Sass Changelog

Table of contents {:toc}

3.0.0.beta.4

Sass Property Syntax

New-style properties (with the colon after the name) in the indented syntax now allow whitespace before the colon. For example:

foo
  color : blue

Minor Changes

Running sass-convert --from sass --to sass will raise an error unless --in-place is provided, to prevent accidental erasure of source files.

Bug Fixes

Variables are now allowed as arguments to url().
#{} interpolation is now allowed within url().
url()s within Sass2 properties are properly converted to Sass 3 or SCSS now.
Don't consider e.g. foo ($bar + $baz) to be a function call. Function calls can't have whitespace between the name and the parentheses.
Allow interpolation in Sass properties to contain spaces.
Don't crash with odd HSL errors for some color functions.

3.0.0.beta.3

Tagged on GitHub.

`@import` in Sass

The Sass @import statement now allows non-CSS files to be specified with quotes, for similarity with the SCSS syntax. For example, @import "foo.sass" Will now import the foo.sass file, rather than compiling to @import "foo.sass";.

Bug Fixes

Make sure nested comments use the proper prefix when sass-convert outputs Sass.
Allow comments to begin with * in all cases.

3.0.0.beta.2

Tagged on GitHub.

Stylesheet Updating Speed

Several caching layers were added to Sass's stylesheet updater. This means that it should run significantly faster. This benefit will be seen by people using Sass in development mode with Rails, Rack, and Merb, as well as people using sass --watch from the command line, and to a lesser (but still significant) extent sass --update. Thanks to thedarkone.

New Sass Functions for Introspection

Several new functions were added to make it easier to have more flexible arguments to mixins and to enable deprecation of obsolete APIs.

{Sass::Script::Functions#type_of type-of} -- Returns the type of a value.
{Sass::Script::Functions#unit unit} -- Returns the units associated with a number.
{Sass::Script::Functions#unitless unitless} -- Returns whether a number has units or not.
{Sass::Script::Functions#comparable comparable} -- Returns whether two numbers can be added or compared.

`@warn`

A new directive @warn has been added that allows Sass libraries to emit warnings. This can be used to issue deprecation warnings, discourage sloppy use of mixins, etc. @warn takes a single argument: a SassScript expression that will be displayed on the console along with a stylesheet trace for locating the warning. For example:

@mixin blue-text {
  @warn "The blue-text mixin is deprecated. Use new-blue-text instead.";
  color: #00f;
}

Warnings may be silenced with the new --quiet command line option, or the corresponding {file:SASS_REFERENCE.md#quiet-option :quiey Sass option}. This option will also affect warnings printed by Sass itself. Warnings are off by default in the Rails, Rack, and Merb production environments.

`sass-convert`

`--recursive`

A --recursive option has been added that allows sass-convert to convert an entire directory of files. --recursive requires that both the --from and --to flags are specified. For example:

# Convert all .sass files in stylesheets/ to SCSS.
# "sass2" means that these files are assumed to use the Sass 2 syntax.
$ sass-convert --recursive --from sass2 --to scss stylesheets/

`--dasherize`

The --dasherize options converts all underscores to hyphens, which are now allowed as part of identifiers in Sass. Note that since underscores may still be used in place of hyphens when referring to mixins and variables, this won't cause any backwards-incompatibilities.

Sass Comment Format

When converting to the indented syntax, each line of comments past the first begins with either // (for Sass comments) or * (for CSS comments). This prevents some whitespace errors.

Minor Changes

Indented-syntax /* comments may now include * on lines beyond the first, which will get stripped out of the output. This means that the following will render nicely:

/* Foo
 * Bar
 * Baz

Bug Fixes

Include ; when rendering nested properties.
Interpolation is allowed immediately following ., #, and : in selectors, as well as in attribute selector names.
Interpolation works even when there's only a hyphen separating two interpolation sections, as in -foo-#{$a}-#{$b}.
Properly parse the #name: value Safari hack.
When converting from Sass 2, empty strings as variable values are preserved.
#{} interpolation within strings will now be converted properly to #{} interpolation within strings.
Don't double-escape backslashes in strings.
Perform all conversions to rules within directive blocks when converting CSS.
Prevent multiline CSS selectors from getting cut off in certain rare cases.
Improve the parsing of mixin argument lists. This mostly means that error messages will be clearer.

CSS Parsing

The proprietary Microsoft alpha(opacity=20) syntax is now correctly parsed.

Bug Fixes

Don't die when using --watch under certain Windows configurations.
Fix an exception that was raised when using the :debug_info option with Ruby 1.9.

3.0.0.beta.1

Tagged on GitHub.

Deprecations -- Must Read!

