---
name: "Map.OrderedType"
section: "3o"
platform: "linux"
package: "ocaml"
version: "5.5.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/Map.OrderedType"
---

# Map.OrderedType(3o)

Input signature of the functor Map.Make.

## NAME

Map.OrderedType - Input signature of the functor Map.Make.

## Module type

Module type   Map.OrderedType

## Documentation

Module type **OrderedType**\
  \=  **sig end**

Input signature of the functor  **Map.Make** .

*type t*

The type of the map keys.

*val compare* :  **t -\> t -\> int**

A total ordering function over the keys. This is a two-argument function  **f** such that **f e1 e2** is zero if the keys  **e1** and  **e2** are equal, **f e1 e2** is strictly negative if  **e1** is smaller than  **e2** , and  **f e1 e2** is strictly positive if  **e1** is greater than  **e2** . Example: a suitable ordering function is the generic structural comparison function  **compare** .