I'm pretty sure its not.I'm pretty sure that is JavaScript, my friend.
I've seen it outside of Rev, and it is the same way in JavaScript based sites.I'm pretty sure its not.
To awnser your question, I guess you are getting this idea from RevCMS. They use a template system for it, so unless you have one, you can't do it that way.
Maybe they made a template system... but {} has nothing to do with setting {url} to localhost or w/e.I've seen it outside of Rev, and it is the same way in JavaScript based sites.