{#3-0-0-deprecations}

Using = for SassScript properties and variables is deprecated, and will be removed in Sass 3.2. Use : instead. See also this changelog entry
Because of the above, property values using : will be parsed more thoroughly than they were before. Although all valid CSS3 properties as well as most hacks and proprietary syntax should be supported, it's possible that some properties will break. If this happens, please report it to the Sass mailing list.
In addition, setting the default value of variables with ||= is now deprecated and will be removed in Sass 3.2. Instead, add !default to the end of the value. See also this changelog entry
The ! prefix for variables is deprecated, and will be removed in Sass 3.2. Use $ as a prefix instead. See also this changelog entry.
The css2sass command-line tool has been deprecated, and will be removed in Sass 3.2. Use the new sass-convert tool instead. See also this changelog entry.

SCSS (Sassy CSS)

Sass 3 introduces a new syntax known as SCSS which is fully compatible with the syntax of CSS3, while still supporting the full power of Sass. This means that every valid CSS3 stylesheet is a valid SCSS file with the same meaning. In addition, SCSS understands most CSS hacks and vendor-specific syntax, such as IE's old filter syntax.

SCSS files use the .scss extension. They can import .sass files, and vice-versa. Their syntax is fully described in the {file:SASS_REFERENCE.md Sass reference}; if you're already familiar with Sass, though, you may prefer the {file:SCSS_FOR_SASS_USERS.md intro to SCSS for Sass users}.

Since SCSS is a much more approachable syntax for those new to Sass, it will be used as the default syntax for the reference, as well as for most other Sass documentation. The indented syntax will continue to be fully supported, however.

Sass files can be converted to SCSS using the new sass-convert command-line tool. For example:

# Convert a Sass file to SCSS
$ sass-convert style.sass style.scss

Note that if you're converting a Sass file written for Sass 2, you should use the --from sass2 flag. For example:

# Convert a Sass file to SCSS
$ sass-convert --from sass2 style.sass style.scss

# Convert all Sass files to SCSS
$ sass-convert --recursive --in-place --from sass2 --to scss stylesheets/

Syntax Changes {#3-0-0-syntax-changes}

SassScript Context

{#3-0-0-sass-script-context}

The = character is no longer required for properties that use SassScript (that is, variables and operations). All properties now use SassScript automatically; this means that : should be used instead. Variables should also be set with :. For example, what used to be

// Indented syntax
.page
  color = 5px + 9px

should now be

// Indented syntax
.page
  color: 5px + 9px

This means that SassScript is now an extension of the CSS3 property syntax. All valid CSS3 properties are valid SassScript, and will compile without modification (some invalid properties work as well, such as Microsoft's proprietary filter syntax). This entails a few changes to SassScript to make it fully CSS3-compatible, which are detailed below.

This also means that Sass will now be fully parsing all property values, rather than passing them through unchanged to the CSS. Although care has been taken to support all valid CSS3, as well as hacks and proprietary syntax, it's possible that a property that worked in Sass 2 won't work in Sass 3. If this happens, please report it to the Sass mailing list.

Note that if = is used, SassScript will be interpreted as backwards-compatibly as posssible. In particular, the changes listed below don't apply in an = context.

The sass-convert command-line tool can be used to upgrade Sass files to the new syntax using the --in-place flag. For example:

# Upgrade style.sass:
$ sass-convert --in-place style.sass

# Upgrade all Sass files:
$ sass-convert --recursive --in-place --from sass2 --to sass stylesheets/

Quoted Strings

Quoted strings (e.g. "foo") in SassScript now render with quotes. In addition, unquoted strings are no longer deprecated, and render without quotes. This means that almost all strings that had quotes in Sass 2 should not have quotes in Sass 3.

Although quoted strings render with quotes when used with :, they do not render with quotes when used with #{}. This allows quoted strings to be used for e.g. selectors that are passed to mixins.

Strings can be forced to be quoted and unquoted using the new {Sass::Script::Functions#unquote unquote} and {Sass::Script::Functions#quote quote} functions.

Division and `/`

Two numbers separated by a / character are allowed as property syntax in CSS, e.g. for the font property. SassScript also uses / for division, however, which means it must decide what to do when it encounters numbers separated by /.

For CSS compatibility, SassScript does not perform division by default. However, division will be done in almost all cases where division is intended. In particular, SassScript will perform division in the following three situations:

If the value, or any part of it, is stored in a variable.
If the value is surrounded by parentheses.
If the value is used as part of another arithmetic expression.

