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.
The work of the author is supported by the Deutsche Forschungsgemeinschaft (DFG).
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References
B. Courcelle and P. Franchi-Zannettacci. Attribute grammars and recursive program schemes I, II. Theoret. Comput. Sci., 17:163–191 and 235–257, 1982.
R. Echahed. On completeness of narrowing strategies. In CAAP88, pages 89–101. Springer-Verlag, 1988. LNCS 299.
J. Engelfriet. Some open questions and recent results on tree transducers and tree languages. In R.V. Book, editor, Formal language theory; perspectives and open problems. New York, Academic Press, 1980.
J. Engelfriet and H. Vogler. Macro tree transducers. Journal of Computer and System Sciences, 31:71–145, 1985.
J. Engelfriet and H. Vogler. Pushdown machines for the macro tree transducer. Theoretical Computer Science, 42:251–368, 1986.
H. Faßbender and H. Vogler. An implementation of syntax directed functional programming on nested-stack machines. Formal Aspects of Computing, 4:341–375, 1992.
H. Faßbender and H. Vogler. A universal unification algorithm based on unification-driven leftmost outermost narrowing. Technical Report 07, University of Ulm, Fakultät für Informatik, Oberer Eselsberg, W-7900 Ulm, Germany, 1992.
Z. Fülöp, F. Herrmann, S. Vagvölgyi, and H. Vogler. Tree transducers with external functions. Theoretical Computer Science, 108:185–236, 1993.
K. Gladitz, H. Faßbender, and H. Vogler. Compiler-based implementation of syntax directed functional programming. Technical Report 10, Aachen University of Technology, Fachgruppe Informatik, Ahornstr. 55, W-5100 Aachen, FRG, 1991.
J.M. Hullot. Canonical forms and unification. In Proceedings of the 5th conference on automated deduction, LNCS 87, pages 318–334. Springer-Verlag, 1980.
A. Martelli and U. Montanari. An efficient unification algorithm. ACM Transactions on Programming Languages Systems, 4:258–282, 1982.
M. Rodriguez-Artalejo and H. Vogler. Note on a narrowing machine for syntax directed BABEL. Technical Report 19, Aachen University of Technology, Fachgruppe Informatik, Ahornstr. 55, W-5100 Aachen, FRG, 1989.
J.H. Siekmann. Unification theory. Journal of Symbolic Computation, 7:207–274, 1989.
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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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