A Decision Algorithm for Stratified Context Unification

Context uniication is a variant of second-order uniication and also a generalization of string uniication. Currently it is not known whether context uniication is decidable. An expressive fragment of context uniication is stratiied context uniication. Recently, it turned out that stratiied context uniication and one-step rewrite constraints are equivalent. This paper contains a description of a decision algorithm SCU for strat-iied context uniication together with a proof of its correctness, which shows decidability of stratiied context uniication as well as of satissa-bility of one-step rewrite constraints.

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