Armin Kühnemann

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Many functional programs with accumulating parameters are contained in the class of macro tree transducers. We present a program transformation technique that can be used to solve the efficiency problems due to creation and consumption of intermediate data structures in compositions of such functions, where classical deforestation techniques fail. In order(More)
We compare transformations for the elimination of intermediate results in rst-order functional programs. We choose the well known deforestation technique of Wadler and composition techniques from the theory of tree transducers, of which the implementation of functional programs yet does not take advantage. We identify syntactic classes of function(More)
Several induction theorem provers were developed to verify functional programs mechanically. Unfortunately, automatic verification often fails for functions with accumulating arguments. Using concepts from the theory of tree transducers and extending on earlier work, the paper develops automatic transformations from accumulative functional programs into(More)
In this appendix to the article “Composition of functions with accumulating parameters” we prove Theorem 5.2 of that paper, showing that Construction 5.1 produces an mtt that is equivalent to the composition of the two given ones. Firstly, we will formalise the idea of “walking upwards” in the intermediate result to obtain the context parameters of calls of(More)
In this paper we introduce a new formal model for the concept of syntaxdirected semantics, calledmacro attributed tree transducer (for short: mat tree transducer). This model is based on (noncircular) attributed tree transducers and on macro tree transducers. In the first type of transducer, semantic values are computed by means of meaning names called(More)
A. Middeldorp (Ed.): Rewriting Techniques and Applications. Proceedings. LNCS 2051, pp. 154–168, 2001. c © Springer-Verlag Berlin Heidelberg 2001 Abstract. We study the problem to transform functional programs, which intensively use append functions (like inefficient list reversal), into programs, which use accumulating parameters instead (like efficient(More)
The concept of attributed tree transducer is a formal model for studying properties of attribute grammars In this paper for output languages of noncircular producing and visiting attributed tree transducers we introduce and prove a pumping lemma We ap ply this pumping lemma to gain two results there is no noncircular producing and visiting attributed tree(More)