Monad.Of_monad3
The same as S
except the monad type has three arguments. The second and third are always just passed through.
module M : sig ... end
module Let_syntax : sig ... end
module Monad_infix : sig ... end
Same as Infix, except the monad type has three arguments. The second and third are always just passed through.
val return : 'a -> ('a, _, _) M.t