base-orphans defines orphan instances that mimic instances available in
later versions of base to a wider (older) range of compilers.
base-orphans does not export anything except the orphan instances
themselves and complements <http://hackage.haskell.org/package/base-compat
base-compat>.
See the README for what instances are covered:
https://github.com/haskell-compat/base-orphans#readme.
See also the
what is not covered
section.