Quick note: at the suggestion of Aman Gupta, PackR now supports
Packr.pack, Packr.minify and Packr.pack_file as class methods, so you
don’t need to create an instance of PackR before doing anything. Originally, I
wanted PackR’s design to mirror the JavaScript version to make maintainance
easier, but these methods are a tiny addition so I’m happy to put them in.
PackR, now with class methods
