Map.3o man page

Map — Association tables over ordered types.


Module 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 x0 x1 with 0 -> 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

Input signature of the functor Map.Make .

module type S = sig end

Output signature of the functor Map.Make .

module Make : functor (Ord : OrderedType) -> sig end

Functor building an implementation of the map structure given a totally ordered type.


source: 2017-01-12 OCamldoc