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

Take the `translator` module for reference.
```
defmodule I18n do
  use Translator

  locale "en",
    flash: [
      hello: "Hello %{first} %{last}!",
      bye: "Bye, %{name}!"
    ],
    users: [
      title: "Users",
    ]

  locale "fr",
    flash: [
      hello: "Salut %{first} %{last}!",
      bye: "Au revoir, %{name}!"
    ],
    users: [
      title: "Utilisateurs",
    ]

  locale "ur",
    flash: [
      
      hello: "Salam %{first} %{last}!",
      bye: "Khuda Hafiz, %{name}!"
    ],
    users: [
      title: "Utilisateurs",
    ]
end
```
What would be the output of the following command?
```
iex> I18n.t("ur", "flash.hello", first: "Harry", last: "Potter")
```



Take the <code>translator</code> module for reference.
<pre><code>defmodule I18n do
 use Translator

 locale &quot;en&quot;,
 flash: [
 hello: &quot;Hello %{first} %{last}!&quot;,
 bye: &quot;Bye, %{name}!&quot;
 ],
 users: [
 title: &quot;Users&quot;,
 ]

 locale &quot;fr&quot;,
 flash: [
 hello: &quot;Salut %{first} %{last}!&quot;,
 bye: &quot;Au revoir, %{name}!&quot;
 ],
 users: [
 title: &quot;Utilisateurs&quot;,
 ]

 locale &quot;ur&quot;,
 flash: [
 
 hello: &quot;Salam %{first} %{last}!&quot;,
 bye: &quot;Khuda Hafiz, %{name}!&quot;
 ],
 users: [
 title: &quot;Utilisateurs&quot;,
 ]
end
</code></pre>
What would be the output of the following command?
<pre><code>iex&gt; I18n.t(&quot;ur&quot;, &quot;flash.hello&quot;, first: &quot;Harry&quot;, last: &quot;Potter&quot;)
</code></pre>

```
I18n.t("en", "flash.bye", first: "Harry", last: "Potter")

```
I18n.t("fr", "flash.bye", first: "Harry", last: "Wizard")

```
I18n.t("fr", "flash.bye", name: "Harry Wizard")

Take the `translator` module for reference.
```
defmodule I18n do
  use Translator

  locale "en",
    flash: [
      hello: "Hello %{first} %{last}!",
      bye: "Bye, %{name}!"
    ],
    users: [
      title: "Users",
    ]

  locale "fr",
    flash: [
      hello: "Salut %{first} %{last}!",
      bye: "Au revoir, %{name}!"
    ],
    users: [
      title: "Utilisateurs",
    ]

  locale "ur",
    flash: [
      
      hello: "Salam %{first} %{last}!",
      bye: "Khuda Hafiz, %{name}!"
    ],
    users: [
      title: "Utilisateurs",
    ]
end
```
Which function should we run to get the following output?
```
"Au revoir Harry Wizard!"
```



Take the <code>translator</code> module for reference.
<pre><code>defmodule I18n do
 use Translator

 locale &quot;en&quot;,
 flash: [
 hello: &quot;Hello %{first} %{last}!&quot;,
 bye: &quot;Bye, %{name}!&quot;
 ],
 users: [
 title: &quot;Users&quot;,
 ]

 locale &quot;fr&quot;,
 flash: [
 hello: &quot;Salut %{first} %{last}!&quot;,
 bye: &quot;Au revoir, %{name}!&quot;
 ],
 users: [
 title: &quot;Utilisateurs&quot;,
 ]

 locale &quot;ur&quot;,
 flash: [
 
 hello: &quot;Salam %{first} %{last}!&quot;,
 bye: &quot;Khuda Hafiz, %{name}!&quot;
 ],
 users: [
 title: &quot;Utilisateurs&quot;,
 ]
end
</code></pre>
Which function should we run to get the following output?
<pre><code>&quot;Au revoir Harry Wizard!&quot;
</code></pre>