For example:

p
  font: 10px/8px
  $width: 1000px
  width: $width/2
  height: (500px/2)
  margin-left: 5px + 8px/2px

is compiled to:

p {
  font: 10px/8px;
  width: 500px;
  height: 250px;
  margin-left: 9px; }

Variable Defaults

Since = is no longer used for variable assignment, assigning defaults to variables with ||= no longer makes sense. Instead, the !default flag should be added to the end of the variable value. This syntax is meant to be similar to CSS's !important flag. For example:

$var: 12px !default;

Variable Prefix Character

{#3-0-0-dollar-prefix}

The Sass variable character has been changed from ! to the more aesthetically-appealing $. For example, what used to be

!width = 13px
.icon
  width = !width

should now be

$width: 13px
.icon
  width: $width

The sass-convert command-line tool can be used to upgrade Sass files to the new syntax using the --in-place flag. For example:

# Upgrade style.sass:
$ sass-convert --in-place style.sass

# Upgrade all Sass files:
$ sass-convert --recursive --in-place --from sass2 --to sass stylesheets/

! may still be used, but it's deprecated and will print a warning. It will be removed in the next version of Sass, 3.2.

Variable and Mixin Names

SassScript variable and mixin names may now contain hyphens. In fact, they may be any valid CSS3 identifier. For example:

$prettiest-color: #542FA9
=pretty-text
  color: $prettiest-color

In order to allow frameworks like Compass to use hyphens in variable names while maintaining backwards-compatibility, variables and mixins using hyphens may be referred to with underscores, and vice versa. For example:

$prettiest-color: #542FA9
.pretty
  // Using an underscore instead of a hyphen works
  color: $prettiest_color

Single-Quoted Strings

SassScript now supports single-quoted strings. They behave identically to double-quoted strings, except that single quotes need to be backslash-escaped and double quotes do not.

Mixin Definition and Inclusion

Sass now supports the @mixin directive as a way of defining mixins (like =), as well as the @include directive as a way of including them (like +). The old syntax is not deprecated, and the two are fully compatible. For example:

@mixin pretty-text
  color: $prettiest-color

a
  @include pretty-text

is the same as:

=pretty-text
  color: $prettiest-color

a
  +pretty-text

Colors

SassScript color values are much more powerful than they were before. Support was added for alpha channels, and most of Chris Eppstein's compass-colors plugin was merged in, providing color-theoretic functions for modifying colors.

One of the most interesting of these functions is {Sass::Script::Functions#mix mix}, which mixes two colors together. This provides a much better way of combining colors and creating themes than standard color arithmetic.

Alpha Channels

Sass now supports colors with alpha channels, constructed via the {Sass::Script::Functions#rgba rgba} and {Sass::Script::Functions#hsla hsla} functions. Alpha channels are unaffected by color arithmetic. However, the {Sass::Script::Functions#opacify opacify} and {Sass::Script::Functions#transparentize transparentize} functions allow colors to be made more and less opaque, respectively.

Sass now also supports functions that return the values of the {Sass::Script::Functions#red red}, {Sass::Script::Functions#blue blue}, {Sass::Script::Functions#green green}, and {Sass::Script::Functions#alpha alpha} components of colors.

HSL Colors

Sass has many new functions for using the HSL values of colors. For an overview of HSL colors, check out the CSS3 Spec. All these functions work just as well on RGB colors as on colors constructed with the {Sass::Script::Functions#hsl hsl} function.

The {Sass::Script::Functions#lighten lighten} and {Sass::Script::Functions#darken darken} functions adjust the lightness of a color.
The {Sass::Script::Functions#saturate saturate} and {Sass::Script::Functions#desaturate desaturate} functions adjust the saturation of a color.
The {Sass::Script::Functions#adjust_hue adjust-hue} function adjusts the hue of a color.
The {Sass::Script::Functions#hue hue}, {Sass::Script::Functions#saturation saturation}, and {Sass::Script::Functions#lightness lightness} functions return the corresponding HSL values of the color.
The {Sass::Script::Functions#grayscale grayscale} function converts a color to grayscale.
The {Sass::Script::Functions#complement complement} function returns the complement of a color.

Watching for Updates

{#3-0-0-watch}

The sass command-line utility has a new flag: --watch. sass --watch monitors files or directories for updated Sass files and compiles those files to CSS automatically. This will allow people not using Ruby or Compass to use Sass without having to manually recompile all the time.

Here's the syntax for watching a directory full of Sass files:

sass --watch app/stylesheets:public/stylesheets

This will watch every Sass file in app/stylesheets. Whenever one of them changes, the corresponding CSS file in public/stylesheets will be regenerated. Any files that import that file will be regenerated, too.

The syntax for watching individual files is the same:

sass --watch style.sass:out.css

You can also omit the output filename if you just want it to compile to name.css. For example:

sass --watch style.sass

This will update style.css whenever style.sass changes.

