On the Merits of Temporal Testers

The paper discusses the merits of temporal testers, which can serve as a compositional basis for automata construction corresponding to temporal formulas in the context of LTL, PSL, and MITL logics. Temporal testers can be viewed as (non-deterministic) transducers that, at any point, output a boolean value which is 1 iff the corresponding temporal formula holds starting at the current position. The main advantage of testers, compared to acceptors (such as Büchi automata) is their compositionality. Namely, a tester for a compound formula can be constructed out of the testers for its sub-formulas. Besides providing the construction of testers for formulas specified in LTL, PSL, and MITL, the paper also presents a general overview of the tester methodology, and highlights some of the unique features and applications of transducers including compositional deductive verification of LTL properties.