```
I18n.t("wizard", "flash.result", first: "Harry", last: "Wizard")

```
I18n.t("wizard", "flash.result", first: "Harry", last: "Potter")

```
I18n.t("muggle", "flash.result", first: "Harry", last: "Potter")

Take the `translator` module for reference.
```
defmodule I18n do
  use Translator

  locale "wizard",
    flash: [
      result: "%{first} %{last} is a wizard!"
    ],
    users: [
      title: "Users",
    ]

  locale "muggle",
    flash: [
      result: "%{first} %{last} is not a wizard!"
    ],
    users: [
      title: "Utilisateurs",
    ]
end
```
Which function should we run to get the following output?
```
"Harry Potter is not a wizard!"
```

Take the <code>translator</code> module for reference.
<pre><code>defmodule I18n do
 use Translator

 locale &quot;wizard&quot;,
 flash: [
 result: &quot;%{first} %{last} is a wizard!&quot;
 ],
 users: [
 title: &quot;Users&quot;,
 ]

 locale &quot;muggle&quot;,
 flash: [
 result: &quot;%{first} %{last} is not a wizard!&quot;
 ],
 users: [
 title: &quot;Utilisateurs&quot;,
 ]
end
</code></pre>
Which function should we run to get the following output?
<pre><code>&quot;Harry Potter is not a wizard!&quot;
</code></pre>

```
I18n.t("muggle", "flash.result", name: "Harry")

```
I18n.t("wizard", "flash.result", name: "Harry")

Take the `translator` module for reference.
```
defmodule I18n do
  use Translator

  locale "wizard",
    flash: [
      result: "%{name} is a wizard!"
    ],
    users: [
      title: "Users",
    ]

  locale "muggle",
    flash: [
      result: "%{first} %{last} is not a wizard!"
    ],
    users: [
      title: "Utilisateurs",
    ]
end
```
Which function should we run to get the following output?
```
"Harry is a wizard!"
```

Take the <code>translator</code> module for reference.
<pre><code>defmodule I18n do
 use Translator

 locale &quot;wizard&quot;,
 flash: [
 result: &quot;%{name} is a wizard!&quot;
 ],
 users: [
 title: &quot;Users&quot;,
 ]

 locale &quot;muggle&quot;,
 flash: [
 result: &quot;%{first} %{last} is not a wizard!&quot;
 ],
 users: [
 title: &quot;Utilisateurs&quot;,
 ]
end
</code></pre>
Which function should we run to get the following output?
<pre><code>&quot;Harry is a wizard!&quot;
</code></pre>

```
I18n.t("muggle2", "flash.result", name: "Harry")

```
I18n.t("muggle1", "flash.result", first: "Harry", last: "Potter")

```
I18n.t("muggle2", "flash.result", first: "Harry", last: "Potter")

Take the `translator` module for reference.
```
defmodule I18n do
  use Translator

  locale "muggle1",
    flash: [
      result: "%{first} %{last} is not a wizard!"
    ],
    users: [
      title: "Users",
    ]

  locale "muggle2",
    flash: [
      result: "%name is not a wizard!"
    ],
    users: [
      title: "Utilisateurs",
    ]
end
```
Which function should we run to get the following output?
```
"Harry Potter is not a wizard!"
```

Take the <code>translator</code> module for reference.
<pre><code>defmodule I18n do
 use Translator

 locale &quot;muggle1&quot;,
 flash: [
 result: &quot;%{first} %{last} is not a wizard!&quot;
 ],
 users: [
 title: &quot;Users&quot;,
 ]

 locale &quot;muggle2&quot;,
 flash: [
 result: &quot;%name is not a wizard!&quot;
 ],
 users: [
 title: &quot;Utilisateurs&quot;,
 ]
end
</code></pre>
Which function should we run to get the following output?
<pre><code>&quot;Harry Potter is not a wizard!&quot;
</code></pre>

In Elixir, which module attribute is used to specify compile-time resources that the module in use depends on?

In Elixir, which module attribute is used to specify compile-time resources that the module in use depends on?

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!)

Test Your Knowledge!