Decidable Higher-Order Uni cation Problems
نویسنده
چکیده
Second-order uniication is undecidable in general. Miller showed that uniication of so-called higher-order patterns is decidable and unitary. We show that the uniication of a linear higher-order pattern s with an arbitrary second-order term that shares no variables with s is decidable and nitary. A few extensions of this uniication 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.
منابع مشابه
Decidable Higher-Order Unification Problems
Second order uni cation is undecidable in general Miller showed that uni cation of so called higher order patterns is decidable and unitary We show that the uni cation of a linear higher order pat tern s with an arbitrary second order term that shares no variables with s is decidable and nitary A few extensions of this uni cation problem are still decidable unifying two second order terms where...
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