Log Message:
devel/hs-dependent-sum: import hs-dependent-sum-0.7.1.0

A dependent sum is a generalization of a particular way of thinking about
the Either type. Either a b can be thought of as a 2-tuple (tag, value),
where the value of the tag determines the type of the value. In particular,
either tag = Left and value :: a or tag = Right and value :: b.

This package allows you to define your own dependent sum types by using
your own "tag" types.