Return the default number system type name.

Currently this is :default. Note that this is not the number system itself but the type of the number system. It can be used to find the default number system for a given locale with number_systems_for(locale)[default_number_system()].

Example

iex> Cldr.Number.System.default_number_system_type
:default

Generate a transliteration map between two character classes

Arguments

• from is any String.t() intended to represent the digits of a number system but that's not a requirement.

• to is any String.t() that is the same length as from intended to represent the digits of a number system.

Returns

• A map where the keys are the graphemes in from and the values are the graphemes in to or

• {:error, {exception, reason}}

Examples

iex> Cldr.Number.System.generate_transliteration_map "0123456789", "9876543210"
%{
  "0" => "9",
  "1" => "8",
  "2" => "7",
  "3" => "6",
  "4" => "5",
  "5" => "4",
  "6" => "3",
  "7" => "2",
  "8" => "1",
  "9" => "0"
}

iex> Cldr.Number.System.generate_transliteration_map "0123456789", "987654321"
{:error,
 {ArgumentError, "\"0123456789\" and \"987654321\" aren't the same length"}}

See Cldr.known_number_system_types/1.

See Cldr.known_number_systems/0.

@spec number_system_digits(system_name()) ::
  {:ok, String.t()} | {:error, {module(), String.t()}}

Returns {:ok, digits} for a number system, or an {:error, message} if the number system is not known.

Arguments

• system_name is any number system name returned by Cldr.known_number_systems/0 or a number system type returned by Cldr.known_number_system_types/0

Returns

• {:ok, string_of_digits} or

• {:error, {exception, reason}}

Examples

iex> Cldr.Number.System.number_system_digits(:latn)
{:ok, "0123456789"}

iex> Cldr.Number.System.number_system_digits(:nope)
{:error, {Cldr.UnknownNumberSystemError, "The number system :nope is not known or does not have digits"}}

@spec number_system_digits!(system_name()) :: String.t() | no_return()

Returns digits for a number system, or raises an exception if the number system is not know.

Arguments

• system_name is any number system name returned by Cldr.known_number_systems/0 or a number system type returned by Cldr.known_number_system_types/0

Returns

• A string of the number systems digits or

• raises an exception

Examples

iex> Cldr.Number.System.number_system_digits! :latn
"0123456789"

Cldr.Number.System.number_system_digits! :nope
** (Cldr.UnknownNumberSystemError) The number system :nope is not known or does not have digits

@spec number_system_for(Cldr.Locale.locale_reference(), system_name(), Cldr.backend()) ::
  {:ok, map()} | {:error, {module(), String.t()}}

Returns the actual number system from a number system type.

Arguments

• locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag struct returned by Cldr.Locale.new!/2

• system_name is any number system name returned by Cldr.known_number_systems/0 or a number system type returned by Cldr.known_number_system_types/0

• backend is any Cldr backend. That is, any module that contains use Cldr

Returns

• {:ok, number_system_map} or

• {:error, {exception, reason}}

Notes

This function will decode a number system type into the actual number system. If the number system provided can't be decoded it is returned as is.

Examples

iex> Cldr.Number.System.number_system_for "th", :latn, TestBackend.Cldr
{:ok, %{digits: "0123456789", type: :numeric}}

iex> Cldr.Number.System.number_system_for "en", :default, TestBackend.Cldr
{:ok, %{digits: "0123456789", type: :numeric}}

iex> Cldr.Number.System.number_system_for "he", :traditional, TestBackend.Cldr
{:ok, %{rules: "hebrew", type: :algorithmic}}

iex> Cldr.Number.System.number_system_for "en", :finance, TestBackend.Cldr
{
  :error,
  {
    Cldr.UnknownNumberSystemError,
    "The number system :finance is unknown for the locale named :en. Valid number systems are %{default: :latn, native: :latn}"
  }
}

iex> Cldr.Number.System.number_system_for "en", :native, TestBackend.Cldr
{:ok, %{digits: "0123456789", type: :numeric}}

@spec number_system_from_locale(Cldr.Locale.locale_reference()) :: system_name()

Returns the number system from a language tag or locale name.

Arguments

• locale is any language tag returned be Cldr.Locale.new/2

Returns

• A number system name as an atom

Examples

iex> {:ok, locale} = MyApp.Cldr.validate_locale("en-US-u-nu-thai")
iex> Cldr.Number.System.number_system_from_locale(locale)
:thai

iex> {:ok, locale} = MyApp.Cldr.validate_locale("en-US")
iex> Cldr.Number.System.number_system_from_locale locale
:latn

iex> Cldr.Number.System.number_system_from_locale("ar")
:arab

@spec number_system_from_locale(Cldr.Locale.locale_reference(), Cldr.backend()) ::
  system_name()

Returns the default number system from a language tag or locale name.

