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arXiv · 2506.22047

Shape Preserving Tree Transducers

Paul Gallot·Sebastian Maneth
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Abstract

It is shown that shape preservation is decidable for top-down tree transducers, bottom-up tree transducers, and for compositions of total deterministic macro tree transducers. Moreover, if a transducer is shape preserving, then it can be brought into a particular normal form, where every input node creates exactly one output node.

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Paul Gallot, Sebastian Maneth. 2025-06-27. Shape Preserving Tree Transducers. https://arxiv.org/abs/2506.22047

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