Async programming in JS/Coffee

Imagine we have a client library that talks to a server asynchronously

• client.login(u, p, ..) : LogIn with username and password
• client.getPosts(userId, ..) : Get array of posts of a user
• client.countPostLike(post, ..) : Like one post
• client.logout(..) : Log out current user

Now imagine you want to like all the posts of a user one by one (serialized) and logout, using plain old-style js and node-style callbacks.

You can implement this in many ways. Let me discuss some

1. Node-style callbacks
2. Promises (Q.js)
3. ES6 Generators/yield
4. Generators and promises (Q.js) together

Further readings

If you are interested into generators and async stuff without promises I suggest you go on reading this article. I personally prefer promises.