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arXiv · 2603.11648

Visibly Recursive Automata

Kévin Dubrulle·Véronique Bruyère·Guillermo A. Pérez·Gaëtan Staquet
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Abstract

As an alternative to visibly pushdown automata, we introduce visibly recursive automata (VRAs), composed of a set of classical automata that can call each other. VRAs are a strict extension of so-called systems of procedural automata, a model proposed by Frohme and Steffen. We study the complexity of standard language-theoretic operations and classical decision problems for VRAs. Since the class of deterministic VRAs forms a strict subclass in terms of expressiveness, we propose a (weaker) notion that does not restrict expressive power and which we call codeterminism. Codeterminism comes with many desirable algorithmic properties that we demonstrate by using it, e.g., as a stepping stone towards implementing complementation of VRAs.

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Kévin Dubrulle, Véronique Bruyère, Guillermo A. Pérez, Gaëtan Staquet. 2026-05-11. Visibly Recursive Automata. https://arxiv.org/abs/2603.11648

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