You can list more than one file and/or directory, and all of them will be watched:

sass --watch foo/style:public/foo bar/style:public/bar
sass --watch screen.sass print.sass awful-hacks.sass:ie.css
sass --watch app/stylesheets:public/stylesheets public/stylesheets/test.sass

File and directory watching is accessible from Ruby, using the {Sass::Plugin#watch} function.

Bulk Updating

Another new flag for the sass command-line utility is --update. It checks a group of Sass files to see if their CSS needs to be updated, and updates if so.

The syntax for --update is just like watch:

sass --update app/stylesheets:public/stylesheets
sass --update style.sass:out.css
sass --watch screen.sass print.sass awful-hacks.sass:ie.css

In fact, --update work exactly the same as --watch, except that it doesn't continue watching the files after the first check.

`sass-convert` (née `css2sass`) {#3-0-0-sass-convert}

The sass-convert tool, which used to be known as css2sass, has been greatly improved in various ways. It now uses a full-fledged CSS3 parser, so it should be able to handle any valid CSS3, as well as most hacks and proprietary syntax.

sass-convert can now convert between Sass and SCSS. This is normally inferred from the filename, but it can also be specified using the --from and --to flags. For example:

$ generate-sass | sass-convert --from sass --to scss | consume-scss

It's also now possible to convert a file in-place -- that is, overwrite the old file with the new file. This is useful for converting files in the Sass 2 syntax to the new Sass 3 syntax, e.g. by doing sass-convert --in-place --from sass2 style.sass.

Error Handling

Several bug fixes and minor improvements have been made, including:

Fixing line-number reporting for errors on the last line of templates that didn't have trailing newlines.
Only displaying the text for the current line when reporting CSS parsing errors.
Displaying the expected strings as strings rather than regular expressions whenever possible.

Error Backtraces

Numerous bugs were fixed with the backtraces given for Sass errors, especially when importing files and using mixins. All imports and mixins will now show up in the Ruby backtrace, with the proper filename and line number.

In addition, when the sass executable encounters an error, it now prints the filename where the error occurs, as well as a backtrace of Sass imports and mixins.

Formatting

Properties of the form

margin: auto
  top: 10px
  bottom: 20px

That is, properties with a value and also nested properties, are now rendered as such in nested output mode:

margin: auto;
  margin-top: 10px;
  margin-bottom: 20px;

That is, with the nested properties indented in the source.

Ruby 1.9 Support

Sass and css2sass now produce more descriptive errors when given a template with invalid byte sequences for that template's encoding, including the line number and the offending character.
Sass and css2sass now accept Unicode documents with a byte-order-mark.

Rack Support

The Sass Rails plugin now works using Rack middleware by default in versions of Rails that support it (2.3 and onwards).

Firebug Support

A new {file:SASS_REFERENCE.md#debug_info-option :debug_info option} has been added that emits line-number and filename information to the CSS file in a browser-readable format. This can be used with the new FireSass Firebug extension to report the Sass filename and line number for generated CSS files.

This is also available via the --debug-info command-line flag.

Rip Support

Haml is now compatible with the Rip package management system. Thanks to Josh Peek.

Sass::Plugin Callbacks

{Sass::Plugin} now has a large collection of callbacks that allow users to run code when various actions are performed. For example:

Sass::Plugin.on_updating_stylesheet do |template, css|
  puts "#{template} has been compiled to #{css}!"
end

For a full list of callbacks and usage notes, see the {Sass::Plugin} documentation.

`:compressed` Style

When the :compressed style is used, colors will be output as the minimal possible representation. This means whichever is smallest of the HTML4 color name and the hex representation (shortened to the three-letter version if possible).

Minor Changes

If a CSS or Sass function is used that has the name of a color, it will now be parsed as a function rather than as a color. For example, fuchsia(12) now renders as fuchsia(12) rather than fuchsia 12, and tealbang(12) now renders as tealbang(12) rather than teal bang(12).

2.2.24 (Unreleased)

Parent references -- the & character -- may only be placed at the beginning of simple selector sequences in Sass 3. Placing them elsewhere is deprecated in 2.2.24 and will print a warning. For example, foo &.bar is allowed, but foo .bar& is not.

2.2.23

Tagged on GitHub.

Don't crash when rake gems is run in Rails with Sass installed. Thanks to Florian Frank.
When raising a file-not-found error, add a list of load paths that were checked.
If an import isn't found for a cached Sass file and the {file:SASS_REFERENCE.md#full_exception :full_exception option} is enabled, print the full exception rather than raising it.
Fix a bug with a weird interaction with Haml, DataMapper, and Rails 3 that caused some tag helpers to go into infinite recursion.

