AC-Unification of Higher-Order Patterns
نویسندگان
چکیده
We present a complete algorithm for the uniication of higher-order patterns modulo the associative-commutative theory of some constants +1; : : : ; +n. Given an AC-uniication problem over higher-order patterns, the output of the algorithm is a nite set DAG solved forms 9], constrained by some exible-exible equations with the same head on both sides. Indeed, in the presence of AC constants, such equations are always solvable, but they have no minimal complete set of uniiers 13]. We prove that the algorithm terminates, is sound, and that any solution of the original uniication problem is an instance of one of the computed solutions which satisses the constraints.
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