Abstract
We present the implementation of a universal unification algorithm for the class of equational theories induced by macro tree transducers, on an abstract machine called checking-graph nested-stack twin machine (for short: cg-nst machine). This implementation extends an implementation of call-by-name reduction by adding mechanisms for unification. For this purpose, the cg-nst machine consists of two nested-stacks. On each of them, one of the two terms which should be unified, is evaluated. Unification is realized by decomposition steps which are applied as early as possible. Thus, the non-unifiability of the two terms is detected as early as possible which increases the efficiency of the implementation.
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The work of the author is supported by the Deutsche Forschungsgemeinschaft (DFG).
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Faßbender, H. (1993). Implementation of a universal unification algorithm for macro tree transducers. In: Ésik, Z. (eds) Fundamentals of Computation Theory. FCT 1993. Lecture Notes in Computer Science, vol 710. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-57163-9_18
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DOI: https://doi.org/10.1007/3-540-57163-9_18
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