Module

Control.Category

Package
purescript-prelude
Repository
purescript/purescript-prelude

#Category Source

class (Semigroupoid a) <= Category a  where

Categorys consist of objects and composable morphisms between them, and as such are Semigroupoids, but unlike semigroupoids must have an identity element.

Instances must satisfy the following law in addition to the Semigroupoid law:

  • Identity: identity <<< p = p <<< identity = p

Members

Instances

Re-exports from Control.Semigroupoid

#Semigroupoid Source

class Semigroupoid a  where

A Semigroupoid is similar to a Category but does not require an identity element identity, just composable morphisms.

Semigroupoids must satisfy the following law:

  • Associativity: p <<< (q <<< r) = (p <<< q) <<< r

One example of a Semigroupoid is the function type constructor (->), with (<<<) defined as function composition.

Members

  • compose :: forall b c d. a c d -> a b c -> a b d

Instances

#(>>>) Source

Operator alias for Control.Semigroupoid.composeFlipped (right-associative / precedence 9)

#(<<<) Source

Operator alias for Control.Semigroupoid.compose (right-associative / precedence 9)