module Sigs:sig
..end
module type SEQUENT =sig
..end
module type DEFS =sig
..end
module type NODE =sig
..end
module type PROOF =sig
..end
module type SEQTACTICS =sig
..end
module type PROOFRULE =sig
..end
module type ABDRULE =sig
..end
module type PROVER =sig
..end
module type ABDUCER =sig
..end