How to Remove the Look-Ahead of Top-Down Tree Transducers
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چکیده
For a top-down tree transducer with regular look-ahead we introduce the notion of difference bound, which is a number bounding the difference in output height for any two look-ahead states of the transducer. We present an algorithm that, for a given transducer with a known difference bound, decides whether it is equivalent to a transducer without regular look-ahead, and constructs such a transducer if the answer is positive. All transducers are total and deterministic.
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تاریخ انتشار 2014