Aaron
Lasseigne

Most of the code I write is written in Ruby. I work with it during the day and I play with it at night. I’m a full stack web developer so I get to cavort with JavaScript and CoffeeScript regularly. But every now and then I like to pick a language and take it for a spin. I haven’t done it as often as I would like but when I do it’s always interesting. Recently, I decided to take some time and toy around with José Valim’s new language Elixir¹. I’ll skip to the end and tell you this: I’m having a lot of fun.

Does it run?

If you’re going to play with a language you’ll need to have access to it. You can try Elixir out in the browser but that’ll only get you so far. I want to work with it locally. Thankfully, installing it was a breeze. It has a variety of installers for Windows, Linux, and OSX so it should be simple on any system. No complicated command line crap here.

How about a development environment?

I’m a Vim guy so my first thought was to see if there was a good plugin. It turns out that the Elixir crew has released a plugin for Vim, Emacs, and TextMate (which covers Sublime). It really feels like they want people to be comfortable getting up and running.

A brief word from Dave Thomas.

If you’re in the Ruby community you know who Dave Thomas is. Primarily because he wrote the book on Ruby. Literally. He’s currently writing a book on Elixir and he’s done a free video introducing the language.

About a week ago I was fortunate enough to hear him speak on the topic and I can tell you he’s passionate about Elixir and about functional programming. It encouraged me to go home and spend some more time exploring.

Roman Numerals

Inspired by a kata Greg Vaughn showed after Dave’s talk, I prompty started coding a basic Roman numeral converter. After writing up some tests I let the typing begin. When it came to pattern matching I was a bit dubious. Normally I avoid conditions if I can so I was worried it would feel like I was overusing them. After working through the Roman numerals I didn’t have that feeling. It felt clean and tidy. It was easy to read and reason about.

defmodule RomanNumeral do
  def convert(n) when n >= 10, do: remove_and_continue(n, "X", 10)
  def convert(9),              do: "IX"
  def convert(n) when n >= 5,  do: remove_and_continue(n, "V", 5)
  def convert(4),              do: "IV"
  def convert(n),              do: String.duplicate("I", n)

  defp remove_and_continue(total, roman, number) do
    String.duplicate(roman, div(total, number)) <> convert(rem(total, number))
  end
end

The full code with tests can be found here.

Project Time

I wanted to try taking on a project. Using the getting started guide on elixir-lang.org I decided to make something like a poor man’s Memcached. Learning about OTP, processes, supervisors, and general language whatnot proved a bit challenging. Eventually I got my head around enough of it to finish and I’m satisfied with the final product. You can check out the code at AaronLasseigne/ex_cache.

I haven’t drank the Kool-Aid yet.

I feel very comfortable with Elixir. I’ve been looking for a functional language to really sink my teeth into and I might have found it. Having said that, Elixir does have some warts. Guard clauses are a bit too limited especially when it comes to strings (no regular expression comparisons). Additionally, data types are comparable (e.g. 1 < :atom # true) which strikes me as bizarre and makes me worry about false positive comparisons in guard clauses.

Elixir is all of the power of Erlang with a Ruby inspired syntax. It’s got a chance to be something and even if it doesn’t work out it’ll provide a nice stepping stone into the world of functional programming and immutable data. Personally I hope it has a lot of success because right now I’m having a lot of fun.