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arXiv · 1503.02447

Presenting Distributive Laws

Marcello M. Bonsangue·Helle Hvid Hansen·Alexander Kurz·Jurriaan Rot
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Abstract

Distributive laws of a monad T over a functor F are categorical tools for specifying algebra-coalgebra interaction. They proved to be important for solving systems of corecursive equations, for the specification of well-behaved structural operational semantics and, more recently, also for enhancements of the bisimulation proof method. If T is a free monad, then such distributive laws correspond to simple natural transformations. However, when T is not free it can be rather difficult to prove the defining axioms of a distributive law. In this paper we describe how to obtain a distributive law for a monad with an equational presentation from a distributive law for the underlying free monad. We apply this result to show the equivalence between two different representations of context-free languages.

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Marcello M. Bonsangue, Helle Hvid Hansen, Alexander Kurz, Jurriaan Rot. 2015-03-09. Presenting Distributive Laws. https://doi.org/10.2168/lmcs-11(3:2)2015

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