Arguments

• locale is any language tag returned be Cldr.Locale.new/2 or a locale name in the list returned by Cldr.known_locale_names/1

• backend is any Cldr backend. That is, any module that contains use Cldr

Returns

• A number system name as an atom

Examples

iex> Cldr.Number.System.number_system_from_locale "en-US-u-nu-thai", MyApp.Cldr
:thai

iex> Cldr.Number.System.number_system_from_locale :"en-US", MyApp.Cldr
:latn

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

Returns the names of the number systems available for a locale or an {:error, message} tuple if the locale is not known.

Arguments

• locale is any locale returned by Cldr.Locale.new!/2 or a Cldr.LanguageTag struct

• backend is any Cldr backend. That is, any module that contains use Cldr

Examples

iex> Cldr.Number.System.number_system_names_for("en", TestBackend.Cldr)
{:ok, [:latn]}

iex> Cldr.Number.System.number_system_names_for("th", TestBackend.Cldr)
{:ok, [:latn, :thai]}

iex> Cldr.Number.System.number_system_names_for("he", TestBackend.Cldr)
{:ok, [:latn, :hebr]}

iex> Cldr.Number.System.number_system_names_for("zz", TestBackend.Cldr)
{:error, {Cldr.InvalidLanguageError, "The language \"zz\" is invalid"}}

@spec number_system_names_for!(Cldr.Locale.locale_reference(), Cldr.backend()) ::
  [system_name()] | no_return()

Returns the names of the number systems available for a locale or an {:error, message} tuple if the locale is not known.

Arguments

• locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag struct returned by Cldr.Locale.new!/2

• backend is any Cldr backend. That is, any module that contains use Cldr

Examples

iex> Cldr.Number.System.number_system_names_for!("en", TestBackend.Cldr)
[:latn]

iex> Cldr.Number.System.number_system_names_for!("th", TestBackend.Cldr)
[:latn, :thai]

iex> Cldr.Number.System.number_system_names_for!("he", TestBackend.Cldr)
[:latn, :hebr]

@spec number_systems() :: map()

Return a map of all CLDR number systems and definitions.

Example

iex> Cldr.Number.System.number_systems |> Enum.count
88

@spec number_systems_for(Cldr.Locale.locale_reference(), Cldr.backend()) ::
  {:ok, map()} | {:error, {module(), String.t()}}

Returns the number systems available for a locale or {:error, message} if the locale is not known.

Arguments

• locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag struct returned by Cldr.Locale.new!/2

• backend is any Cldr backend. That is, any module that contains use Cldr

Examples

iex> Cldr.Number.System.number_systems_for :en
{:ok, %{default: :latn, native: :latn}}

iex> Cldr.Number.System.number_systems_for :th
{:ok, %{default: :latn, native: :thai}}

iex> Cldr.Number.System.number_systems_for "zz", TestBackend.Cldr
{:error, {Cldr.InvalidLanguageError, "The language \"zz\" is invalid"}}

@spec number_systems_for!(Cldr.Locale.locale_reference(), Cldr.backend()) ::
  map() | no_return()

Returns the number systems available for a locale or raises if the locale is not known.

Arguments

• locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag struct returned by Cldr.Locale.new!/2

• backend is any Cldr backend. That is, any module that contains use Cldr. The default is Cldr.default_backend!/0.

Examples

iex> Cldr.Number.System.number_systems_for! "en"
%{default: :latn, native: :latn}

iex> Cldr.Number.System.number_systems_for! "th", TestBackend.Cldr
%{default: :latn, native: :thai}

@spec number_systems_like(
  Cldr.Locale.locale_reference(),
  system_name(),
  Cldr.backend()
) ::
  {:ok, list()} | {:error, {module(), String.t()}}

Returns locale and number systems that have the same digits and separators as the supplied one.

Arguments

• locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag struct returned by Cldr.Locale.new!/2

• system_name is any number system name returned by Cldr.known_number_systems/0 or a number system type returned by Cldr.known_number_system_types/0

• backend is any Cldr backend. That is, any module that contains use Cldr

Returns

Notes

Transliterating between locale & number systems is expensive. To avoid unnecessary transliteration we look for locale and number systems that have the same digits and separators. Typically we are comparing to locale "en" and number system "latn" since this is what the number formatting routines use as placeholders.

Examples

@spec system_name_from(system_name(), Cldr.Locale.locale_reference(), Cldr.backend()) ::
  {:ok, atom()} | {:error, {module(), String.t()}}

Returns a number system name for a given locale and number system reference.

