Abstract
Linear Second-Order Unification and Context Unification are closely related problems. However, their equivalence was never formally proved. Context unification is a restriction of linear second-order unification. Here we prove that linear second-order unification can be reduced to context unification with tree-regular constraints.
Decidability of context unification is still an open question. We comment on the possibility that linear second-order unification is decidable, if context unification is, and how to get rid of the tree-regular constraints. This is done by reducing rank-bound tree-regular constraints to word-regular constraints.
The first author is partially supported by the project MODELOGOS founded by the CICYT.
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Levy, J., Villaret, M. (2000). Linear Second-Order Unification and Context Unification with Tree-Regular Constraints. In: Bachmair, L. (eds) Rewriting Techniques and Applications. RTA 2000. Lecture Notes in Computer Science, vol 1833. Springer, Berlin, Heidelberg. https://doi.org/10.1007/10721975_11
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DOI: https://doi.org/10.1007/10721975_11
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