Semi-continuous Sized Types and Termination

Some type-based approaches to termination use sized types: an ordinal bound for the size of a data structure is stored in its type. A recursive function over a sized type is accepted if it is visible in the type system that recursive calls occur just at a smaller size. This approach is only sound if...

Full description

Bibliographic Details
Main Author: Andreas Abel
Format: Article
Language:English
Published: Logical Methods in Computer Science e.V. 2008-04-01
Series:Logical Methods in Computer Science
Subjects:
Online Access:https://lmcs.episciences.org/1236/pdf
_version_ 1827323045042192384
author Andreas Abel
author_facet Andreas Abel
author_sort Andreas Abel
collection DOAJ
description Some type-based approaches to termination use sized types: an ordinal bound for the size of a data structure is stored in its type. A recursive function over a sized type is accepted if it is visible in the type system that recursive calls occur just at a smaller size. This approach is only sound if the type of the recursive function is admissible, i.e., depends on the size index in a certain way. To explore the space of admissible functions in the presence of higher-kinded data types and impredicative polymorphism, a semantics is developed where sized types are interpreted as functions from ordinals into sets of strongly normalizing terms. It is shown that upper semi-continuity of such functions is a sufficient semantic criterion for admissibility. To provide a syntactical criterion, a calculus for semi-continuous functions is developed.
first_indexed 2024-04-25T01:38:22Z
format Article
id doaj.art-faa27256632d41a6a54282f590c1fefd
institution Directory Open Access Journal
issn 1860-5974
language English
last_indexed 2024-04-25T01:38:22Z
publishDate 2008-04-01
publisher Logical Methods in Computer Science e.V.
record_format Article
series Logical Methods in Computer Science
spelling doaj.art-faa27256632d41a6a54282f590c1fefd2024-03-08T08:51:49ZengLogical Methods in Computer Science e.V.Logical Methods in Computer Science1860-59742008-04-01Volume 4, Issue 210.2168/LMCS-4(2:3)20081236Semi-continuous Sized Types and TerminationAndreas AbelSome type-based approaches to termination use sized types: an ordinal bound for the size of a data structure is stored in its type. A recursive function over a sized type is accepted if it is visible in the type system that recursive calls occur just at a smaller size. This approach is only sound if the type of the recursive function is admissible, i.e., depends on the size index in a certain way. To explore the space of admissible functions in the presence of higher-kinded data types and impredicative polymorphism, a semantics is developed where sized types are interpreted as functions from ordinals into sets of strongly normalizing terms. It is shown that upper semi-continuity of such functions is a sufficient semantic criterion for admissibility. To provide a syntactical criterion, a calculus for semi-continuous functions is developed.https://lmcs.episciences.org/1236/pdfcomputer science - programming languagescomputer science - logic in computer scienced.1.1f.3.2f.4.1
spellingShingle Andreas Abel
Semi-continuous Sized Types and Termination
Logical Methods in Computer Science
computer science - programming languages
computer science - logic in computer science
d.1.1
f.3.2
f.4.1
title Semi-continuous Sized Types and Termination
title_full Semi-continuous Sized Types and Termination
title_fullStr Semi-continuous Sized Types and Termination
title_full_unstemmed Semi-continuous Sized Types and Termination
title_short Semi-continuous Sized Types and Termination
title_sort semi continuous sized types and termination
topic computer science - programming languages
computer science - logic in computer science
d.1.1
f.3.2
f.4.1
url https://lmcs.episciences.org/1236/pdf
work_keys_str_mv AT andreasabel semicontinuoussizedtypesandtermination