Type Alias ResolveCountryCode<C>

ResolveCountryCode: C extends string
    ? Uppercase<C> extends keyof ParseResultMap
        ? Uppercase<C>
        : Uppercase<C> extends keyof CountryAliasMap
            ? CountryAliasMap[Uppercase<C>]
            : never
    : never

The alpha-3 key a country code resolves to, like the registry does at runtime: case-insensitive, aliases included. never for a code that is not built in.