| Copyright | 2008 Edward Kmett |
|---|---|
| License | BSD |
| Maintainer | Edward Kmett <ekmett@gmail.com> |
| Stability | experimental |
| Portability | portable |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
Control.Category.Associative
Description
NB: this contradicts another common meaning for an Associative Category, which is one
where the pentagonal condition does not hold, but for which there is an identity.
- class Bifunctor p k k k => Associative k p where
- associate :: k (p (p a b) c) (p a (p b c))
- disassociate :: k (p a (p b c)) (p (p a b) c)
Documentation
class Bifunctor p k k k => Associative k p where Source
A category with an associative bifunctor satisfying Mac Lane's pentagonal coherence identity law:
bimap id associate . associate . bimap associate id = associate . associate bimap disassociate id . disassociate . bimap id disassociate = disassociate . disassociate
Methods
associate :: k (p (p a b) c) (p a (p b c)) Source
disassociate :: k (p a (p b c)) (p (p a b) c) Source
Instances
| Associative (->) Either | |
| Associative (->) (,) |