Book Image

Learning Elixir

By : Kenny Ballou, Kenneth Ballou
Book Image

Learning Elixir

By: Kenny Ballou, Kenneth Ballou

Overview of this book

Elixir, based on Erlang’s virtual machine and ecosystem, makes it easier to achieve scalability, concurrency, fault tolerance, and high availability goals that are pursued by developers using any programming language or programming paradigm. Elixir is a modern programming language that utilizes the benefits offered by Erlang VM without really incorporating the complex syntaxes of Erlang. Learning to program using Elixir will teach many things that are very beneficial to programming as a craft, even if at the end of the day, the programmer isn't using Elixir. This book will teach you concepts and principles important to any complex, scalable, and resilient application. Mostly, applications are historically difficult to reason about, but using the concepts in this book, they will become easy and enjoyable. It will teach you the functional programing ropes, to enable them to create better and more scalable applications, and you will explore how Elixir can help you achieve new programming heights. You will also glean a firm understanding of basics of OTP and the available generic, provided functionality for creating resilient complex systems. Furthermore, you will learn the basics of metaprogramming: modifying and extending Elixir to suite your needs.
Table of Contents (16 chapters)
Learning Elixir
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Named functions


Named functions, unlike anonymous functions, require a module for definition. That is, to define a named function we must define the function inside a module.

Here, we combine what we learned about modules and anonymous functions a bit, and we define our square function again, though, this time, we define it inside a module named MyMath. Go ahead and create a file called mymath.exs and put the following code into it:

defmodule MyMath do

  def square(x) do
    x * x
  end

end

Here, we are simply defining a function, square, which takes a single element, and returns the result of x * x. This really looks not much different from our previous versions except for being defined inside a module.

How do we run this module and see whether it works? Well, you might have tried $ elixir mymath.exs but that probably didn't do anything interesting...

The answer lies in importing the module in an interactive session. First, make sure your working directory is the same as the directory you...