$ dart run intl_translation:generate_from_arb \
    --output-dir=lib/l10n --no-use-deferred-loading \
    lib/main.dart \
    lib/l10n/intl_en.arb lib/l10n/intl_fr.arb lib/l10n/intl_messages.arb
    

    The DemoLocalizations class uses the generated initializeMessages()
function (defined in intl_messages_all.dart)
to load the localized messages and Intl.message() to look them up.