Abstract
We present a new semantics for a language in the family of concurrent constraint logic languages. The semantics can be based on a notion of clause unfolding, since the language is closed under this transformation. The unfolding semantics is obtained as limit of an infinite unfolding process. Unfolding is also used to define an immediate consequences operator, and, therefore, a fixpoint semantics in the typical logic programming style. The result of both the unfolding and the fixpoint semantics is a set of reactive behaviors, which are trees abstractly representing all the possible computations of a program, including deadlocks and finite failures. The semantics can be made more abstract by defining a suitable notion of equivalence on reactive behaviors. In our approach this can be done by reasoning on constraints only, thus generalizing the typical behavior of constraint logic programming.
Part of this work is supported by the ESPRIT Basic Research Action P3020 “Integration” and by SELENIA S.p.a.
Preview
Unable to display preview. Download preview PDF.
References
L. Beckman. Towards a formal semantics for concurrent logic programming languages. In E. Shapiro, editor, Proc. Third ICLP, volume 225 of LNCS, pages 335–349. Springer-Verlag, 1986.
R. M. Burstall and J. Darlington. A transformation system for developing recursive programs. JACM, 24(1), 1977.
K.L. Clark and S. Gregory. PARLOG: parallel programming in logic. ACM Trans. on Programming Languages and Systems, 8:1–49, 1986.
P.L. Courien. Categorical combinators, sequential algorithms and functional programming. In Research Notes in Theoretical Computer Science. Pitman, 1986.
J.W. de Bakker and J.N. Kok. Uniform abstraction, atomicity and contractions in the comparative semantics of Concurrent Prolog. In Proc. Int'l Conf. FGCS, pages 347–355, Tokyo, Japan, 1988. ICOT.
F.S. de Boer, J.N. Kok, C. Palamidessi, and J.J.M.M. Rutten. Control flow versus logic: a denotational and a declarative model for Guarded Horn Clauses. In A. Kreczmar and G. Mirkowska, editors, Proc. Symp. on Mathematical Foundations of Computer Science, volume 379 of LNCS, pages 165–176. Springer-Verlag, 1989.
F.S. de Boer, J.N. Kok, C. Palamidessi, and J.J.M.M. Rutten. Semantic models for a version of PARLOG. In G. Levi and M. Martelli, editors, Proc. Sixth ICLP, Series in Logic Programming, pages 621–636, Lisboa, 1989. The MIT Press. Extended version to appear in Theoretical Computer Science.
F.S. de Boer and C. Palamidessi. Concurrent logic languages: Asynchronism and language comparison. In Proc. NACLP'90. The MIT Press, 1990.
F.S. de Boer and C. Palamidessi. On the asynchronous nature of communication in concurrent logic languages: A fully abstract model based on sequences. In Proc. of Concur 90, The Netherlands, 1990.
M. Falaschi, M. Gabbrielli, G. Levi, and M. Murakami. Nested Guarded Horn Clauses: a language provided with a complete set of Unfolding Rules. In Proc. Japanese Nat'l Conf. on Logic Programming '89, 1989.
M. Falaschi, G. Levi, M. Martelli, and C. Palamidessi. A new declarative semantics for logic languages. In R. A. Kowalski and K. A. Bowen, editors, Proc. Fifth ICLP, pages 993–1005. The MIT Press, 1988.
M. Falaschi, G. Levi, M. Martelli, and C. Palamidessi. Declarative modeling of the operational behavior of logic languages. TCS, 69(3):289–318, 1989.
M. Falaschi, G. Levi, M. Martelli, and C. Palamidessi. A model-theoretic reconstruction of the operational semantics of logic programs. Technical Report TR 3/89, Dip. Informatica, Univ. di Pisa, Pisa, 1989.
H. Fujita, A. Okumura, and K. Furukawa. Partial evaluation of GHC programs based on the UR-Set with constraints. In R. A. Kowalski and K. A. Bowen, editors, Proc. Fifth ICLP, pages 924–941. The MIT Press, 1988.
K. Furukawa, A. Okumura, and M. Murakami. Unfolding rules for GHC programs. New Generation Computing, 6:143–158, 1988.
M. Gabbrielli and G. Levi. An unfolding reactive semantics for concurrent constraint programming. Technical report, Dip. di Informatica, Univ. di Pisa, Pisa, 1990.
