Relating the solutions of nominal unification and pattern unification
نویسنده
چکیده
Levy and Villaret proposed a translation of nominal unification problems to higher-order pattern unification problems and showed that unifiability is preserved by this translation. We take this further by showing correspondences between solutions of corresponding pattern unification problems and nominal unification problems. The notions of correspondence are non-trivial, and require careful definition of the translation of the substitution and a notion of permutative equivalence of solutions in λ-calculus. We also discover an interesting new notion of ‘capturable atoms’ of a nominal term.
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