Get Started With Elixir

What is Elixir?

Elixir is a dynamically typed, compiled, functional programming language built on top of the Erlang virtual machine best used for applications that are highly concurrent. Erlang was created in 1986 by Ericcson to create more reliable phone switching. Elixir was created on top of the Erlang Virtual Machine called BEAM, which allows Elixir to have the same functionality as Erlang while having a different syntax and features. Elixir uses a very Ruby like syntax that you'll see in the examples below. To learn more about the difference between functional and object oriented programming I have resources linked at the bottom of the article.

Installing Elixir

To install Elixir, head over to this link and follow the instructions depending on your operating system. Since I'm on Mac and use Homebrew all I had to do was type brew install elixir into the terminal to install everything I needed. If you use VSCode you can also install this extension to help with things like auto completion and syntax highlighting.

Using IEX

Elixir comes with its own terminal based REPL called IEX that can be used to test functions. If you are familiar with Ruby this is just like IRB or if you have a JavaScript background it would be similar to using Node in the terminal. To use IEX type IEX in your terminal. After starting your REPL to make sure it's working try typing IO.puts "Hello, world!" in the terminal, this should output two things, first you'll see the string Hello, world! printed then you'll see :ok returned.

Using Elixir

As I said earlier, Elixir uses a Ruby like syntax. If you have spent any amount of time building projects with Ruby, learning and reading Elixir will probably come pretty quickly. As an easy walk through I'll show you how we can create a program that solves FizzBuzz, the code for this demo came from here. I wish I could say I learned Elixir in 3 days but I've only just scraped the surface, check out that link if you're interested in another possible way to solve fizzbuzz and I'll also have a link with more solutions at the bottom of the article. This link has a working version of what we're after if you're not familiar with FizzBuzz.

First, create a new directory for this file. To do this you can type mkdir elixir-fizzbuzz in your terminal. Next, you'll need to change directories into your new directory by running the following command cd elixir-fizbuzz.

Now that you're in your new directory you can create a new Elixir file. There are a couple different file extensions you can use to create an Elixir file, each with a slightly different use case. This stack overflow question has a good answer for when to use which type of file extension. For this example we'll create a file called 'fizzbuzz.exs', to do this you'll need to run the command touch fizzbuzz.exs.

After creating the file open the directory in your text editor of choice.

First we'll create a module

#Define module
defmodule Solution do
end

Next we'll start writing our functions

#Define module
defmodule Solution do
    #Define type specs
    @spec fizz_buzz(n :: integer) :: [String.t]
    #Define FizzBuzz function
    def fizz_buzz(n) do
        #Loop through range of numbers
        for i <- 1..n do
            
        end
    end

end

Now we can call a private function that checks whether or not each number is divisible by 3 and/or 5.

#Define module
defmodule Solution do
    #Define type specs
    @spec fizz_buzz(n :: integer) :: [String.t]
    #Define FizzBuzz function
    def fizz_buzz(n) do
        #Loop through range of numbers
        for i <- 1..n do
            #Call Result() for each number in the range
            result(i)
            end
        end
    end
    #Handle divisble by 3 & 5
    defp result(n) when rem(n, 15) == 0, do: IO.puts("FizzBuzz")
    #Handle divisble by 3
    defp result(n) when rem(n, 3) == 0, do: IO.puts("Fizz")
    #Handle divisble by 5
    defp result(n) when rem(n, 5) == 0, do: IO.puts("Buzz")
    #Handle not divisble by 3 or 5
    defp result(n), do: IO.puts(Integer.to_string(n))
    
end

#Call function fizz_buzz/1 with range of 100 from Solution module
Solution.fizz_buzz(100)

Now that our functions are all defined lets run our code, to do that in your terminal type the command elixir fizzbuzz.exs.

Uses for Elixir

If you check the Stack Overflow developer survey you'll see there aren't really a lot of developers actually using Elixir professionally, with just 1.74% of respondants saying it's a language they use. It is however top 5 in the loved vs dreaded category, meaning most people that use it love it. Elixir is often used on projects that need to support a very large user base all at once, as well as projects that require fast responses. As of right now on there are 12 companies on the Elixir lang website that are currently using Elixir as a solution to a variety of problems. For example, Discord uses Elixir as the foundation of its messaging service which supports 100 million monthly active users. Change.org uses Elixir as they found it faster than the comptetion. There hasn't been a lot of uptake in Elixir or functional programming as a whole, so it may not be the most useful skill to learn if you want to get job ready for as many jobs as possible. If instead you are trying to figure out how you can create an app that is highly scalable and performant, Elixir may be a good option for you.

Resources

Here are a few resources that may come in handy as you learn more about Elixir:

• Awesome video from Fireship.io
• 7 ways to solve fizzbuzz with Elixir
• Install Elixir
• How I'm learning Elixir
• My other posts