@spec fallback_locale_names(Cldr.LanguageTag.t() | Cldr.Locale.locale_reference()) ::
  {:ok, [Cldr.Locale.locale_name(), ...]} | {:error, {module(), String.t()}}

Returns the list of fallback locale names, starting with the provided locale name.

Fallbacks are a list of locate names which can be used to resolve translation or other localization data if such localised data does not exist for this specific locale..

Arguments

• locale_name is any locale name returned by Literature.known_locale_names/0

Returns

• {:ok, list_of_locale_names} or

• {:error, {exception, reason}}

Examples

iex> Literature.Locale.fallback_locale_names(:"fr-CA")
{:ok, [:"fr-CA", :fr, :und]}

# Fallbacks are typically formed by progressively
# stripping variant, territory and script from the
# given locale name. But not always - there are
# certain fallbacks that take a different path.

iex> Literature.Locale.fallback_locale_names(:nb)
{:ok, [:nb, :no, :und]}

@spec fallback_locales(Cldr.LanguageTag.t() | Cldr.Locale.locale_reference()) ::
  {:ok, [Cldr.LanguageTag.t(), ...]} | {:error, {module(), String.t()}}

Returns the list of fallback locales, starting with the provided locale name.

Fallbacks are a list of locate names which can be used to resolve translation or other localization data if such localised data does not exist for this specific locale.

Arguments

• locale_name is any locale name returned by Literature.known_locale_names/0

Returns

• {:ok, list_of_locales} or

• {:error, {exception, reason}}

Examples

Literature.Locale.fallback_locales(:"fr-CA")
=> {:ok,
     [#Cldr.LanguageTag<fr-CA [validated]>, #Cldr.LanguageTag<fr [validated]>,
      #Cldr.LanguageTag<und [validated]>]}

# Fallbacks are typically formed by progressively
# stripping variant, territory and script from the
# given locale name. But not always - there are
# certain fallbacks that take a different path.

Literature.Locale.fallback_locales(:nb))
=> {:ok,
     [#Cldr.LanguageTag<nb [validated]>, #Cldr.LanguageTag<no [validated]>,
      #Cldr.LanguageTag<und [validated]>]}

@spec locale_for_territory(Cldr.Locale.territory_code()) ::
  {:ok, Cldr.LanguageTag.t()} | {:error, {module(), String.t()}}

Returns the "best fit" locale for a given territory.

Using the population percentage data from CLDR, the language most commonly spoken in the given territory is used to form a locale name which is then validated against the given backend.

First a territory-specific locale is validated and if that fails, the base language only is validate.

For example, if the territory is AU then then the language most spoken is "en". First, the locale "en-AU" is validated and if that fails, "en" is validated.

Arguments

• territory is any ISO 3166 Alpha-2 territory code that can be validated by Cldr.validate_territory/1

Returns

• {:ok, language_tag} or

• {:error, {exception, reason}}

Examples

iex> Literature.Locale.locale_for_territory(:AU) Elixir.Literature.validate_locale(:"en-AU")

iex> Literature.Locale.locale_for_territory(:US) Elixir.Literature.validate_locale(:"en-US")

iex> Literature.Locale.locale_for_territory(:ZZ) {:error, {Cldr.UnknownTerritoryError, "The territory :ZZ is unknown"}}

@spec locale_from_host(String.t(), Keyword.t()) ::
  {:ok, Cldr.LanguageTag.t()} | {:error, {module(), String.t()}}

Returns a "best fit" locale for a host name.

Arguments

• host is any valid host name

• options is a keyword list of options. The default is [].

Options

• :tlds is a list of territory codes as upper-cased atoms that are to be considered as top-level domains. See Cldr.Locale.locale_from_host/2 for the default list.

Returns

• {:ok, langauge_tag} or

• {:error, {exception, reason}}

Notes

Certain top-level domains have become associated with content underlated to the territory for who the domain is registered. Therefore Google (and perhaps others) do not associate these TLDs as belonging to the territory but rather are considered generic top-level domain names.

Examples

iex> Literature.Locale.locale_from_host "a.b.com.au"
Elixir.Literature.validate_locale(:"en-AU")

iex> Literature.Locale.locale_from_host("a.b.com.tv")
{:error,
 {Cldr.UnknownLocaleError, "No locale was identified for territory \"tv\""}}

iex> Literature.Locale.locale_from_host("a.b.com")
{:error,
 {Cldr.UnknownLocaleError, "No locale was identified for territory \"com\""}}

Returns the script direction for a locale.

Arguments

• language_tag is any language tag returned by Cldr.Locale.new/2 or any locale_name returned by Cldr.known_locale_names/1.

Returns

• The script direction which is either :ltr (for left-to-right scripts) or :rtl (for right-to-left scripts).

Examples

iex> Literature.Locale.script_direction_from_locale "en-US"
:ltr

iex> Literature.Locale.script_direction_from_locale :ar
:rtl

@spec territory_from_host(String.t()) ::
  {:ok, Cldr.Locale.territory_code()} | {:error, {module(), String.t()}}

Returns the last segment of a host that might be a territory.

Arguments

• host is any valid host name

Returns

• {:ok, territory} or

• {:error, {exception, reason}}

Examples

iex> Cldr.Locale.territory_from_host("a.b.com.au")
{:ok, :AU}

iex> Cldr.Locale.territory_from_host("a.b.com")
{:error,
 {Cldr.UnknownLocaleError, "No locale was identified for territory \"com\""}}

@spec territory_from_locale(Cldr.LanguageTag.t() | Cldr.Locale.locale_name()) ::
  Cldr.Locale.territory_code() | {:error, {module(), String.t()}}

Returns the territory from a language tag or locale name.

Arguments

• locale is any language tag returned by Literature.Locale.new/1 or a locale name in the list returned by Literature.known_locale_names/0

Returns

• A territory code as an atom

Examples

iex> Literature.Locale.territory_from_locale "en-US"
:US

iex> Literature.Locale.territory_from_locale "en-US-u-rg-GBzzzz"
:GB

@spec timezone_from_locale(Cldr.LanguageTag.t() | Cldr.Locale.locale_name()) ::
  String.t() | {:error, {module(), String.t()}}

Returns the time zone from a language tag or locale name.

Arguments

• locale is any language tag returned by Literature.Locale.new/1 or a locale name in the list returned by Literature.known_locale_names/0

Returns

• A time zone ID as a string or

• :error if no time zone can be determined

Examples

iex> Literature.Locale.timezone_from_locale "en-US-u-tz-ausyd"
"Australia/Sydney"