Guards whether the given datetime has components of a date.

Guard whether the given datetime has components of both a date and a time.

Guards whether the given datetime has components of a time.

Indicates if a given map fulfills the requirements for a naive date time or date time.

Indicates if a given map fulfills the requirements for a date time.

Indicates if a given map fulfills the requirements for a naive date time.

@spec to_string(
  Cldr.Calendar.any_date_time(),
  Cldr.backend() | Keyword.t(),
  Keyword.t()
) ::
  {:ok, String.t()} | {:error, {module(), String.t()}}

Formats a DateTime according to a format string as defined in CLDR and described in TR35.

Arguments

• datetime is a DateTime.t/0 or NaiveDateTime.t/0 struct or any map that contains one or more of the keys :year, :month, :day, :hour, :minute and :second or :microsecond with optional :time_zone, :zone_abbr, :utc_offset, :std_offset and :calendar fields.

• backend is any module that includes use Cldr and therefore is a Cldr backend module. The default is Cldr.default_backend!/0.

• options is a keyword list of options for formatting.

Options

• :format is one of :short, :medium, :long, :full or a format string or any of the keys in the map returned by Cldr.DateTime.Format.date_time_formats/3. The default is :medium. See here for more information about specifying formats.

• :date_format is any one of :short, :medium, :long, :full. If defined, this option is used to format the date part of the date time. This option is only acceptable if the :format option is not specified, or is specified as either :short, :medium, :long, :full. If :date_format is not specified then the date format is defined by the :format option.

• :time_format is any one of :short, :medium, :long, :full. If defined, this option is used to format the time part of the date time. This option is only acceptable if the :format option is not specified, or is specified as either :short, :medium, :long, :full. If :time_format is not specified then the time format is defined by the :format option.

• :style is either :at or :default. When set to :at the datetime may be formatted with a localised string representing <date> at <time> if such a format exists. See Cldr.DateTime.Format.date_time_at_formats/2.

• :prefer is either :unicode (the default) or :ascii. A small number of formats have two variants - one using Unicode spaces (typically non-breaking space) and another using only ASCII whitespace. The :ascii format is primarily to support legacy use cases and is not recommended. See Cldr.DateTime.Format.date_time_available_formats/3 to see which formats have these variants.

• :locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag.t/0 struct. The default is Cldr.get_locale/0.

• :number_system a number system into which the formatted datetime digits should be transliterated.

• :era which, if set to :variant, will use a variant for the era if one is available in the requested locale. In the :en locale, for example, era: :variant will return CE instead of AD and BCE instead of BC.

• period: :variant will use a variant for the time period and flexible time period if one is available in the locale. For example, in the :en locale period: :variant will return "pm" instead of "PM".

Notes

• If the provided datetime contains only date fields, the call is delegated to Cldr.Date.to_string/2.

• If the provided datetime contains only time fields, the call is delegated to Cldr.Time.to_string/2.

Returns

• {:ok, formatted_datetime} or

• {:error, reason}

Examples

iex> {:ok, date_time} = DateTime.from_naive(~N[2000-01-01 23:59:59.0], "Etc/UTC")
iex> Cldr.DateTime.to_string(date_time)
{:ok, "Jan 1, 2000, 11:59:59 PM"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, locale: :en)
{:ok, "Jan 1, 2000, 11:59:59 PM"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, format: :long, locale: :en)
{:ok, "January 1, 2000, 11:59:59 PM UTC"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, format: :hms, locale: :en)
{:ok, "11:59:59 PM"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, format: :full, locale: :en)
{:ok, "Saturday, January 1, 2000, 11:59:59 PM GMT"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, format: :full, locale: :fr)
{:ok, "samedi 1 janvier 2000, 23:59:59 UTC"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, format: :full, style: :at, locale: :en)
{:ok, "Saturday, January 1, 2000 at 11:59:59 PM GMT"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, format: :full, style: :at, locale: :fr)
{:ok, "samedi 1 janvier 2000 à 23:59:59 UTC"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, format: :MMMMW, locale: :fr)
{:ok, "semaine 1 (janvier)"}
iex> Cldr.DateTime.to_string(date_time, MyApp.Cldr, format: :yw, locale: :fr)
{:ok, "semaine 1 de 2000"}

@spec to_string!(
  Cldr.Calendar.any_date_time(),
  Cldr.backend() | Keyword.t(),
  Keyword.t()
) ::
  String.t() | no_return()

Formats a DateTime according to a format string as defined in CLDR and described in TR35 returning a formatted string or raising on error.

Arguments

• datetime is a DateTime.t/0 or NaiveDateTime.t/0 struct or any map that contains one or more of the keys :year, :month, :day, :hour, :minute and :second or :microsecond with optional :time_zone, :zone_abbr, :utc_offset, :std_offset and :calendar fields.

• backend is any module that includes use Cldr and therefore is a Cldr backend module. The default is Cldr.default_backend!/0.

• options is a keyword list of options for formatting.

Options

• :format is one of :short, :medium, :long, :full or a format string or any of the keys returned by Cldr.DateTime.Format.date_time_formats/3. The default is :medium. See here for more information about specifying formats.

• :style is either :at or :default. When set to :at the datetime may be formatted with a localised string representing <date> at <time> if such a format exists. See Cldr.DateTime.Format.date_time_at_formats/2.

• :prefer is either :unicode (the default) or :ascii. A small number of datetime formats have two variants - one using Unicode spaces (typically non-breaking space) and another using only ASCII whitespace. The :ascii format is primarily to support legacy use cases and is not recommended. See Cldr.DateTime.Format.date_time_available_formats/2 to see which formats have these variants.

• :locale is any valid locale name returned by Cldr.known_locale_names/0 or a Cldr.LanguageTag.t/0 struct. The default is Cldr.get_locale/0.

• :number_system a number system into which the formatted datetime digits should be transliterated.

• :era which, if set to :variant, will use a variant for the era if one is available in the requested locale. In the :en locale, for example, era: :variant will return CE instead of AD and BCE instead of BC.

• period: :variant will use a variant for the time period and flexible time period if one is available in the locale. For example, in the :en locale period: :variant will return "pm" instead of "PM".

Notes

• If the provided datetime contains only date fields, the call is delegated to Cldr.Date.to_string/2.

• If the provided datetime contains only time fields, the call is delegated to Cldr.Time.to_string/2.

Returns

• formatted_datetime or

• raises an exception

Examples

iex> {:ok, date_time} = DateTime.from_naive(~N[2000-01-01 23:59:59.0], "Etc/UTC")
iex> Cldr.DateTime.to_string!(date_time, MyApp.Cldr, locale: :en)
"Jan 1, 2000, 11:59:59 PM"
iex> Cldr.DateTime.to_string!(date_time, MyApp.Cldr, format: :long, locale: :en)
"January 1, 2000, 11:59:59 PM UTC"
iex> Cldr.DateTime.to_string!(date_time, MyApp.Cldr, format: :full, locale: :en)
"Saturday, January 1, 2000, 11:59:59 PM GMT"
iex> Cldr.DateTime.to_string!(date_time, MyApp.Cldr, format: :full, locale: :fr)
"samedi 1 janvier 2000, 23:59:59 UTC"
iex> Cldr.DateTime.to_string!(date_time, MyApp.Cldr, format: :MMMMW, locale: :fr)
"semaine 1 (janvier)"
iex> Cldr.DateTime.to_string!(date_time, MyApp.Cldr, format: :yw, locale: :fr)
"semaine 1 de 2000"