An Ecto.Type storing a locale as its BCP 47 string in a text column.

A Localize.LanguageTag.t/0 is a rich struct — resolved likely subtags, -u- extension keywords, a canonical form — but all of it is derived from the language tag string, so the string is what is stored. The column is ordinary text holding a canonical tag such as "en-US" or "de-DE-u-co-phonebk".

Values load back into a fully resolved Localize.LanguageTag.t/0 via Localize.validate_locale/1, so a loaded locale is canonicalized, has its -u- extensions populated and its likely subtags resolved — the same value Localize.validate_locale/1 returns anywhere else, and the resolution is cached.

Schema

# in a migration
add :locale, :string

# in a schema
field :locale, Localize.LanguageTag.Ecto.Type

Casting

cast/1 accepts a Localize.LanguageTag.t/0, or any locale identifier Localize.validate_locale/1 accepts — a string ("en-US") or an atom (:"en-US"). An identifier that is not a valid locale returns an error rather than being stored.