Cldr.Rbnf.for_locale-exclamation-mark

You're seeing just the function for_locale-exclamation-mark, go back to Cldr.Rbnf module for more information.

for_locale!(locale)

Returns rbnf_rules for a locale or raises an exception if there are no rules.

locale is any Cldr.LanguageTag
backend is any module that includes use Cldr and therefore is a Cldr backend module

for_locale!(locale, backend)

Returns rbnf_rules for a locale and backend or raises an exception if there are no rules.

locale is any locale name returned by Cldr.Rbnf.known_locale_names/1
backend is any module that includes use Cldr and therefore is a Cldr backend module