Abstract
Unlike most other logic programming languages. Concurrent Prolog5) does not include a sequential-AND operator to enforce serial goal (process) reduction. However, sequential process reduction is still possible using existing constructs. In a number of published programming examples it is achieved with the “commit” operator. Such programs may not execute as described, but instead encounter deadlock. In this paper several examples of this are presented, the cause of the problem is diagnosed, and a solution suggested.
This paper also deals with sequential process reduction in more general terms. The methods available to achieve serialization involving commit and read-only variable references are analyzed and compared. The potential for incorporating sequential-AND into the language is also addressed.
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Kusalik, A.J. Serialization of process reduction in Concurrent Prolog. NGCO 2, 289–298 (1984). https://doi.org/10.1007/BF03037062
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DOI: https://doi.org/10.1007/BF03037062