Asynchronous Control Flow Patterns

In the previous post, I covered how to avoid common pitfalls when using Promises. In this post, we’ll look at how Promises and JavaScript’s collection manipulation functions (read map and reduce) can be combined together to implement a few async control flow patterns. Continue reading

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JavaScript Promises – Gotchas and Anti Patterns

tl;dr

  • Flatten the Promise chain whenever possible
  • Straighten multiple nested promises with q.all() and q.spread()
  • Don’t break the Promise chain. Make sure that the last promise is returned to the caller.
  • Don’t overuse deferreds. Use them to promisify callback functions. In case a function returns a promise, it’s just better to form a chain with that same promise.

The long version

Continue reading

Validations with Ember.js

These days, with the rise of the single page applications, there has been a steady rise in the number of complete websites that are built on a client side JavaScript framework.
At any given point of time, these sites have always had the need for validations that they need to run client side.

Recently, while working on a pet-project using Ember.js as the client side framework and jQuery for running my client side validations, I came across a rather interesting question.
How would you handle client side validations with a framework such as Ember.js?  Continue reading

Code Jugalbandi

In Indian classical music, we have Jugalbandi, where two musicians or vocalists engage in playful competition.

A typical jugalbandi between a Flutist and a Percussionist plays out like this:

The percussionist listens to the intricate compositions played by the flutist and recreates them symmetrically. Needless to say, this often results in an exhilarating musical experience for the audience.

On a similar metaphor, I am proposing the idea of Code Jugalbandi across multiple programming languages (not just two) and see how the same code is rendered using different languages. Continue reading