Arguments

• system_name is any number system name returned by Cldr.known_number_systems/0 or a number system type returned by Cldr.known_number_system_types/0

• locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag struct returned by Cldr.Locale.new!/2

• backend is any Cldr backend. That is, any module that contains use Cldr

Notes

Number systems can be references in one of two ways:

• As a number system type such as :default, :native, :traditional and :finance. This allows references to a number system for a locale in a consistent fashion for a given use

• WIth the number system name directly, such as :latn, :arab or any of the other 70 or so

This function dereferences the supplied system_name and returns the actual system name.

Examples

ex> Cldr.Number.System.system_name_from(:default, "en", TestBackend.Cldr)
{:ok, :latn}

iex> Cldr.Number.System.system_name_from("latn", "en", TestBackend.Cldr)
{:ok, :latn}

iex> Cldr.Number.System.system_name_from(:native, "en", TestBackend.Cldr)
{:ok, :latn}

iex> Cldr.Number.System.system_name_from(:nope, "en", TestBackend.Cldr)
{
  :error,
  {Cldr.UnknownNumberSystemError, "The number system :nope is unknown"}
}

Note that return value is not guaranteed to be a valid number system for the given locale as demonstrated in the third example.

@spec system_name_from!(system_name(), Cldr.Locale.locale_reference(), Cldr.backend()) ::
  atom() | no_return()

Returns a number system name for a given locale and number system reference and raises if the number system is not available for the given locale.

Arguments

• system_name is any number system name returned by Cldr.known_number_systems/0 or a number system type returned by Cldr.known_number_system_types/0

• locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag struct returned by Cldr.Locale.new!/2

• backend is any Cldr backend. That is, any module that contains use Cldr

Examples

iex> Cldr.Number.System.system_name_from!(:default, "en", TestBackend.Cldr)
:latn

iex> Cldr.Number.System.system_name_from!("latn", "en", TestBackend.Cldr)
:latn

iex> Cldr.Number.System.system_name_from!(:traditional, "he", TestBackend.Cldr)
:hebr

Number systems that have their own digit characters defined.

@spec to_system(Cldr.Math.number_or_decimal(), atom(), Cldr.backend()) ::
  {:ok, binary()} | {:error, {module(), String.t()}}

Converts a number into the representation of a non-latin number system.

This function converts numbers to a known number system only, it does not provide number formatting.

Arguments

• number is a float, integer or Decimal

• system_name is any number system name returned by Cldr.known_number_systems/0 or a number system type returned by Cldr.known_number_system_types/0

• backend is any Cldr backend. That is, any module that contains use Cldr

Returns

• {:ok, string_of_digits} or

• {:error, {exception, reason}}

Notes

There are two types of number systems in CLDR:

• :numeric in which the number system defines a direct mapping between the latin digits 0..9 into a the number system equivalent. In this case, to_system/3 invokes Cldr.Number.Transliterate.transliterate_digits/3 for the given number.

• :algorithmic in which the number system does not have the same structure as the :latn number system and therefore the conversion is done algorithmically. For CLDR the algorithm is implemented through Cldr.Rbnf rulesets. These rulesets are considered by CLDR to be less rigorous than the :numeric number systems and caution and testing for a specific use case is recommended.

Examples

iex> Cldr.Number.System.to_system 123456, :hebr, TestBackend.Cldr
{:ok, "קכ״ג׳תנ״ו"}

iex> Cldr.Number.System.to_system 123, :hans, TestBackend.Cldr
{:ok, "一百二十三"}

iex> Cldr.Number.System.to_system 123, :hant, TestBackend.Cldr
{:ok, "一百二十三"}

iex> Cldr.Number.System.to_system 123, :hansfin, TestBackend.Cldr
{:ok, "壹佰贰拾叁"}

@spec to_system!(Cldr.Math.number_or_decimal(), atom(), Cldr.backend()) ::
  binary() | no_return()

Converts a number into the representation of a non-latin number system. Returns a converted string or raises on error.

Arguments

• number is a float, integer or Decimal

• system_name is any number system name returned by Cldr.known_number_systems/0 or a number system type returned by Cldr.known_number_system_types/0

• backend is any Cldr backend. That is, any module that contains use Cldr

Returns

• string_of_digits or

• raises an exception

See Cldr.Number.System.to_system/3 for further information.

Examples

iex> Cldr.Number.System.to_system! 123, :hans, TestBackend.Cldr
"一百二十三"

iex> Cldr.Number.System.to_system! 123, :hant, TestBackend.Cldr
"一百二十三"

iex> Cldr.Number.System.to_system! 123, :hansfin, TestBackend.Cldr
"壹佰贰拾叁"

Returns an error tuple for an number system unknown to a given locale.

Arguments

• number_system is any number system name not returned by Cldr.known_number_systems/0

• locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag struct returned by Cldr.Locale.new!/2

• valid_number_systems is a map returned by Cldr.Number.System.number_systems_for/2