LESS is a language which extends
CSS with dynamic behavior such as variables, mixins, operations
and functions. This plugin extends the Eclipse IDE by providing
handy features to edit and compile LESS stylesheets.
Syntax is automatically colored in the LESS editor as you type.
The outline view provides an overview of your style sheet,
and an easy access to its components.
Press CTRL+space to get a context
relevant list of completion proposals for CSS properties and
Errors and warnings
Potential errors in your stylesheet are detected in
background and signaled by problem markers.
Variable and Mixin linking
Variable and mixin uses are automatically linked to their
definition, allowing navigation and detection of undefined
Launch the LESS compiler
Create launch configurations for LESS stylesheets, and run
them directly from their contextual menu.
Jump to the next error and fix it
The error messages of the LESS compiler are directly
provided in the Eclipse IDE, with hyperlinks to the source
The Eclipse LESS plugin should run on all platforms where
Eclipse and LESS are supported.
Step 1: Install Base Software
In order to use the Eclipse LESS plugin, you need:
- Eclipse Kepler (version 4.3 or later). You can download
it from the
- The LESS compiler (if you want to compile your stylesheets in CSS),
version 1.5 or further. You can download it
Step 2: Install the plugin
- Open again the update manager (menu Help, then Install
- In the field Work with:, enter the URL of the update
- Select the LESS plugin.
- Click on Next and validate the following messages to finalize
- During the installation, Eclipe will show a security
warning. You need to acknowledge it.
- At the end of the installation, Eclipse proposes you to
restart Eclipse for the installation to take effect. You
should accept by clicking on Restart Now.
Note: When installing the plugin, the Eclipse
installation tool will automatically install required plugins
from Eclipse repository (including Xtext).
How to use it?
Once you have installed the plugin, you just need to create a
file with the file extension
.less in any project.
This file will automatically be opened with the LESS editor.
You may register additional file extensions for LESS
stylesheets in the Eclipse Preferences (menu Window,
then Preferences...), section General > Content
You can disable some errors/warnings on a per-project warning,
by editing the project properties (tab Validation > LESS.
In order to launch the LESS compiler from Eclipse, you need to
create a launch configuration. For this:
- In the menu Run, select Run
- Select LESS Compiler in the list on the left hand
side of the dialog, then click on the icon to create a new
launch configuration at the top of this list,
- Configure the options to run the LESS compiler (in
particular the LESS command if
lessc is not in
your system path) and check the option Use this launch
configuration as default.
Once this is done, you may compile any LESS stylesheet by
selecting it in the project explorer, clicking on the right
button to open the contextual menu and selecting Run
as, LESS Compiler. This will use the default launch
configuration you just created. You can also create specific
launch configurations for each of your stylesheet.
The Eclipse LESS plugin is distributed under the
Plublic License Version 1.0.
It includes some files from
the Eclipse Webtools
Project. These files are also distributed under the Eclipse
Public License Version 1.0.
- Version 1.0.22 (2014-11-01):
Compatibility with Xtext 2.7.
- Version 1.0.21 (2014-06-01):
Support of new import options.
Fix parsing of
- Version 1.0.20 (2014-05-25):
Auto-edits (like insertion of quotes) can now be disabled
Fix bug in mixin validation.
Numeric values in attribute selectors.
Fix bug leading to comments appearing in outline.
Support variables in property names.
Fix bug with dashes in selector names.
- Version 1.0.19 (2014-01-26): LESS 1.5.0 support
support property merging (
support guards on simple selectors.
support variables in
fix bug with unspecified mixin parameter.
fix bug with dummy separator in mixin parameters.
- Version 1.0.18 (2013-08-31):
Improving content-assist for mixins.
Fix parsing of selector with
Parsing of variables in pseudo-selectors.
Allowing mixin calls in
Fixing scope of variables in parameter values.
Allowing variables in
Enabling different colors for different types of selectors.
Fix import of files without the
extension as LESS stylesheets.
- Version 1.0.17 (2013-06-02):
@import statements with specified format.
Proper handling of
Better handling of multiple mixin definitions.
- Version 1.0.16 (2013-04-11):
Move project property page under Validation.
Allow disabling of error messages for undefined variables
- Version 1.0.15 (2013-04-01):
Support for named parameters in mixin calls. This version
also includes fixes for
detected on the beta-version.
Support semicolons as separator between mixin parameters.
Fix various errors in parsing of LESSHat file.
- Version 1.0.14 (2013-03-10):
Make some warnings and errors configurable through project
!important) on mixin calls.
@import statements with a file extension
Anomymous collector mixin parameters.
Variables in media queries.
< in mixin guards.
Fixing bug in parisong of some pseudo-class arguments.
Variables as pseudo-class arguments.
- Version 1.0.13 (2013-01-01):
New dimension units.
@import-once and @import-multiple.
Variable length arguments in mixins.
Variables in selectors.
Top-level mixin calls.
- Version 1.0.12 (2012-10-27):
Ignore import statements with non-file URIs.
- Version 1.0.11 (2012-10-14):
Support nested @media, @page, @font-face and @charset
Change of syntax coloring preferences does no longer
require restarting Eclipse.
- Version 1.0.10 (2012-08-11):
- Compatibility with Eclipse 4.
- Version 1.0.9 (2012-06-16):
Syntax coloring for numeric literals (disabled by default,
can be enabled in editor's preferences).
- Version 1.0.7 (2012-05-28):
Escape sequences in identifiers.
Escape sequences in strings.
- Version 1.0.6 (2012-05-19):
Make launch configurations suitable for
Fix null pointer exception when browsing a file with unknown
content-type in the launch configuration.
Better syntax coloring of mixin declarations, mixin calls
and variable uses.
Fix error messages for undefined mixins.
Allow comma-separated terms in variable definitions.
- Supporting new command-line options of the LESS
- Version 1.0.5 (2012-05-04):
First version of the code formatter.
Distinguishing CSS from LESS stylesheets in import statements.
Parsing of the special variable @arguments.
- Implementing some new features from the LESS language
- Version 1.0.4 (2012-04-22):
correct parsing of mixin parameters with several terms.
- Version 1.0.3 (2012-04-11):
Compatibility issue with Java 5.
- Version 1.0.2 (2012-04-04):
- CSS3 selectors and media queries,
- Cross-references between files.
- Version 1.0.1 (2012-03-08):
better handling of
& in selectors.
handling of the star-property-hack.
- Version 1.0.0: First release.
The following constructs of the LESS language are not (yet)
- CSS escapes (css-escapes.less)
- Empty property values (css.less)
- Special case of the font: property
- Mixin matching based on number of arguments
The following features are not supported in the editor: