Ruby2sass is a powerful and flexible Ruby DSL for generating SASS and CSS. It allows you to write your stylesheets using Ruby syntax, providing a more programmatic and dynamic approach to stylesheet generation. π
Add this line to your application's Gemfile:
gem 'ruby2sass'
And then execute:
$ bundle install
Or install it yourself as:
$ gem install ruby2sass
Here's a comprehensive example showcasing various features of Ruby2sass, along with the generated SASS output for each block:
require 'ruby2sass'
renderer = Ruby2sass::Renderer.new do
# Variables
primary_color = v('primary-color', '#007bff')
secondary_color = v('secondary-color', '#6c757d')
grid_columns = v('grid-columns', 12)
s('body') do
background_color primary_color
end
end
puts renderer.to_sass
Output:
$primary-color: #007bff;
$secondary-color: #6c757d;
$grid-columns: 12;
body {
background-color: #007bff;
}
renderer = Ruby2sass::Renderer.new do
# Mixins
mixin 'button-styles', '$bg-color' do
background_color '$bg-color'
padding '10px 15px'
border_radius '5px'
transition 'background-color 0.3s ease'
end
# Functions
function 'darken', '$color, $amount' do
raw '@return darken($color, $amount);'
end
end
puts renderer.to_sass
Output:
@mixin button-styles($bg-color) {
background-color: $bg-color;
padding: 10px 15px;
border-radius: 5px;
transition: background-color 0.3s ease;
}
@function darken($color, $amount) {
@return darken($color, $amount);
}
renderer = Ruby2sass::Renderer.new do
# Base styles
s('body') do
font_family "'Arial', sans-serif"
line_height '1.6'
color '#333'
end
# Container
s('.container') do
max_width '1200px'
margin '0 auto'
padding '0 15px'
end
end
puts renderer.to_sass
Output:
body {
font-family: 'Arial', sans-serif;
line-height: 1.6;
color: #333;
}
.container {
max-width: 1200px;
margin: 0 auto;
padding: 0 15px;
}
renderer = Ruby2sass::Renderer.new do
primary_color = v('primary-color', '#007bff')
secondary_color = v('secondary-color', '#6c757d')
# Buttons
s('.button') do |btn|
include 'button-styles', primary_color
btn.hover do
background_color "darken(#{primary_color}, 10%)"
end
end
s('.button-secondary') do |btn|
include 'button-styles', secondary_color
btn.hover do
background_color "darken(#{secondary_color}, 10%)"
end
end
end
puts renderer.to_sass
Output:
$primary-color: #007bff;
$secondary-color: #6c757d;
.button {
@include button-styles(#007bff);
&:hover {
background-color: darken(#007bff, 10%);
}
}
.button-secondary {
@include button-styles(#6c757d);
&:hover {
background-color: darken(#6c757d, 10%);
}
}
renderer = Ruby2sass::Renderer.new do
grid_columns = v('grid-columns', 12)
# Grid system using for loop
for_loop 'i', from: 1, to: grid_columns do
s(".col-\#{$i}") do
width "calc(100% / #{grid_columns} * \#{$i})"
float 'left'
padding '0 15px'
end
end
end
puts renderer.to_sass
Output:
$grid-columns: 12;
@for $i from 1 through 12 {
.col-#{$i} {
width: calc(100% / 12 * #{$i});
float: left;
padding: 0 15px;
}
}
renderer = Ruby2sass::Renderer.new do
# Color palette using each loop
colors = v('colors', '("primary": #007bff, "secondary": #6c757d, "success": #28a745, "danger": #dc3545)')
each_loop 'name, color', colors do
s(".\#{$name}-bg") do
background_color '$color'
end
s(".\#{$name}-text") do
color '$color'
end
end
end
puts renderer.to_sass
Output:
$colors: ("primary": #007bff, "secondary": #6c757d, "success": #28a745, "danger": #dc3545);
@each $name, $color in $colors {
.#{$name}-bg {
background-color: $color;
}
.#{$name}-text {
color: $color;
}
}
renderer = Ruby2sass::Renderer.new do
# Responsive font sizes using while loop
base_font = v('base-font-size', 16)
i = v('i', 6)
while_loop "#{i} > 0" do
s("h\#{$i}") do
font_size "#{base_font} + \#{$i}px"
end
raw "#{i} = #{i} - 1;"
end
end
puts renderer.to_sass
Output:
$base-font-size: 16;
$i: 6;
@while $i > 0 {
h#{$i} {
