Module Monoid.MakeSource

This functor extends the basic definition of a monoid by adding a convenient operator synonym ( @ ) = combine, as well as derived functions reduce and map_reduce.

Parameters

module M : Basic

Signature

type t = M.t
val empty : t

Must be the identity of combine:

  • combine empty t = t
  • combine t empty = t
val combine : t -> t -> t

Must be associative:

  • combine a (combine b c) = combine (combine a b) c
Sourcemodule O : sig ... end
Sourceval reduce : t list -> t
Sourceval map_reduce : f:('a -> t) -> 'a list -> t