From Failure to Success: Comparing a Denotational and a Declarative Semantics forHorn Clause Logic

摘要

The most basic example of a (parallel) logic programming language is Horn ClauseLogic (HCL). A study aimed at relating different models for HCL, operational, denotational, declarative, is presented. Their relationship is studied by contrasting models based on interleaving, on the one hand, to models based on maximal parallelism, on the other. Complete metric spaces are made use of as an important mathematical tool, both in defining and in comparing the various models.