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arXiv · 2002.09307

First-order tree-to-tree functions

Mikołaj Bojańczyk·Amina Doumane
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Abstract

We study tree-to-tree transformations that can be defined in first-order logic or monadic second-order logic. We prove a decomposition theorem, which shows that every transformation can be obtained from prime transformations, such as tree-to-tree homomorphisms or pre-order traversal, by using combinators such as function composition.

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Mikołaj Bojańczyk, Amina Doumane. 2023-01-30. First-order tree-to-tree functions. https://arxiv.org/abs/2002.09307

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