Data.Semigroupoid.Dual

semigroupoids-1.2.6: Haskell 98 semigroupoids: Category sans id

Portability | portable
Stability | provisional
Maintainer | Edward Kmett <ekmett@gmail.com>

Data.Semigroupoid.Dual

Description

A semigroupoid satisfies all of the requirements to be a Category except for the existence of identity arrows.

# Documentation

newtype Dual k a b

Constructors

Dual |
Fields getDual :: k b a

Instances

Category k => Category (Dual k) |
Semigroupoid k => Semigroupoid (Dual k) |