Gain insights into metaprogramming in Elixir. Delve into macros and discover how to elevate your coding skills, creating powerful libraries with concise, efficient code.

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Get introduced to the concept of metaprogramming. Learn how to level up your programming skills by discovering the full potential of the macro system in Elixir. Understand the ins and outs of metaprogramming at a fundamental level and write incredible libraries by doing more with less code.

Metaprogramming in Elixir

If we write a web service, we'll probably need to validate and convert _MIME_ types to their file extension. For example, when a request comes into the server with an **_Accept_** header of _`application/javascript`_, we must know how to handle this _MIME_ type and render a `.js` template. 



To tackle this problem in most languages, we would store the __MIME__ data in a map and consult the keyspace for __MIME-type__ conversions. This can become tedious with large datasets where we would need to convert the data by hand into a format representable within our programs. Fortunately, Elixir makes this easy for us with just a touch of metaprogramming. So let’s experiment with it a bit.

# Making use of existing datasets 

Instead of writing a bunch of code by hand, we’ll take a publicly available __MIME-type__ dataset and generate function heads to perform conversions. Our solution will require only ten lines of code while remaining fast and maintainable.

We will take a well-formatted __MIME-type__ dataset to serve as the basis of our implementation. Let’s discuss the first five lines of the file to understand how we can parse it into function definitions.

Learn how to use metaprogramming for MIME library goals of supporting text in character sets other than ASCII.

Introduction

The Language of Macros

Extending Elixir with Metaprogramming

Advanced Compile-Time Code Generation

Code Generation from Git API

How to Test Macros

Create an HTML Domain-Specific Language

With Great Power Comes Great Responsibility (and Fun!)

MIME-Type Conversion

Making use of existing datasets