These aren't functions in the traditional programming sense. Looking at examples in the spec, they're mostly a way to do conditional logic around which properti

These aren't functions in the traditional programming sense. Looking at examples in the spec, they're mostly a way to do conditional logic around which properties to apply when (desperately needed in CSS as the only way to do this now—if at all—is with media queries, funky selectors, or as a last resort, JavaScript). Just finished work on a new CSS framework and would have loved to have stuff like this. If it lands with baseline support, I'd be able to save a lot of footprint using these.