H. Gaifman, M. J. Maher, and E. Shapiro. Reactive Behaviour semantics for Concurrent Constraint Logic Programs. In E. Lusk and R. Overbeck, editors, Proc. NACLP'89, 1989.
R. Gerth, M. Codish, Y. Lichtenstein, and E. Shapiro. Fully abstract denotational semantics for Concurrent Prolog. In Proc. third LICS, pages 320–335. IEEE Computer Society Press, 1988.
H.Tamaki and T. Sato. Unfold/Fold Transformations of Logic Programs. In Sten-Åke Tarnlund, editor, Proc. Second ICLP, pages 127–139, 1984.
J. Jaffar and J.-L. Lassez. Constraint Logic Programming. In Proc. fourteenth POPL, pages 111–119. ACM, 1987.
J. L. Lassez, M. J. Maher, and K. Marriott. Unification Revisited. In J. Minker, editor, Foundations of Deductive Databases and Logic Programming. Morgann Kaufmann, 1988.
G. Levi. Models, Unfolding Rules and Fixpoint Semantics. In R. A. Kowalski and K. A. Bowen, editors, Proc. Fifth ICLP, pages 1649–1665. The MIT Press, 1988.
G. Levi and P. Mancarella. The unfolding semantics of logic programs. Technical Report TR-13/38, Dip. di Informatica, Univ. di Pisa, 1988.
G. Levi and C. Palamidessi. The declarative semantics of logical read-only variables. In Proc. IEEE Symp. on Logic Programming, pages 128–137. IEEE Computer Society Press, 1985.
G. Levi and C. Palamidessi. An approach to the declarative semantics of synchronization in logic languages. In J.-L. Lassez, editor, Proc. Fourth ICLP, pages 877–893. The MIT Press, 1987.
M. J. Maher. Logic semantics for a class of committed-choice programs. In J.-L. Lassez, editor, Proc. Fourth ICLP, pages 858–876. The MIT Press, 1987.
R. Milner. Lectures on a calculus for communicating systems. In S. Brookes, A. Roscoe, and G. Winskell, editors, Seminar on Concurrency, volume 197 of LNCS. Springer-Verlag, 1984.
M. Murakami. A declarative semantics of parallel logic programs with perpetual processes. In Proc. Int'l Conf. FGCS, pages 374–381. ICOT, 1988.
V. A. Saraswat. A somewhat logical formulation of CLP synchronization primitives. In R. A. Kowalski and K. A. Bowen, editors, Proc. Fifth ICLP, pages 1298–1314. The MIT Press, 1988.
V.A. Saraswat. GHC: operational semantics, problems and relationship with CP(↓,|). In IEEE Int'l Symp. on Logic Programming, pages 347–358. IEEE, 1987.
V.A. Saraswat. Concurrent Constraint Programming Languages. PhD thesis, Carnegie-Mellon University, January 1989.
V.A. Saraswat and M. Rinard. Concurrent constraint programming. In Proc. seventeenth POPL. ACM, 1990.
E. Y. Shapiro. Concurrent Prolog: A progress report. Computer, 19(8):44–58, 1986.
K. Ueda. Guarded Horn Clauses. In E. Y. Shapiro, editor, Concurrent Prolog: Collected Papers. The MIT Press, 1987.
K. Ueda and K. Furukawa. Transformation rules for GHC Programs. In Proc. Int'l Conf. FGCS, pages 582–591. ICOT, 1988.
M.H. van Emden and R.A. Kowalski. The semantics of predicate logic as a programming language. JACM, 23(4):733–742, 1976.
Author information
Authors and Affiliations
Editor information
Rights and permissions
Copyright information
© 1990 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Gabbrielli, M., Levi, G. (1990). Unfolding and fixpoint semantics of concurrent constraint logic programs. In: Kirchner, H., Wechler, W. (eds) Algebraic and Logic Programming. ALP 1990. Lecture Notes in Computer Science, vol 463. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-53162-9_40
Download citation
DOI: https://doi.org/10.1007/3-540-53162-9_40
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-53162-3
Online ISBN: 978-3-540-46738-0
eBook Packages: Springer Book Archive