libghc-these-dev - 1.2.1-1 main

Package provides a data type `These a b' which can hold a value of either
type or values of each type. This is usually thought of as an "inclusive or"
type (contrasting `Either a b' as "exclusive or") or as an "outer join" type
(contrasting `(a, b)' as "inner join").
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The major use case of this is provided by the Align class, representing a
generalized notion of "zipping with padding" that combines structures without
truncating to the size of the smaller input.
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Also included is ChronicleT, a monad transformer based on the Monad instance
for `These a', along with the usual monad transformer bells and whistles.
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This package provides a library for the Haskell programming language.
See http://www.haskell.org/ for more information on Haskell.