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arXiv · 2011.09507

Efficient Full Higher-Order Unification

Petar Vukmirović·Alexander Bentkamp·Visa Nummelin
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Abstract

We developed a procedure to enumerate complete sets of higher-order unifiers based on work by Jensen and Pietrzykowski. Our procedure removes many redundant unifiers by carefully restricting the search space and tightly integrating decision procedures for fragments that admit a finite complete set of unifiers. We identify a new such fragment and describe a procedure for computing its unifiers. Our unification procedure, together with new higher-order term indexing data structures, is implemented in the Zipperposition theorem prover. Experimental evaluation shows a clear advantage over Jensen and Pietrzykowski's procedure.

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Petar Vukmirović, Alexander Bentkamp, Visa Nummelin. 2020-11-18. Efficient Full Higher-Order Unification. https://doi.org/10.46298/lmcs-17(4%3A18)2021

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