module Monad: Monadmodule type Basic =sig..end
module type Infix =sig..end
module type S =sig..end
module Make(M:Basic):sig..end
module type Basic2 =sig..end
module type Infix2 =sig..end
module type S2 =sig..end
module Check_S2_refines_S(X:S):sig..end
module Make2(M:Basic2):sig..end