Hate waiting for SASS compiling your stylesheets with Compass over 10 seconds everytime? C6 helps you write style sheets with efficiency.

C6 is a SASS compatible implementation written in Go. But wait! this is not only to implement SASS, but also to improve the language for better consistency, syntax and performance. And yes, this means we're free to accept new language feature requests.

Setup GOPATH:

source goenv

Setup dependencies:

source goinstall

Run tests:

go test c6
go test -v c6
go test -v c6/ast

To run specific test

go test -run TestParser -x -v c6

• Lexing

  • @import
  • simple selector.
    • type selector.
    • child selector.
    • attribute selector.
    • adjacent selector.
    • descendant selector.
    • class selector.
    • ID selector.
  • Ruleset
  • Sub-ruleset
  • Interpolation
  • Property name
  • Property value list
  • Comma-separated list
  • Space-separated list
  • @if , @else , @else if
  • Flags: !default, !important, !optional, !global
  • Hex color
  • Functions
  • Vendor prefix properties
  • MS filter. progid:DXImageTransform.Microsoft....
  • Variable names
  • Variable assignment
  • Time unit support. s second, ms ... etc
  • Angle unit support.
  • Resolution unit support.
  • Unicode Range support: https://developer.mozilla.org/en-US/docs/Web/CSS/unicode-range
  • Media Query

• Syntax

  • built-in @import-once

• Built-in Functions

  • .... to be listed

• Parser

  • Parse @import
  • Parse Expression
  • Parse Space-Sep List
  • Parse Comma-Sep List
  • Parse Map (tests required)
  • Parse Selector
  • Parse Selector with interpolation
  • Parse RuleSet
  • Parse DeclarationBlock
  • Parse Variable Assignment Statement
  • Parse PropertyName
  • Parse PropertyName with interpolation
  • Parse PropertyValue
  • Parse PropertyValue with interpolation
  • Parse conditions
  • Parse Nested RuleSet
  • Parse options: !default, !global, !optional
  • Parse CSS Hack for different browser (support more syntax sugar for this)
  • Parse @font-face block
  • Parse @if statement
  • Parse @mixin statement
  • Parse @include statement
  • Parse @function statement
  • Parse keyword arguments for @function
  • Parse @media statement
  • Parse @switch statement
  • Parse @case statement
  • Parse @use statement

• SASS Built-in Functions

  • RGB functions
    • rgb($red, $green, $blue)
    • rgba($red, $green, $blue, $alpha)
    • red($color)
    • green($color)
    • blue($color)
    • mix($color1, $color2, [$weight])
  • HSL Functions
    • hsl($hue, $saturation, $lightness)
    • hsla($hue, $saturation, $lightness, $alpha)
    • hue($color)
    • saturation($color)
    • lightness($color)
    • adjust-hue($color, $degrees)
    • lighten($color, $amount)
    • darken($color, $amount)
    • saturate($color, $amount)
    • desaturate($color, $amount)
    • grayscale($color)
    • complement($color)
    • invert($color)
  • Opacity Functions
    • alpha($color) / opacity($color)
    • rgba($color, $alpha)
    • opacify($color, $amount) / fade-in($color, $amount)
    • transparentize($color, $amount) / fade-out($color, $amount)
  • Other Color Functions
    • adjust-color($color, [$red], [$green], [$blue], [$hue], [$saturation], [$lightness], [$alpha])
    • scale-color($color, [$red], [$green], [$blue], [$saturation], [$lightness], [$alpha])
    • change-color($color, [$red], [$green], [$blue], [$hue], [$saturation], [$lightness], [$alpha])
    • ie-hex-str($color)
  • String Functions
    • unquote($string)
    • quote($string)
    • str-length($string)
    • str-insert($string, $insert, $index)
    • str-index($string, $substring)
    • str-slice($string, $start-at, [$end-at])
    • to-upper-case($string)
    • to-lower-case($string)
  • Number Functions
    • percentage($number)
    • round($number)
    • ceil($number)
    • floor($number)
    • abs($number)
    • min($numbers…)
    • max($numbers…)
    • random([$limit])
  • List Functions
    • length($list)
    • nth($list, $n)
    • set-nth($list, $n, $value)
    • join($list1, $list2, [$separator])
    • append($list1, $val, [$separator])
    • zip($lists…)
    • index($list, $value)
    • list-separator(#list)
  • Map Functions
    • map-get($map, $key)
    • map-merge($map1, $map2)
    • map-remove($map, $keys…)
    • map-keys($map)
    • map-values($map)
    • map-has-key($map, $key)
    • keywords($args)
  • Selector Functions
    • .... to be expanded ...

• Building AST

  • RuleSet
  • DeclarationBlock
  • PropertyName
  • PropertyValue
  • Comma-Separated List
  • Space-Separated List
  • Basic Expressions
  • FunctionCall
  • Expression with interpolation
  • Variable statements
  • If Condition
  • If Else If, Else Condition
  • Built-in color keyword table
  • Hex Color computation
  • HSL Color computation
  • Number operation: add, sub, mul, div
  • Length operation: number operation for px, pt, em, rem, cm ...etc
  • Expression evaluation
  • Boolean expression evaluation
  • Media Query conditions

• CodeGen

  • NestedStyleCompiler
    • .... list ast nodes here ....

SASS Reference http://sass-lang.com/documentation/file.SASS_REFERENCE.html

A feature check list from libsass:

• https://github.com/sass/libsass/releases/tag/3.2.0
• sass/sass#1094

Grammar Ambiguity https://www.facebook.com/cindylinz/posts/10202186527405801?hc_location=ufi

• Slack: we are on Slack channel #c6, go invite yourself here: https://docs.google.com/forms/d/11KpalZc6AUuQYf7vz531ys0pLEC9csjkC6QyC_hJQEg/viewform

• Our Official Twitter Channel: https://twitter.com/C6SASS

MPL License https://www.mozilla.org/MPL/2.0/

(MPL is like LGPL but with static/dynamic linking exception, which allows you to either dynamic/static link this library without permissions)