package ISO3166

ISO3166

This library provides an interface to the ISO3166 standard. This defines "country codes". These are short, unique codes that identify a given country. In the ISO3166-1 standard there are three kinds of codes.

• ISO3166.alpha2: This is a two-letter country code.
• ISO3166.alpha3: This is a three-letter country code. This is usually more closely related to the country's name.
• ISO3166.numeric: This is a three-digit country code which is useful for systems using non-Latin scripts.

Usage

Public APIs

The library provides a few different ways of interacting with this information. One useful way to use the library is when wrapping public APIs that might uses alpha2 to refine access to some resource in a country-specific way. You might then wish to type this in you OCaml API.

val get_population : ISO3166.alpha2 -> int

Which might then have an implementation along the lines of:

let get_population alpha2 =
  Client.get (Endpoint.population ^ "/" ^ ISO3166.alpha2_to_string alpha2)

Low-level Country Information

The library also encodes all of the country information in the ISO3166.Country module. This could be used as a way to provide another means to getting country-specific information.

For example, you could extract the numeric code but ask a user to provide a ISO3166.Country.t instead.

let num_fr = ISO3166.Country.fr |> ISO3166.Country.numeric |> ISO3166.numeric_to_string

In this small example num_fr will be "250".