Monads need not be endofunctors

We introduce a generalization of monads, called relative monads, allowing for underlying functors between different categories. Examples include finite-dimensional vector spaces, untyped and typed λ-calculus syntax and indexed containers. We show that the Kleisli and Eilenberg-Moore constructions ca...

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Main Authors: Altenkirch, Thorsten, Chapman, James, Uustalu, Tarmo
Format: Article
Published: International federation of Computer Logic 2015
Subjects:
Online Access:https://eprints.nottingham.ac.uk/30436/
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author Altenkirch, Thorsten
Chapman, James
Uustalu, Tarmo
author_facet Altenkirch, Thorsten
Chapman, James
Uustalu, Tarmo
author_sort Altenkirch, Thorsten
building Nottingham Research Data Repository
collection Online Access
description We introduce a generalization of monads, called relative monads, allowing for underlying functors between different categories. Examples include finite-dimensional vector spaces, untyped and typed λ-calculus syntax and indexed containers. We show that the Kleisli and Eilenberg-Moore constructions carry over to relative monads and are related to relative adjunctions. Under reasonable assumptions, relative monads are monoids in the functor category concerned and extend to monads, giving rise to a coreflection between relative monads and monads. Arrows are also an instance of relative monads.
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spelling nottingham-304362020-05-04T17:04:57Z https://eprints.nottingham.ac.uk/30436/ Monads need not be endofunctors Altenkirch, Thorsten Chapman, James Uustalu, Tarmo We introduce a generalization of monads, called relative monads, allowing for underlying functors between different categories. Examples include finite-dimensional vector spaces, untyped and typed λ-calculus syntax and indexed containers. We show that the Kleisli and Eilenberg-Moore constructions carry over to relative monads and are related to relative adjunctions. Under reasonable assumptions, relative monads are monoids in the functor category concerned and extend to monads, giving rise to a coreflection between relative monads and monads. Arrows are also an instance of relative monads. International federation of Computer Logic 2015-03-06 Article PeerReviewed Altenkirch, Thorsten, Chapman, James and Uustalu, Tarmo (2015) Monads need not be endofunctors. Logical Methods in Computer Science, 11 (1:3). pp. 1-40. ISSN 1860-5974 monads adjunctions monoids skew-monoidal categories functional programming http://www.www.lmcs-online.org/ojs/viewarticle.php?id=946&layout=abstract doi:10.2168/LMCS-11(1:3)2015 doi:10.2168/LMCS-11(1:3)2015
spellingShingle monads
adjunctions
monoids
skew-monoidal categories
functional programming
Altenkirch, Thorsten
Chapman, James
Uustalu, Tarmo
Monads need not be endofunctors
title Monads need not be endofunctors
title_full Monads need not be endofunctors
title_fullStr Monads need not be endofunctors
title_full_unstemmed Monads need not be endofunctors
title_short Monads need not be endofunctors
title_sort monads need not be endofunctors
topic monads
adjunctions
monoids
skew-monoidal categories
functional programming
url https://eprints.nottingham.ac.uk/30436/
https://eprints.nottingham.ac.uk/30436/
https://eprints.nottingham.ac.uk/30436/