2.2.22

Tagged on GitHub.

Add a railtie so Haml and Sass will be automatically loaded in Rails 3. Thanks to Daniel Neighman.
Make loading the gemspec not crash on read-only filesystems like Heroku's.

2.2.21

Tagged on GitHub.

Fix a few bugs in the git-revision-reporting in {Haml::Version#version}. In particular, it will still work if git gc has been called recently, or if various files are missing.
Always use __FILE__ when reading files within the Haml repo in the Rakefile. According to this bug report, this should make Sass work better with Bundler.

2.2.20

Tagged on GitHub.

If the cache file for a given Sass file is corrupt because it doesn't have enough content, produce a warning and read the Sass file rather than letting the exception bubble up. This is consistent with other sorts of sassc corruption handling.
Calls to defined? shouldn't interfere with Rails' autoloading in very old versions (1.2.x).

2.2.19

Tagged on GitHub.

There were no changes made to Sass between versions 2.2.18 and 2.2.19.

2.2.18

Tagged on GitHub.

Use Rails.env rather than RAILS_ENV when running under Rails 3.0. Thanks to Duncan Grazier.
Support :line_numbers as an alias for {file:SASS_REFERENCE.md#line_numbers-option :line_comments}, since that's what the docs have said forever. Similarly, support --line-numbers as a command-line option.
Add a --unix-newlines flag to all executables for outputting Unix-style newlines on Windows.
Add a {file:SASS_REFERENCE.md#unix_newlines-option :unix_newlines option} for {Sass::Plugin} for outputting Unix-style newlines on Windows.
Fix the --cache-location flag, which was previously throwing errors. Thanks to tav.
Allow comments at the beginning of the document to have arbitrary indentation, just like comments elsewhere. Similarly, comment parsing is a little nicer than before.

2.2.17

Tagged on GitHub.

When the {file:SASS_REFERENCE.md#full_exception-option :full_exception option} is false, raise the error in Ruby code rather than swallowing it and printing something uninformative.
Fixed error-reporting when something goes wrong when loading Sass using the sass executable. This used to raise a NameError because Sass::SyntaxError wasn't defined. Now it'll raise the correct exception instead.
Report the filename in warnings about selectors without properties.
nil values for Sass options are now ignored, rather than raising errors.
Fix a bug that appears when Plugin template locations have multiple trailing slashes. Thanks to Jared Grippe.

Must Read!

When @import is given a filename without an extension, the behavior of rendering a CSS @import if no Sass file is found is deprecated. In future versions, @import foo will either import the template or raise an error.

2.2.16

Tagged on GitHub.

Fixed a bug where modules containing user-defined Sass functions weren't made available when simply included in {Sass::Script::Functions} ({Sass::Script::Functions Functions} needed to be re-included in {Sass::Script::Functions::EvaluationContext Functions::EvaluationContext}). Now the module simply needs to be included in {Sass::Script::Functions}.

2.2.15

Tagged on GitHub.

Added {Sass::Script::Color#with} for a way of setting color channels that's easier than manually constructing a new color and is forwards-compatible with alpha-channel colors (to be introduced in Sass 2.4).
Added a missing require in Sass that caused crashes when it was being run standalone.

2.2.14

Tagged on GitHub.

All Sass functions now raise explicit errors if their inputs are of the incorrect type.
Allow the SassScript rgb() function to take percentages in addition to numerical values.
Fixed a bug where SassScript strings with # followed by #{} interpolation didn't evaluate the interpolation.

SassScript Ruby API

These changes only affect people defining their own Sass functions using {Sass::Script::Functions}.

{Sass::Script::Color#value} attribute is deprecated. Use {Sass::Script::Color#rgb} instead. The returned array is now frozen as well.
Add an assert_type function that's available to {Sass::Script::Functions}. This is useful for typechecking the inputs to functions.

Rack Support

Sass 2.2.14 includes Rack middleware for running Sass, meaning that all Rack-enabled frameworks can now use Sass. To activate this, just add

require 'sass/plugin/rack'
use Sass::Plugin::Rack

to your config.ru. See the {Sass::Plugin::Rack} documentation for more details.

2.2.13

Tagged on GitHub.

There were no changes made to Sass between versions 2.2.12 and 2.2.13.

2.2.12

Tagged on GitHub.

Fix a stupid bug introduced in 2.2.11 that broke the Sass Rails plugin.

2.2.11

Tagged on GitHub.

