Intuitionistic Propositional Checker. This development treats proof search in intuitionistic propositional logic, a fragment of any constructive type theory. We present new and more efficient decision procedures for intuitionistic propositional logic. They themselves are given by (non-formal) constructive proofs. We take one of them to demonstrate that constructive type theory can be used in practice to develop a real, efficient, but error-free proof searcher. This was done by formally proving the decidability of intuitionistic propositional logic in Coq; the proof searcher was automatically extracted.
opam install coq-ipc.8.5.0