Undeclared mixin error when using semicolon in multiple parameter Less file

less, twitter-bootstrap, web-essentials

Solution

Unfortunately, the Web Essentials plugin for Visual Studio has not been keeping up with all of the LESS CSS standards and fails when semicolons are used as separators. In the meantime, you'll want to convert the semicolons to commas, with the downside that you'll no long be able to pass a list of arguments.

Web Essentials is constantly being updated, so I wouldn't be surprised if this is fixed very soon.

Problem

I am trying to use the mixins.less file from Twitter Bootstrap in my project. All instances of multiple parameters that are separated by semi-colons show: Undeclared mixin The function arguments are unclosed, ')' expected. Undeclared variable I have WebEssentials 2012 v2.9 installed. Is there a way to get this working without using a different Less compiler? Or is the compiler in WebEssentials not the issue?

Original source