Added a note to errors on properties that could be pseudo-classes (e.g. :focus) indicating that they should be backslash-escaped.
Automatically interpret properties that could be pseudo-classes as such if {file:SASS_REFERENCE.md.html#property_syntax-option :property_syntax} is set to :new.
Fixed css2sass's generation of pseudo-classes so that they're backslash-escaped.
Don't crash if the Haml plugin skeleton is installed and rake gems:install is run.
Don't use RAILS_ROOT directly. This no longer exists in Rails 3.0. Instead abstract this out as Haml::Util.rails_root. This changes makes Haml fully compatible with edge Rails as of this writing.
Make use of a Rails callback rather than a monkeypatch to check for stylesheet updates in Rails 3.0+.

2.2.10

Tagged on GitHub.

Add support for attribute selectors with spaces around the =. For example:
```
a[href = http://google.com]
  color: blue
```

2.2.9

Tagged on GitHub.

There were no changes made to Sass between versions 2.2.8 and 2.2.9.

2.2.8

Tagged on GitHub.

There were no changes made to Sass between versions 2.2.7 and 2.2.8.

2.2.7

Tagged on GitHub.

There were no changes made to Sass between versions 2.2.6 and 2.2.7.

2.2.6

Tagged on GitHub.

Don't crash when the __FILE__ constant of a Ruby file is a relative path, as apparently happens sometimes in TextMate (thanks to Karl Varga).
Add "Sass" to the --version string for the executables.

2.2.5

Tagged on GitHub.

There were no changes made to Sass between versions 2.2.4 and 2.2.5.

2.2.4

Tagged on GitHub.

Don't add require 'rubygems' to the top of init.rb when installed via sass --rails. This isn't necessary, and actually gets clobbered as soon as haml/template is loaded.
Document the previously-undocumented {file:SASS_REFERENCE.md#line-option :line option}, which allows the number of the first line of a Sass file to be set for error reporting.

2.2.3

Tagged on GitHub.

Sass 2.2.3 prints line numbers for warnings about selectors with no properties.

2.2.2

Tagged on GitHub.

Sass 2.2.2 is a minor bug-fix release. Notable changes include better parsing of mixin definitions and inclusions and better support for Ruby 1.9.

2.2.1

Tagged on GitHub.

Sass 2.2.1 is a minor bug-fix release.

Must Read!

It used to be acceptable to use - immediately following variable names, without any whitespace in between (for example, !foo-!bar). This is now deprecated, so that in the future variables with hyphens can be supported. Surround - with spaces.

2.2.0

Tagged on GitHub.

The 2.2 release marks a significant step in the evolution of the Sass language. The focus has been to increase the power of Sass to keep your stylesheets maintainable by allowing new forms of abstraction to be created within your stylesheets and the stylesheets provided by others that you can download and import into your own. The fundamental units of abstraction in Sass are variables and mixins. Please read below for a list of changes:

Must Read!

Sass Comments (//) used to only comment out a single line. This was deprecated in 2.0.10 and starting in 2.2, Sass comments will comment out any lines indented under them. Upgrade to 2.0.10 in order to see deprecation warnings where this change affects you.
Implicit Strings within SassScript are now deprecated and will be removed in 2.4. For example: border= !width solid #00F should now be written as border: #{!width} solid #00F or as border= !width "solid" #00F. After upgrading to 2.2, you will see deprecation warnings if you have sass files that use implicit strings.

Sass Syntax Changes

Flexible Indentation

The indentation of Sass documents is now flexible. The first indent that is detected will determine the indentation style for that document. Tabs and spaces may never be mixed, but within a document, you may choose to use tabs or a flexible number of spaces.

Multiline Sass Comments

Sass Comments (//) will now comment out whatever is indented beneath them. Previously they were single line when used at the top level of a document. Upgrading to the latest stable version will give you deprecation warnings if you have silent comments with indentation underneath them.

Mixin Arguments

Sass Mixins now accept any number of arguments. To define a mixin with arguments, specify the arguments as a comma-delimited list of variables like so:

=my-mixin(!arg1, !arg2, !arg3)

As before, the definition of the mixin is indented below the mixin declaration. The variables declared in the argument list may be used and will be bound to the values passed to the mixin when it is invoked. Trailing arguments may have default values as part of the declaration:

=my-mixin(!arg1, !arg2 = 1px, !arg3 = blue)

In the example above, the mixin may be invoked by passing 1, 2 or 3 arguments to it. A similar syntax is used to invoke a mixin that accepts arguments:

div.foo
  +my-mixin(1em, 3px)

When a mixin has no required arguments, the parenthesis are optional.

The default values for mixin arguments are evaluated in the global context at the time when the mixin is invoked, they may also reference the previous arguments in the declaration. For example:

!default_width = 30px
=my-fancy-mixin(!width = !default_width, !height = !width)
  width= !width
  height= !height

.default-box
  +my-fancy-mixin

.square-box
  +my-fancy-mixin(50px)

.rectangle-box
  +my-fancy-mixin(25px, 75px)

!default_width = 10px
.small-default-box
  +my-fancy-mixin

compiles to:

.default-box {
  width: 30px;
  height: 30px; }

.square-box {
  width: 50px;
  height: 50px; }

.rectangle-box {
  width: 25px;
  height: 75px; }

.small-default-box {
  width: 10px;
  height: 10px; }

Sass, Interactive

The sass command line option -i now allows you to quickly and interactively experiment with SassScript expressions. The value of the expression you enter will be printed out after each line. Example:

$ sass -i
>> 5px
5px
>> 5px + 10px
15px
>> !five_pixels = 5px
5px
>> !five_pixels + 10px
15px

SassScript

The features of SassScript have been greatly enhanced with new control directives, new fundamental data types, and variable scoping.

New Data Types

SassScript now has four fundamental data types:

Number
String
Boolean (New in 2.2)
Colors

More Flexible Numbers

Like JavaScript, SassScript numbers can now change between floating point and integers. No explicit casting or decimal syntax is required. When a number is emitted into a CSS file it will be rounded to the nearest thousandth, however the internal representation maintains much higher precision.

Improved Handling of Units

While Sass has long supported numbers with units, it now has a much deeper understanding of them. The following are examples of legal numbers in SassScript:

0, 1000, 6%, -2px, 5pc, 20em, or 2foo.

Numbers of the same unit may always be added and subtracted. Numbers that have units that Sass understands and finds comparable, can be combined, taking the unit of the first number. Numbers that have non-comparable units may not be added nor subtracted -- any attempt to do so will cause an error. However, a unitless number takes on the unit of the other number during a mathematical operation. For example:

>> 3mm + 4cm
43mm
>> 4cm + 3mm
4.3cm
>> 3cm + 2in
8.08cm
>> 5foo + 6foo
11foo
>> 4% + 5px
SyntaxError: Incompatible units: 'px' and '%'.
>> 5 + 10px
15px

Sass allows compound units to be stored in any intermediate form, but will raise an error if you try to emit a compound unit into your css file.

>> !em_ratio = 1em / 16px
0.063em/px
>> !em_ratio * 32px
2em
>> !em_ratio * 40px
2.5em

Colors

A color value can be declared using a color name, hexadecimal, shorthand hexadecimal, the rgb function, or the hsl function. When outputting a color into css, the color name is used, if any, otherwise it is emitted as hexadecimal value. Examples:

> #fff
white
>> white
white
>> #FFFFFF
white
>> hsl(180, 100, 100)
white
>> rgb(255, 255, 255)
white
>> #AAA
#aaaaaa

Math on color objects is performed piecewise on the rgb components. However, these operations rarely have meaning in the design domain (mostly they make sense for gray-scale colors).

>> #aaa + #123
#bbccdd
>> #333 * 2
#666666

Booleans

Boolean objects can be created by comparison operators or via the true and false keywords. Booleans can be combined using the and, or, and not keywords.

>> true
true
>> true and false
false
>> 5 < 10
true
>> not (5 < 10)
false
>> not (5 < 10) or not (10 < 5)
true
>> 30mm == 3cm
true
>> 1px == 1em
false

Strings

Unicode escapes are now allowed within SassScript strings.

Control Directives

New directives provide branching and looping within a sass stylesheet based on SassScript expressions. See the Sass Reference for complete details.

@for

The @for directive loops over a set of numbers in sequence, defining the current number into the variable specified for each loop. The through keyword means that the last iteration will include the number, the to keyword means that it will stop just before that number.

@for !x from 1px through 5px
  .border-#{!x}
    border-width= !x

compiles to:

.border-1px {
  border-width: 1px; }

.border-2px {
  border-width: 2px; }

.border-3px {
  border-width: 3px; }

.border-4px {
  border-width: 4px; }

.border-5px {
  border-width: 5px; }

@if / @else if / @else

The branching directives @if, @else if, and @else let you select between several branches of sass to be emitted, based on the result of a SassScript expression. Example:

!type = "monster"
p
  @if !type == "ocean"
    color: blue
  @else if !type == "matador"
    color: red
  @else if !type == "monster"
    color: green
  @else
    color: black

is compiled to:

p {
  color: green; }

@while

The @while directive lets you iterate until a condition is met. Example:

!i = 6
@while !i > 0
  .item-#{!i}
    width = 2em * !i
  !i = !i - 2

is compiled to:

.item-6 {
  width: 12em; }

.item-4 {
  width: 8em; }

.item-2 {
  width: 4em; }

Variable Scoping

The term "constant" has been renamed to "variable." Variables can be declared at any scope (a.k.a. nesting level) and they will only be visible to the code until the next outdent. However, if a variable is already defined in a higher level scope, setting it will overwrite the value stored previously.

