Module MoreLabels.Map

module Map: sig .. end

Association tables over ordered types.

This module implements applicative association tables, also known as finite maps or dictionaries, given a total ordering function over the keys. All operations over maps are purely applicative (no side-effects). The implementation uses balanced binary trees, and therefore searching and insertion take time logarithmic in the size of the map.

For instance:

       module IntPairs =
         struct
           type t = int * int
           let compare (x0,y0) (x1,y1) =
             match Stdlib.compare x0 x1 with
                 0 -> Stdlib.compare y0 y1
               | c -> c
         end

       module PairsMap = Map.Make(IntPairs)

       let m = PairsMap.(empty |> add (0,1) "hello" |> add (1,0) "world")
     

This creates a new module PairsMap, with a new type 'a PairsMap.t of maps from int * int to 'a. In this example, m contains string values so its type is string PairsMap.t.

module type OrderedType = sig .. end

module type S = sig .. end

module Make: 
functor (Ord : OrderedType) -> S 
    with type key = Ord.t
     and type 'a t = 'a Map.Make(Ord).t