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arXiv · 2407.05715

The Size-Change Principle for Mixed Inductive and Coinductive types

Pierre Hyvernat
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Abstract

This paper shows how to use Lee, Jones and Ben Amram's size-change principle to check correctness of arbitrary recursive definitions in an ML / Haskell like programming language with inductive and coinductive types. Naively using the size-change principle to check productivity and termination is straightforward but unsound when inductive and coinductive types are nested. We can however adapt the size-change principle to check ``totality'', which corresponds exactly to correctness with respect to the corresponding (co)inductive type.

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Pierre Hyvernat. 2024-07-08. The Size-Change Principle for Mixed Inductive and Coinductive types. https://doi.org/10.46298/lmcs-21(3%3A20)2025

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