On Wednesday, 20 May 2015 at 18:55:11 UTC, Jacob Carlborg wrote:
libarchive supports it, which has a BSD license. Yeah, I know that we most likely cannot use it.
If RAR support is to be had, interfacing with libarchive is probably going to be the best/easiest way to do it, although it would probably be better to focus on adding support for those archives that don't need an extra library first.