ISO 639 language code of language. Prefers shortest possible version.
$fallback
$fallback
Fallback language code.
$messages
$messages
Array of localizable messages.
$errorNames
$errorNames
Array of localizable error codes.
$error
$error
True if no message file was found for this language, so English
is being used instead. Check this if you'd like to notify the
user that they've used a non-supported language.