T1.T
include Monoid.Base
type t
val zero : t
zero an element that is neutral to plus
zero
plus
val plus : t -> t -> t
plus x y an associative operation.
plus x y
val concat : t list -> t
concat xs reduces xs to using plus
concat xs
xs
val (@@) : t -> t -> t
x @@ y is plus x y
x @@ y