Skip to main content

Denotational semantics of recursive types in synthetic guarded domain theory

Møgelberg, Rasmus, Paviotti, Marco (2016) Denotational semantics of recursive types in synthetic guarded domain theory. In: Proceedings of the 31st Annual ACM/IEEE Symposium on Logic in Computer Science. LICS Logic in Computer Science . pp. 317-326. ACM, New York, USA ISBN 978-1-4503-4391-6. (doi:10.1145/2933575.2934516) (KAR id:65016)


Guarded recursion is a form of recursion where recursive calls are guarded by delay modalities. Previous work has shown how guarded recursion is useful for reasoning operationally about programming languages with advanced features including general references, recursive types, countable non-determinism and concurrency.

Guarded recursion also offers a way of adding recursion to type theory while maintaining logical consistency. In previous work we initiated a programme of denotational semantics in type theory using guarded recursion, by constructing a computationally adequate model of the language PCF (simply typed lambda calculus with fixed points). This model was intensional in that it could distinguish between computations computing the same result using a different number of fixed point unfoldings.

In this work we show how also programming languages with recursive types can be given denotational semantics in type theory with guarded recursion. More precisely, we give a computationally adequate denotational semantics to the language FPC (simply typed lambda calculus extended with recursive types), modelling recursive types using guarded recursive types. The model is intensional in the same way as was the case in previous work, but we show how to recover extensionality using a logical relation.

All constructions and reasoning in this paper, including proofs of theorems such as soundness and adequacy, are by (informal) reasoning in type theory, often using guarded recursion.

Item Type: Conference or workshop item (Paper)
DOI/Identification number: 10.1145/2933575.2934516
Uncontrolled keywords: Recursive Types, Type Theory, Denotational semantics, Category Theory, Domain Theory
Subjects: Q Science > QA Mathematics (inc Computing science)
Divisions: Divisions > Division of Computing, Engineering and Mathematical Sciences > School of Computing
Depositing User: Marco Paviotti
Date Deposited: 05 Dec 2017 15:17 UTC
Last Modified: 16 Mar 2023 23:21 UTC
Resource URI: (The current URI for this page, for reference purposes)

University of Kent Author Information

  • Depositors only (login required):

Total unique views for this document in KAR since July 2020. For more details click on the image.