Portability | GADTs, TFs, MPTCs |
---|---|

Stability | provisional |

Maintainer | Edward Kmett <ekmett@gmail.com> |

Safe Haskell | Trustworthy |

- newtype Yoneda f a = Yoneda {
- runYoneda :: forall r. (r -> a) -> f r

- liftYoneda :: Contravariant f => f a -> Yoneda f a
- lowerYoneda :: Yoneda f a -> f a

# Documentation

Yoneda embedding for a presheaf

Contravariant (Yoneda f) | |

Valued f => Valued (Yoneda f) | |

Coindexed f => Coindexed (Yoneda f) | |

Representable f => Representable (Yoneda f) | |

Adjunction f g => Adjunction (Yoneda f) (Yoneda g) |

liftYoneda :: Contravariant f => f a -> Yoneda f aSource

`liftYoneda`

.`lowerYoneda`

≡`id`

`lowerYoneda`

.`liftYoneda`

≡`id`

lowerYoneda :: Yoneda f a -> f aSource