Deterministic top-down tree transducers with iterated look-ahead
نویسندگان
چکیده
منابع مشابه
Deterministic Top-Down Tree Transducers with Iterated Lookahead
It is known that by iterating the look-ahead tree languages for deterministic topdown tree automata, more and more powerful recognizing devices are obtained. Let DR0 = DR, where DR is the class of all tree languages recognizable by deterministic top-down tree automata, and let, for n 1, DRn be the class of all tree languages recognizable by deterministic top-down tree automata with DRn 1 lookah...
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Top-down tree transducers are a convenient formalism for describing tree transformations. They can be equipped with regular look-ahead, which allows them to inspect a subtree before processing it. In certain cases, such a look-ahead can be avoided and the transformation can be realized by a transducer without look-ahead. Removing the look-ahead from a transducer, if possible, is technically hig...
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A composition procedure for linear and nondeleting extended top-down tree transducers is presented. It is demonstrated that the new procedure is more widely applicable than the existing methods. In general, the result of the composition is an extended top-down tree transducer that is no longer linear or nondeleting, but in a number of cases these properties can easily be recovered by a post-pro...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 1995
ISSN: 0304-3975
DOI: 10.1016/0304-3975(94)00111-u