Internationalization

Summary

Neura localizes its own interface strings, the ~14 texts the components render themselves: the date picker's footer buttons and aria-labels, dismiss/loading labels, empty-state defaults. Month names, weekday names, and the first day of the week come from the browser's Intl data, so every language works there without a translation file. 42 locale packs ship built in: every EU official language, the Nordics, and the most-used world languages (see the list below); anything else registers a ~14-key pack.

Application text is deliberately out of scope: on server-rendered pages that belongs to the server's own resource bundles. The date input format also stays ISO (YYYY-MM-DD): it's a data contract, not a display string.

Locale selection

Source	Notes
`Neura.i18n({ locale: 'cs' })`	Explicit: wins over everything. Set it before components render; existing DOM is not re-rendered.
`<html lang="cs">`	The normal server-rendered path: the server sets one attribute and Neura follows.
(neither)	English.

Locale codes are case-insensitive, and regional codes fall back to their base language: cs-CZ uses the cs pack (an exact regional pack, if registered, wins). Neura.i18n({ locale: null }) clears an explicit locale and returns to <html lang> detection.

Examples

Switch locale, then open the date picker or spawn a flag; new components render in the chosen language:

Note what the flag demo shows: its title and body are application content: the demo script translates them itself, keyed off Neura.i18n().locale, exactly as a real app would. The only flag string Neura itself localizes is the close button's aria-label ("Dismiss" / "Zavřít"; inspect the × to see it).

JavaScript API

Neura.i18n({ locale: 'cs' });          // switch locale (before rendering)
Neura.i18n();                          // → { locale, messages }
Neura.i18n({ messages: { today: 'Nyní' } });   // override single keys
Neura.i18n.locales();                  // → the built-in locale codes

// Add a language - partial packs fall back to English per key:
Neura.i18n.register('de', {
  today: 'Heute', clear: 'Löschen', dismiss: 'Schließen',
  chooseDate: 'Datum wählen', prevMonth: 'Voriger Monat',
  nextMonth: 'Nächster Monat', hour: 'Stunde', minute: 'Minute',
  clearSelection: 'Auswahl löschen', searchOptions: 'Optionen durchsuchen',
  noMatches: 'Keine Treffer', noEntries: 'Keine Einträge',
  loading: 'Laden', resizeSidebar: 'Seitenleiste anpassen',
});
Neura.i18n({ locale: 'de' });

Built-in locales

en (fallback catalog) plus 42 packs (every EU official language, the Nordics, and the most-used world languages): ar Arabic · bg Bulgarian · bn Bengali · cs Czech · da Danish · de German · el Greek · es Spanish · et Estonian · fa Persian · fi Finnish · fr French · ga Irish · he Hebrew · hi Hindi · hr Croatian · hu Hungarian · id Indonesian · is Icelandic · it Italian · ja Japanese · ko Korean · lt Lithuanian · lv Latvian · mt Maltese · nb Norwegian Bokmål (also no) · nl Dutch · pl Polish · pt Portuguese · ro Romanian · ru Russian · sk Slovak · sl Slovenian · sr Serbian (Cyrillic) · sv Swedish · th Thai · tr Turkish · uk Ukrainian · ur Urdu · vi Vietnamese · zh Chinese (Simplified) · zh-Hant Chinese (Traditional, also zh-TW/zh-HK/zh-MO)

One caveat: the packs are machine-translated standard UI vocabulary awaiting native-speaker review. Serbian ships in Cyrillic; register a sr-Latn pack if you prefer latinica.

Right-to-left (RTL) layout

Neura fully supports RTL: set dir="rtl" on <html> (or any subtree) and everything mirrors: layout and components (CSS logical properties), popover alignment, drag directions, and keyboard semantics (horizontal arrows follow visual direction in tabs and the date-picker grid, per ARIA practice). Combined with the ar, fa, he, and ur packs, those languages are supported end to end. Try it live: the RTL button in the top bar flips this whole docs site.

String catalog

Key	English	Czech (built in)	Used by
`today`	Today	Dnes	date picker
`clear`	Clear	Vymazat	date picker
`chooseDate`	Choose date	Vyberte datum	date picker (aria)
`prevMonth` / `nextMonth`	Previous/Next month	Předchozí/Další měsíc	date picker (aria)
`hour` / `minute`	Hour / Minute	Hodina / Minuta	date picker (aria)
`dismiss`	Dismiss	Zavřít	flags, banners (aria)
`loading`	Loading	Načítání	spinner (aria), RESTful table
`clearSelection`	Clear selection	Vymazat výběr	select (aria)
`searchOptions`	Search options	Hledat možnosti	select (aria)
`noMatches`	No matches	Žádné shody	select
`noEntries`	No entries	Žádné záznamy	RESTful table
`resizeSidebar`	Resize sidebar	Změnit šířku panelu	sidebar (aria)

What Intl covers automatically

For the active locale the date picker derives month names, short weekday names, and the first day of the week from Intl.DateTimeFormat / Intl.Locale (no dictionary involved). A per-instance Neura.datePicker(input, {locale}) option still overrides the global locale where needed.

Easter eggs 🖖

To prove Neura.i18n.register() handles anything with a BCP-47 code, this page registers three extra locales: Klingon (tlh, a real ISO 639-2 code; vocabulary after Okrand) and Sumerian (sux, reconstructed from attested roots; the previous/next month labels honor the Sumerian conception that the past lies before you, igi, and the future behind, egir), and Hobbitish (x-hobbit: Westron has no ISO code, so it demonstrates a private-use BCP-47 tag; and since Tolkien rendered Westron as English, the pack is proper Shire-speech). Pick them in the locale dropdown above. None of them ship in the library bundle, and Intl has no calendar data for them, so month names fall back - exactly the graceful degradation a custom locale gets. The Shire Reckoning (Afteryule, Solmath, Rethe…) must wait for a custom-month-names date-picker option.

AUI compatibility

Independent of AJS.I18n: the shim's AJS.I18n.getText continues to serve legacy consumer code with its own keys; Neura.i18n is only about Neura's built-in strings. No aui-* surface involved.