err, results)
    cb err, results