The @warn directive

Sass also has a @warn directive that enjoys similar functionality to @debug. For example:

@warn $theme-tint;

Unlike @debug, messages generated by @warn can be universally suppressed by adding the following to Compass's config.rb file:

sass_options = {:quiet => true}

To re-enable warnings, either comment out the line or amend it like so:

sass_options = {:quiet => false}