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

# Supporting more tag attributes
To make the HTML library truly useful to the world, let’s add support for tag attributes such as `class` and `id`. Let’s extend the DSL to support an optional keyword list that gets translated into tag attributes for each macro.





For example, our goal is to support the following API:

div id: "main" do
  h1 class: "title", do: text("Welcome!") 
  div class: "row" do
    div class: "column" do 
      p "Hello!"
    end 
  end
  button onclick: "javascript: history.go(-1);" do 
    text "Back"
  end 
end

## Replacing the `tag` macro
Let’s revisit our `Html` module from the last lesson and add support for tag attributes. Now, replace the `tag/2` macro on **line 4**, as given in the project in the previous lesson: [Supporting the Entire HTML Spec with Macros](https://www.educative.io/courses/metaprogramming-elixir/supporting-the-entire-html-spec-with-macros). Update the `for tag <- @tags` comprehension on **line 8** with the following code and save the updated listing as `html_step3.exs`.

Let’s extend our DSL to support an optional keyword list that is translated into tag attributes for each macro.

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!)

Enhancing API with HTML Attribute Support

Supporting more tag attributes

Replacing the `tag` macro