Since profile IUSE_IMPLICIT settings may diverge from those
that a binary package was built with, consider members of
built USE settings to be members of IUSE_EFFECTIVE. Only do
this for EAPIs that support IUSE_EFFECTIVE, since built USE
settings for earlier EAPIs may contain a large number of
Unfortunately I am way too busy to even entertain looking into this in
any detail. A few years ago I was hoping to work on something like this,
though in Agda (or possibly in Haskell or Coq), and do work on making
Portage much more modular so that you could actually pick whatever
dependency
