The power of non-determinism in higher-order implicit complexity: characterising complexity classes using non-deterministic cons-free programming

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We investigate the power of non-determinism in purely functional programming languages with higher-order types. Specifically, we consider cons-free programs of varying data orders, equipped with explicit non-deterministic choice. Cons-freeness roughly means that data constructors cannot occur in function bodies and all manipulation of storage space thus has to happen indirectly using the call stack. While cons-free programs have previously been used by several authors to characterise complexity classes, the work on non-deterministic programs has almost exclusively considered programs of data order 0. Previous work has shown that adding explicit non-determinism to consfree programs taking data of order 0 does not increase expressivity; we prove that this—dramatically—is not the case for higher data orders: adding non-determinism to programs with data order at least 1 allows for a characterisation of the entire class of elementary-time decidable sets. Finally we show how, even with non-deterministic choice, the original hierarchy of characterisations is restored by imposing different restrictions.

Original languageEnglish
Title of host publicationProgramming Languages and Systems : 26th European Symposium on Programming, ESOP 2017, Held as Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2017, Uppsala, Sweden, April 22–29, 2017, Proceedings
EditorsHongseok Yang
Number of pages28
PublisherSpringer
Publication date2017
Pages668-695
ISBN (Print)978-3-662-54433-4
ISBN (Electronic)978-3-662-54434-1
DOIs
Publication statusPublished - 2017
Event26th European Symposium on Programming - Uppsala, Sweden
Duration: 22 Apr 201729 Apr 2017
Conference number: 26

Conference

Conference26th European Symposium on Programming
Nummer26
LandSweden
ByUppsala
Periode22/04/201729/04/2017
SeriesLecture notes in computer science
Volume10201
ISSN0302-9743

    Research areas

  • Cons-free programming, EXPTIME hierarchy, Implicit computational complexity, Non-deterministic programming, Unitary variables

Links

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