Function: t()

function t<K>(
   locale, 
   key, 
params?): Locale<K>

Formats a localized message by key with strongly-typed params inferred from your MF2 message.

• Supports LocaleLike: pass a locale string ('en-US') or any object with { locale } or { guildLocale }.
• Accepts nested params (e.g., { user: { name: 'Robo' } }) which are auto-flattened to dotted paths.
• Handles MF2 number/date/time (e.g., {$n :number}, {$ts :time}, {$ts :date}); for date/time the param can be Date | number.

🔑 About namespaced keys

Keys are namespaced by file path:

• /locales/<locale>/common.json ⇒ common:<json-key>
• /locales/<locale>/shared/common.json ⇒ shared/common:<json-key>
• Deeper folders keep slash-separated segments (e.g., shared/common/example:<json-key>). The key argument must be the full namespaced key and is type-safe via LocaleKey.

Type Parameters

Type Parameter	Description
K extends LocaleKey	A key from your generated LocaleKey union (namespaced).

Parameters

Parameter	Type	Description
locale	any	A LocaleLike ('en-US', { locale: 'en-US' }, or a Discord Interaction/guild context).
key	K	A namespaced key present in your /locales folder (e.g., common:hello.user).
params?	any	Parameters inferred from the MF2 message (ParamsFor<K>). Nested objects are allowed.

Returns

Locale<K>

The formatted string for the given locale and key.

Examples

// /locales/en-US/common.json:
// { "hello.user": "Hello {$user.name}!" }
// Namespaced key becomes: "common:hello.user"

import { t } from '@robojs/i18n'
t('en-US', 'common:hello.user', { user: { name: 'Robo' } }) // "Hello Robo!"

// MF2 plural-style match (file: /locales/en-US/stats.json):
// { "pets.count": ".input {$count :number}\n.match $count\n  one {{You have {$count} pet}}\n  *   {{You have {$count} pets}}" }
t('en-US', 'stats:pets.count', { count: 1 }) // "You have 1 pet"
t('en-US', 'stats:pets.count', { count: 3 }) // "You have 3 pets"

// Date/time (file: /locales/en-US/common.json):
// { "when.run": "Ran at {$ts :time style=short} on {$ts :date style=medium}" }
t('en-US', 'common:when.run', { ts: Date.now() })

// Using a Discord interaction object (has {locale} or {guildLocale}):
export default (interaction: ChatInputCommandInteraction) => {
  return t(interaction, 'common:hello.user', { user: { name: interaction.user.username } })
}

Throws

If the locale is unknown (no /locales/<locale> loaded) or the key is missing in that locale.

Remarks

• You can also pass dotted params directly: t('en-US', 'common:hello.user', { 'user.name': 'Robo' }).
• If different locales disagree on a param’s kind, the generator safely widens the param type.