Skip to content

Minimalistic HTML templates for Elixir, inspired by Slim.

License

Notifications You must be signed in to change notification settings

tensiondriven/slime

 
 

Repository files navigation

Slime Continuous Integration Hex Version License

A refreshing way to slim down your markup in Elixir.

Slime is an Elixir library for rendering Slim-like templates as HTML.

For use with Phoenix, please see PhoenixSlime.

Easily turn this:

doctype html
html
  head
    meta name="keywords" description="Slime"
    title = site_title
    javascript:
      alert('Slime supports embedded javascript!');
  body
    #id.class
      ul
        = Enum.map [1, 2], fn x ->
          li = x

Into this:

<!DOCTYPE html>
<html>
<head>
  <meta name="keywords" description="Slime">
  <title>Website Title</title>
  <script>alert('Slime supports embedded javascript!');</script>
</head>

<body>
  <div class="class" id="id">
    <ul>
      <li>1</li>
      <li>2</li>
    </ul>
  </div>
</body>
</html>

With this:

Slime.render(source, site_title: "Website Title")

Reference

Tags

Starting a line with a string followed by a space will create an html tag, as follows:

tt
  Always bring a towel.
<tt>Always bring a towel.<tt>

Attributes

Attributes can be assigned in a similar fashion to regular HTML.

a href="elixir-lang.org" target="_blank" Elixir
<a href="elixir-lang.org" target="_blank">Elixir</a>

Elixir expressions can be used as attribute values using the interpolation syntax.

a href="#{my_variable}" Elixir
<a href="elixir-lang.org">Elixir</a>

Boolean attributes can be set using boolean values

input type="checkbox" checked=true
input type="checkbox" checked=false
<input type="checkbox" checked>
<input type="checkbox">

There is a literal syntax for class and id attributes

.foo.bar
select.bar
#foo
body#bar
<div class="foo bar"></div>
<select class="bar"></select>
<div id"foo"></div>
<body id="bar"></body>

See HEEx Support for assigning attributes when rendering to HEEx.

Code

Elixir can be written inline using - and =.

- evalutes the expression. = evalutes the expression, and then inserts the value into template.

- number = 40
p = number + 2
<p>42</p>

The interpolation syntax can be used to insert expressions into text.

- name = "Felix"
p My cat's name is #{name}
<p>My cat's name is Felix</p>

Comments

Lines can be commented out using the / character.

/ p This line is commented out
p This line is not
<p>This line is not</p>

HTML <!-- --> comments can be inserted using /!

/! Hello, world!
<!-- Hello, world! -->

Conditionals

We can use the regular Elixir flow control such as the if expression.

- condition = true
= if condition do
  p It was true.
- else
  p It was false.
<p>It was true.</p>

Doctype

There are shortcuts for common doctypes.

doctype html
doctype xml
doctype transitional
doctype strict
doctype frameset
doctype 1.1
doctype basic
doctype mobile
<!DOCTYPE html>
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.1//EN" "http://www.w3.org/TR/xhtml-basic/xhtml-basic11.dtd">
<!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.2//EN" "http://www.openmobilealliance.org/tech/DTD/xhtml-mobile12.dtd">

Iteration

Elixir's collection manipulation expressions can be used to iterate over collections in your templates.

- names = ["Sarah", "Mia", "Harry"]

/! Enum.map
= Enum.map names, fn name ->
  p = name

/! for comprehension
= for name <- names do
  h1 = name
<!-- Enum.map -->
<p>Sarah</p>
<p>Mia</p>
<p>Harry</p>

<!-- for comprehension -->
<h1>Sarah</h1>
<h1>Mia</h1>
<h1>Harry</h1>

Embedded engines

Examples:

javascript:
  console.log("Test javascript");

css:
  body {
    color: black;
  }

elixir:
  a = [1, 2, 3]
  b = Enum.map(a, &(&1 + 1))

eex:
  Hello from <%= "eex" %>

You can define your own embedded engine in slime application config:

# config.exs
config :slime, :embedded_engines, %{
  markdown: MyApp.MarkdownEngine
}

# markdown_engine.ex
defmodule MyApp.MarkdownEngine do
  @behaviour Slime.Parser.EmbeddedEngine

  def render(text, _options) do
    Earmark.to_html(text)
  end
end

Because the engines are being read on compile time you need to recompile the library after you have added new engines. You can do this by:

mix deps.compile slime --force

HEEx Support

To output HEEx instead of HTML, see phoenix_slime. This will cause slime to emit "html aware" HEEx with two differences from conventional HTML:

  • Attribute values will be wrapped in curley-braces ({}) instead of escaped EEx (#{}):

  • HTML Components will be prefixed with a dot. To render an HTML Component, prefix the component name with a colon (:). This will tell slime to render these html tags with a dot-prefix (.).

For example,

:greet user=@current_user.name
  | Hello there!

would create the following output:

<.greet user={@current_user.name}>Hello there!</.greet>

When using slime with Phoenix, the phoenix_slime package will call precompile_heex/2 and pass the resulting valid HEEx to EEx with Phoenix.LiveView.HTMLEngine as the engine: option. This will produce the final html.

Precompilation

Templates can be compiled into module functions like EEx templates, using functions Slime.function_from_file/5 and Slime.function_from_string/5.

To use slime templates (and Slime) with Phoenix, please see PhoenixSlime.

Differences to Ruby Slim

We aim for feature parity with the original Slim implementation, but we deviate in some respects. We do this to be true to Elixir – just like the original Slim implementation is true to its Ruby foundations.

For example, in Slime you do

= if condition do
  p It was true.
- else
  p It was false.

where Ruby Slim would do

- if condition
  p It was true.
- else
  p It was false.

Note the do and the initial =, because we render the return value of the conditional as a whole.

Slime also adds support for HEEx. See the section on HEEx Support.

Debugging

If you have trouble locating exceptions in Slime templates, you can add

config :slime, :keep_lines, true

to your config.exs file. With this option Slime will keep original template lines in result eex and html. Keep in mind, that output is slightly different from default Slime output, for example | works like ', and empty lines are not ignored.

Contributing

Feedback, feature requests, and fixes are welcomed and encouraged. Please make appropriate use of Issues and Pull Requests. All code should have accompanying tests.

License

MIT license. Please see LICENSE for details.

About

Minimalistic HTML templates for Elixir, inspired by Slim.

Resources

License

Stars

Watchers

Forks

Packages

No packages published

Languages

  • Elixir 96.3%
  • HTML 3.4%
  • Erlang 0.3%