Format dates acccording to the current locale

In many localization scenarios, locales can have different formats for dates. Think en vs jp, for example. Or en-US vs en-GB.

It is thus required to define different date formats for each locale, preferably even in the locale json file itself, so a person doing localization would be able to tune the formats if needed.

It’s very hard to figure out how to change date formats at all, here is a working example:

  i18n.init({
    ...
    formats: {
      date: {
        short: {month: 'numeric', day: 'numeric', year: 'numeric'}, // short seems to be the default
        full: {year: 'numeric', month: 'short', day: 'numeric'}
      }
    }
  })

However, it seems to be using exactly the same format for each different locale, maybe according to the browser’s default locale?

[kaisermann]

@rodoch Got pretty much everything right! Thanks for the great explanation 😁 It’s not hard to create a derived store from $locale to format dates with another lib:

const myDateFormatter = derived([locale], (locale) => (date) => dateLib(date, locale))

[rodoch]

I’m going to presume this isn’t the cause of your issue, but just in case: I believe svelte-i18n, at some level, wraps the Intl API. The Intl API only has access to whatever locales are available in your runtime (server-side: Node.js, client-side: whatever the browser ships with). This bit me recently working with ga-IE localisation in Ireland: Firefox and Edge ship with better localised distros here and svelte-i18n was localising the dates for me, but whenever I opened the app in Chrome the dates were displayed in English as Chrome had no support for the ga-IE locale. In the end the only solution that reliably worked in userland was to use moment.js for date formatting (manually importing ga-IE locale) and svelte-i18n for the rest of the string translation. It works good though, and the way svelte-i18n v3 has broken up the _, number and date functions so they can be tree-shaken reduces extra weight involved with adding an additional library.

Hope I haven’t got any of the above wrong @kaisermann