Confluence of nearly orthogonal infinitary term rewriting systems
نویسنده
چکیده
We give a relatively simple coinductive proof of confluence, modulo equivalence of root-active terms, of nearly orthogonal infinitary term rewriting systems. Nearly orthogonal systems allow certain root overlaps, but no non-root overlaps. Using a slightly more complicated method we also show confluence modulo equivalence of hypercollapsing terms. The condition we impose on root overlaps is similar to the condition used by Toyama in the context of finitary rewriting. 1998 ACM Subject Classification F.4.2 Grammars and Other Rewriting Systems
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