Non-E-Overlapping, Weakly Shallow, and Non-Collapsing TRSs are Confluent
نویسندگان
چکیده
A term is weakly shallow if each defined function symbol occurs either at the root or in the ground subterms, and a term rewriting system is weakly shallow if both sides of a rewrite rule are weakly shallow. This paper proves that non-E-overlapping, weakly-shallow, and noncollapsing term rewriting systems are confluent by extending reduction graph techniques in our previous work [SO10] with towers of expansions.
منابع مشابه
Non - E - overlapping and weakly shallow TRSs are confluent ( Extended abstract ) Masahiko Sakai
Confluence of term rewriting systems (TRSs) is undecidable, even for flat TRSs [MOJ06] or length-two string rewrite systems [SW08]. Two decidable subclasses are known: right-linear and shallow TRSs by tree automata techniques [GT05] and terminating TRSs [KB70]. Most of sufficient conditions are for either terminating TRSs [KB70] (extended to TRSs with relative termination [HA11, KH12]) or leftl...
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