After I watched this NetTUTs video, I\'m very interested in trying out the LESS.js method shown.
Other than the obvious, \"What if the user doesn\'t have javascript
I can't see any reason why it should be used in production. It makes more sense to run this as a build script, then make the output (regular CSS) available on a cached cookie-free domain. Then, it works fine without JavaScript and doesn't require JavaScript processing (which will be slower than the CSS parsers written in tuned native code) on every page load.
I haven't tried in production, but there may be some interesting use cases around LESS variables. For example, you could change underlying less variables that in turn change a bunch of dependent CSS rules (relative widths/heights for example).
See https://stackoverflow.com/a/8742705/255961 for interesting patch that makes it very easy to change them using a simple modifyVars()
function.
With it you could change your Bootstrap grid size and everything that depends on it with a single, local JS call:
less.modifyVars({
'@gridColumnWidth': 50px
});
Yes, if people with Javascript disabled is a concern, then I would recommend against the Javascript-based LESS. Personally, I see no advantage in it over the Ruby-based one, since you really only need Ruby installed on your development machine - once you compile the .less file to a .css, there's no difference between a LESS-compiled .css file and "hand-written" one.