Recursion parameterised by Monads: Examples and characterisation

Johan Glimming

(Stockholm University visiting University of Nottingham)

Fokkinga (1994) constructed an adjunction between the category of F-algebras and the category of lifted F-algebras for monads M given a certain natural transformation dist_F, and regular F. The left adjoint in the construction (with its preservation of colimits) allow translation of recursion schemas to schemas parameterised by monads. In this talk I will explain Fokkinga's construction and give concrete examples of its use in functional programming, e.g. the relationship between recursion and stateful objects represented by state monads. I further discuss shortcomings with Fokkinga's monadic lifting, and describe my current work on generalising the lifting construction.
Tuesday 9th December 2003, 14:00
Robert Recorde Room
Department of Computer Science