Rewrite Closure for Ground and Cancellative AC Theories
نویسنده
چکیده
Given a binary relation IE ∪ IR on the set of ground terms over some signature, we define an abstract rewrite closure for IE ∪ IR. An abstract rewrite closure can be interpreted as a specialized ground tree transducer (pair of bottom-up tree automata) and can be used to efficiently decide the reachability relation →IE∪IE−∪IR. It is constructed using a completion like procedure. Correctness is established using proof ordering techniques. The procedure is extended, in a modular way, to deal with signatures containing cancellative associative commutative function
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