This paper defines a new concurrent logic language, Nested Guarded Horn Clauses (NGHC). The main new feature of the language is its concept of guard. In fact, an NGHC clause has several layers of (standard) guards. This syntactic innovation allows the definition of a complete (i.e. always applicable) set of unfolding rules and therefore of an unfolding semantics which is equivalent, with respect to the success set, to the operational semantics. A fixpoint semantics is also defined in the classic logic programming style and is proved equivalent to the unfolding one. Since it is possible to embed Flat GHC into NGHC, our method can be used to give a fixpoint semantics to FGHC as well.

Falaschi, M., Gabbrielli, M., Levi, G., Murakami, M. (1990). Nested Guarded Horn Clauses. INTERNATIONAL JOURNAL OF FOUNDATIONS OF COMPUTER SCIENCE, 1(3), 249-263 [10.1142/S0129054190000187].

Nested Guarded Horn Clauses

FALASCHI, MORENO;
1990-01-01

Abstract

This paper defines a new concurrent logic language, Nested Guarded Horn Clauses (NGHC). The main new feature of the language is its concept of guard. In fact, an NGHC clause has several layers of (standard) guards. This syntactic innovation allows the definition of a complete (i.e. always applicable) set of unfolding rules and therefore of an unfolding semantics which is equivalent, with respect to the success set, to the operational semantics. A fixpoint semantics is also defined in the classic logic programming style and is proved equivalent to the unfolding one. Since it is possible to embed Flat GHC into NGHC, our method can be used to give a fixpoint semantics to FGHC as well.
1990
Falaschi, M., Gabbrielli, M., Levi, G., Murakami, M. (1990). Nested Guarded Horn Clauses. INTERNATIONAL JOURNAL OF FOUNDATIONS OF COMPUTER SCIENCE, 1(3), 249-263 [10.1142/S0129054190000187].
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11365/36094
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo