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arXiv · 0903.2205

A Lightweight Combination of Semantics for Non-deterministic Functions

Francisco Javier Lopez-Fraguas·Juan Rodriguez-Hortala·Jaime Sanchez-Hernandez
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Abstract

The use of non-deterministic functions is a distinctive feature of modern functional logic languages. The semantics commonly adopted is call-time choice, a notion that at the operational level is related to the sharing mechanism of lazy evaluation in functional languages. However, there are situations where run-time choice, closer to ordinary rewriting, is more appropriate. In this paper we propose an extension of existing call-time choice based languages, to provide support for run-time choice in localized parts of a program. The extension is remarkably simple at three relevant levels: syntax, formal operational calculi and implementation, which is based on the system Toy.

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Francisco Javier Lopez-Fraguas, Juan Rodriguez-Hortala, Jaime Sanchez-Hernandez. 2009-03-12. A Lightweight Combination of Semantics for Non-deterministic Functions. https://arxiv.org/abs/0903.2205

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