A practical formalization of monadic equational reasoning in dependent-type theory

Saved in:
Bibliographic Details
Published in:Journal of Functional Programming vol. 35 (Jan 2025)
Main Author: Affeldt, Reynald
Other Authors: Garrigue, Jacques, Saikawa, Takafumi
Published:
Cambridge University Press
Subjects:
Online Access:Citation/Abstract
Full Text - PDF
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Abstract:One can perform equational reasoning about computational effects with a purely functional programming language thanks to monads. Even though equational reasoning for effectful programs is desirable, it is not yet mainstream. This is partly because it is difficult to maintain pencil-and-paper proofs of large examples. We propose a formalization of a hierarchy of effects using monads in the Coq proof assistant that makes monadic equational reasoning practical. Our main idea is to formalize the hierarchy of effects and algebraic laws as interfaces like it is done when formalizing hierarchy of algebras in dependent-type theory. Thanks to this approach, we clearly separate equational laws from models. We can then take advantage of the sophisticated rewriting capabilities of Coq and build libraries of lemmas to achieve concise proofs of programs. We can also use the resulting framework to leverage on Coq’s mathematical theories and formalize models of monads. In this article, we explain how we formalize a rich hierarchy of effects (nondeterminism, state, probability, etc.), how we mechanize examples of monadic equational reasoning from the literature, and how we apply our framework to the design of equational laws for a subset of ML with references.
ISSN:0956-7968
1469-7653
DOI:10.1017/S0956796824000157
Source:Advanced Technologies & Aerospace Database