In this code, the !local_var variable is scoped and hidden from other higher level scopes or sibling scopes:

.foo
  .bar
    !local_var = 1px
    width= !local_var
  .baz
    // this will raise an undefined variable error.
    width= !local_var
  // as will this
  width= !local_var

In this example, since the !global_var variable is first declared at a higher scope, it is shared among all lower scopes:

!global_var = 1px
.foo
  .bar
    !global_var = 2px
    width= !global_var
  .baz
    width= !global_var
  width= !global_var

compiles to:

.foo {
  width: 2px; }
  .foo .bar {
    width: 2px; }
  .foo .baz {
    width: 2px; }

Interpolation

Interpolation has been added. This allows SassScript to be used to create dynamic properties and selectors. It also cleans up some uses of dynamic values when dealing with compound properties. Using interpolation, the result of a SassScript expression can be placed anywhere:

!x = 1
!d = 3
!property = "border"
div.#{!property}
  #{!property}: #{!x + !d}px solid
  #{!property}-color: blue

is compiled to:

div.border {
  border: 4px solid;
  border-color: blue; }

Sass Functions

SassScript defines some useful functions that are called using the normal CSS function syntax:

p
  color = hsl(0, 100%, 50%)

is compiled to:

#main {
  color: #ff0000; }

The following functions are provided: hsl, percentage, round, ceil, floor, and abs. You can define additional functions in ruby.

See {Sass::Script::Functions} for more information.

New Options

`:line_comments`

To aid in debugging, You may set the :line_comments option to true. This will cause the sass engine to insert a comment before each selector saying where that selector was defined in your sass code.

`:template_location`

The {Sass::Plugin} :template_location option now accepts a hash of sass paths to corresponding css paths. Please be aware that it is possible to import sass files between these separate locations -- they are not isolated from each other.

Miscellaneous Features

`@debug` Directive

The @debug directive accepts a SassScript expression and emits the value of that expression to the terminal (stderr).

Example:

@debug 1px + 2px

During compilation the following will be printed:

Line 1 DEBUG: 3px

Ruby 1.9 Support

Sass now fully supports Ruby 1.9.1.

Sass Cache

By default, Sass caches compiled templates and partials. This dramatically speeds up re-compilation of large collections of Sass files, and works best if the Sass templates are split up into separate files that are all @imported into one large file.

Without a framework, Sass puts the cached templates in the .sass-cache directory. In Rails and Merb, they go in tmp/sass-cache. The directory can be customized with the :cache_location option. If you don't want Sass to use caching at all, set the :cache option to false.

Files

SASS_CHANGELOG.md

Latest commit

History

SASS_CHANGELOG.md

File metadata and controls

Sass Changelog

3.0.0.beta.4

Sass Property Syntax

Minor Changes

Bug Fixes

3.0.0.beta.3

@import in Sass

Bug Fixes

3.0.0.beta.2

Stylesheet Updating Speed

New Sass Functions for Introspection

@warn

sass-convert

--recursive

--dasherize

Sass Comment Format

Minor Changes

Bug Fixes

CSS Parsing

Bug Fixes

3.0.0.beta.1

Deprecations -- Must Read!

SCSS (Sassy CSS)

Syntax Changes {#3-0-0-syntax-changes}

SassScript Context

Quoted Strings

Division and /

Variable Defaults

Variable Prefix Character

Variable and Mixin Names

Single-Quoted Strings

Mixin Definition and Inclusion

Colors

Alpha Channels

HSL Colors

Watching for Updates

Bulk Updating

sass-convert (née css2sass) {#3-0-0-sass-convert}

Error Handling

Error Backtraces

Formatting

Ruby 1.9 Support

Rack Support

Firebug Support

Rip Support

Sass::Plugin Callbacks

:compressed Style

Minor Changes

2.2.24 (Unreleased)

2.2.23

2.2.22

2.2.21

2.2.20

2.2.19

2.2.18

2.2.17

Must Read!

2.2.16

2.2.15

2.2.14

SassScript Ruby API

Rack Support

2.2.13

2.2.12

2.2.11

2.2.10

2.2.9

2.2.8

2.2.7

2.2.6

2.2.5

2.2.4

2.2.3

2.2.2

`@import` in Sass

`@warn`

`sass-convert`

`--recursive`

`--dasherize`

Division and `/`

`sass-convert` (née `css2sass`) {#3-0-0-sass-convert}

`:compressed` Style

`:line_comments`

`:template_location`

`@debug` Directive