meiersi/strict-base-types — pull request #2 by Taneb (2013-05-10 15:08:08+00:00)
Title: Lots additions

* Bifunctor, Bifoldable and Bitraversable instances for Pair and Either
* Field1, Field2, Swapped and Each instances for Pair
* new function "swap" in .Tuple
* Swapped instance for Either
* _Left, _Right, _Just, and _Nothing prisms