font-size: 16 + #{$i}px;
}
$i: $i - 1;
}
renderer = Ruby2sass::Renderer.new do
# Media queries
breakpoints = v('breakpoints', '("sm": 576px, "md": 768px, "lg": 992px, "xl": 1200px)')
each_loop 'name, width', breakpoints do
media "screen and (min-width: \#{$width})" do
s('.container') do
max_width '$width'
end
end
end
end
puts renderer.to_sass
Output:
$breakpoints: ("sm": 576px, "md": 768px, "lg": 992px, "xl": 1200px);
@each $name, $width in $breakpoints {
@media screen and (min-width: #{$width}) {
.container {
max-width: $width;
}
}
}
renderer = Ruby2sass::Renderer.new do
# Theme switching with if-else
theme = v('theme', 'light')
if_statement "#{theme} == 'light'" do
s('body') do
background_color '#fff'
color '#333'
end
end
else_statement do
s('body') do
background_color '#333'
color '#fff'
end
end
end
puts renderer.to_sass
Output:
$theme: light;
@if $theme == 'light' {
body {
background-color: #fff;
color: #333;
}
}
@else {
body {
background-color: #333;
color: #fff;
}
}
renderer = Ruby2sass::Renderer.new do
# Using raw SASS for complex selectors
raw <<~SCSS
nav {
ul {
margin: 0;
padding: 0;
list-style: none;
li { display: inline-block; }
a {
display: block;
padding: 6px 12px;
text-decoration: none;
}
}
}
SCSS
end
puts renderer.to_sass
Output:
nav {
ul {
margin: 0;
padding: 0;
list-style: none;
li { display: inline-block; }
a {
display: block;
padding: 6px 12px;
text-decoration: none;
}
}
}
This example demonstrates:
- Variable declaration using
v()
and usage - Mixins and includes
- Custom functions
- Nested selectors with yield
- Various types of loops (for, each, while) for generating classes and styles
- Media queries with dynamic breakpoints
- Conditional statements for theming
- Raw SASS input for complex nesting
The to_sass
method generates SASS output from your Ruby2sass DSL:
sass_output = renderer.to_sass
The to_css
method compiles your Ruby2sass DSL directly to CSS:
css_output = renderer.to_css(include: nil, compress: false)
Parameters:
include
: An array of file paths, strings, or IO objects to be included before the main SASS content.compress
: A boolean indicating whether the output CSS should be compressed (default is false).
Example with options:
css_output = renderer.to_css(
include: ['path/to/variables.sass', '$primary-color: #007bff;'],
compress: true
)
Ruby2sass supports:
- Variables with
v()
method - Mixins and includes
- Custom functions
- Nested selectors with yield for pseudo-classes and pseudo-elements
- Loops (for, each, while) with various use cases
- Conditionals (if-else)
- Media queries with dynamic breakpoints
- Keyframe animations
- Raw SASS input for complex scenarios
- CSS property method missing for easy property setting
Ruby2sass is designed to handle various sizes of SASS structures efficiently. Here are some benchmark results:
Structure Details:
Small (Depth: 3, Breadth: 3):
Total Selectors: 39
Total Properties: 117
SASS Size: 3.74 KB
CSS Size: 3.96 KB
Medium (Depth: 4, Breadth: 4):
Total Selectors: 340
Total Properties: 1020
SASS Size: 36.13 KB
CSS Size: 39.14 KB
Large (Depth: 5, Breadth: 5):
Total Selectors: 3905
Total Properties: 11715
SASS Size: 455.77 KB
CSS Size: 502.50 KB
Benchmark Results:
Ruby2sass small: 145.5 i/s
Ruby2sass medium: 20.0 i/s - 7.29x slower
Ruby2sass large: 1.7 i/s - 84.77x slower
These results show that Ruby2sass can handle small to medium-sized stylesheets very efficiently, while still being capable of processing larger stylesheets. π
After checking out the repo, run bin/setup
to install dependencies. Then, run rake spec
to run the tests. You can also run bin/console
for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install
.
Bug reports and pull requests are welcome on GitHub at https://github.com/sebyx07/ruby2sass.
The gem is available as open source under the terms of the MIT License.