Better Automation for TLA+ Proofs

Article court pour les 31e Journées Francophones des Langages Applicatifs (JFLA 2020)International audienceTLA+ is a specification language based on traditional untyped set theory. It is equipped with a set of tools, including the TLA+ proof system TLAPS, which uses trusted back-end solvers to handle individual proof steps-referred to as "proof obligations". As most solvers rely on and benefit from typed formalisms, types are first reconstructed for the obligations; however, the current encoding into the SMT-LIB format does not exploit all of this type information. In this paper, we present motivations for a more pervasive usage of types at an intermediate representation of TLA+ proof obligations, and describe work in progress on several improvements of TLAPS: a type-driven SMT encoding, a tactic for instantiation hints, and type annotations for the language. We conclude with some perspectives for future work