English

On non-structural subtype entailment

Programming Languages 2021-12-21 v2

Abstract

We prove that the non-structural subtype entailment problem for finite and regular type expressions is in PSPACE. In this way we close a decidability and complexity gap pending since 1996.

Cite

@article{arxiv.2109.02458,
  title  = {On non-structural subtype entailment},
  author = {Aleksy Schubert},
  journal= {arXiv preprint arXiv:2109.02458},
  year   = {2021}
}

Comments

The paper contains error in formulation of Lemma 5.5, which invalidates the further construction

R2 v1 2026-06-24T05:42:58.792Z