.TH "MoreLabels.Map" 3 2024-05-31 OCamldoc "OCaml library"
.SH NAME
MoreLabels.Map \- no description
.SH Module
Module   MoreLabels.Map
.SH Documentation
.sp
Module
.BI "Map"
 : 
.B sig end

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.sp

.sp
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.PP
Association tables over ordered types\&.
.sp
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\&.
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For instance:
.EX
.ft B
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\&       module IntPairs =
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\&         struct
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\&           type t = int * int
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\&           let compare (x0,y0) (x1,y1) =
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\&             match Stdlib\&.compare x0 x1 with
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\&                 0 \-> Stdlib\&.compare y0 y1
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\&               | c \-> c
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\&         end
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\&
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\&       module PairsMap = Map\&.Make(IntPairs)
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\&
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\&       let m = PairsMap\&.(empty |> add (0,1) "hello" |> add (1,0) "world")
.br
\&     
.ft R
.EE
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This creates a new module 
.ft B
PairsMap
.ft R
, with a new type 
.ft B
\&'a PairsMap\&.t
.ft R
of maps from 
.ft B
int * int
.ft R
to 
.ft B
\&'a
.ft R
\&. In this example, 
.ft B
m
.ft R
contains 
.ft B
string
.ft R
values so its type is 
.ft B
string PairsMap\&.t
.ft R
\&.
.PP
.I module type OrderedType = 
.B sig end

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Input signature of the functor 
.ft B
MoreLabels\&.Map\&.Make
.ft R
\&.

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.I module type S = 
.B sig end

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Output signature of the functor 
.ft B
MoreLabels\&.Map\&.Make
.ft R
\&.

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

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

.sp