module type Basic = sig ... endmodule type S = sig ... endThis functor extends the basic definition of a monoid by adding a convenient operator synonym ( @ ) = combine, as well as derived functions reduce and map_reduce.
The string concatenation monoid with empty = "" and combine = ( ^ ).
The list monoid with empty = [] and combine = ( @ ).
module Appendable_list
(M : sig ... end) :
S with type t = M.t Appendable_list.tThe list monoid with empty = [] and combine = ( @ ).
The addition monoid with empty = zero and combine = ( + ).
The multiplication monoid with empty = one and combine = ( * ).
The union monoid with empty = M.empty and combine = M.union.
The product of monoids where pairs are combined component-wise.
module Product3
(A : sig ... end)
(B : sig ... end)
(C : sig ... end) :
S with type t = A.t * B.t * C.tSame as Product but for 3 monoids.
Functions that return a monoid form the following monoid:
module Endofunction : sig ... endEndofunctions, i.e., functions of type t -> t, form two monoids.