Proof.StepSourceAn inference step is composed of a set of premises, a rule, a status (theorem/trivial/equisatisfiable…), and is used to deduce new result using these premises and metadata.
A single step can be used to deduce several results.
distance_to_conjecture p returns None if p has no ancestor that is a conjecture (including p itself). It returns Some d if d is the distance, in the proof graph, to the closest conjecture ancestor of p