Copyright	(c) Galois Inc 2014-2019
Maintainer	Langston Barrett <[email protected]>
Safe Haskell	Safe
Language	Haskell2010

Data.Parameterized.Compose

Description

Utilities for working with Data.Functor.Compose.

NB: This module contains an orphan instance. It will be included in GHC 8.10, see https://gitlab.haskell.org/ghc/ghc/merge_requests/273 and also https:/github.comhaskell-compatbase-orphansissues/49.

Synopsis

testEqualityComposeBare :: forall k l f (g :: l -> k) (x :: l) (y :: l). (forall (w :: k) (z :: k). f w -> f z -> Maybe (w :~: z)) -> Compose f g x -> Compose f g y -> Maybe (x :~: y)

Documentation

testEqualityComposeBare :: forall k l f (g :: l -> k) (x :: l) (y :: l). (forall (w :: k) (z :: k). f w -> f z -> Maybe (w :~: z)) -> Compose f g x -> Compose f g y -> Maybe (x :~: y) Source #

The deduction (via generativity) that if g x :~: g y then x :~: y.