Error handling flow in Elixir

cover Juggling messages with a smile on your face
I've been playing around with Phoenix in the last couple weeks and it's been great fun!:) Amidst my dwellings, I wanted to implement an API call to create a username and send a verification e-mail in one step.

This means that both must be successful in order to procceed. Let's forget how to revert the user creation in case the e-mail fails for now. Now, how would we do that?

In Ruby we could do something like:

It's pretty succint right? But that if, unless and return in the middle of the method... Oh boy, it pisses me off. The get_error also kinda itches me.

Elixir's pattern matching allows us to make the code a bit more elegant. We can expose information throughout the code in a more ordered and straight forward fashion:

Pretty cool, heh? Code's more readable, no flow breaks and no ifs laying around. The only requirement is to follow the {:ok, whatever} and {:error, error_struct} format.

That said, Elixir 1.2 brought us with! Here's an updated take on this kind of issue!

Check my other Elixir posts here