Abstract
Second-order unification is undecidable in general. Miller showed that unification of so-called higher-order patterns is decidable and unitary. We show that the unification of a linear higher-order pattern s with an arbitrary second-order term that shares no variables with s is decidable and finitary. A few extensions of this unification problem are still decidable: unifying two second-order terms, where one term is linear, is undecidable if the terms contain bound variables but decidable if they don't.
Research supported by the DFG under grant Br 887/4-2, Deduktive Programmentwicklung and by ESPRIT WG 6028, CCL.
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© 1994 Springer-Verlag Berlin Heidelberg
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Prehofer, C. (1994). Decidable higher-order unification problems. In: Bundy, A. (eds) Automated Deduction — CADE-12. CADE 1994. Lecture Notes in Computer Science, vol 814. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-58156-1_46
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DOI: https://doi.org/10.1007/3-540-58156-1_46
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