i18n-tag-wrapper

A wrapper to es2015-i18n-tag for use with Next.js

Usage

import translatorSetup from 'i18n-tag-wrapper'
import fr from './locales/fr'
import de from './locales/de'

const locales = { fr, de }
const default = fr

const getTranslator = translatorSetup({ default, plurals })

const T = getTranslator("fr")

let name = "Henri"

T`Hello ${name)}`
// Bonjour Henri

Locale configuration files

Example:

{
  locales: 'de-DE',
  // group: 'my-lib', // Optional, can be used to avoid configuration overrides. This is recommended for libraries!
  translations: {
      'Hello ${0}': 'Hallo, ${0}',
      'You have ${0} notifications:none': 'Sie habe keine Mitteilung',
      'You have ${0} notifications:one': 'Sie habe eine Mitteilung',
      'You have ${0} notifications:few': 'Sie habe zwei Mitteilungen',
      'You have ${0} notifications:many': 'Sie habe ${0} Mitteilungen',
      'You have ${0} horses:none': 'Sie haben kein Pferd',
      'You have ${0} horses:one': 'Sie haben ein Pferd',
      'You have ${0} horses:zwei': 'Sie haben zwei Pferde',
      'You have ${0} horses:many': 'Sie haben ${0} Pfrede',
  },
  number: {
      currency: 'EUR' // Intl NumberFormat options as described here: https://goo.gl/pDwbG2
  },
  date: {
      [...options] // Intl DateTimeFormat options as described here: https://goo.gl/lslekB
  },
  /**
   * @param {number} n Number of things
   * @returns {'none'|'one'|'few'|'many'|'other'}
   */
  plurals: (n) => {
    return n == 0 ?
      'none'
    : n == 1 ?
      'one'
    : n == 2 ?
      'few'
    : 'many'
  }
}

Plurals

Locale files must export a plurals(n) function with the following signature:

type Purals = (n: integer) -> "none"|"one"|"few"|"many"|"other"

Depending on the pluralization rules for your language, plurals() may return not return all variants. English, for instance only requires "one" and "many", but Polish will require all of them.

In the translations (under the translations key in the locale file), each translation requiring plural handling should have as many keys as there are variants returned by the plurals() function. Each key should by appended with the variant it handles.

Long sentences are no match for good examples:

// /locale/de.js
{
  locales: 'de-DE',
  /*
   * Germans like to write 0 as kein(e), 1 as ein(e), and 2 as zwei, using
   * numbers for higher values.
   */
  plurals: (n) => {
    return n == 0 ?
      'none'
    : n == 1 ?
      'one'
    : n == 2 ?
      'few'
    : 'many'
  }
  translations: {
    'Hello ${0}': 'Hallo, ${0}',
    /*
      * Plurals returns 4 possible variants, either: none, one, few or many
      * The "You have ${0} notifications" must have 4 variants
      */
    'You have ${0} notifications:none': 'Sie habe keine Mitteilung',
    'You have ${0} notifications:one': 'Sie habe eine Mitteilung',
    'You have ${0} notifications:few': 'Sie habe zwei Mitteilungen',
    'You have ${0} notifications:many': 'Sie habe ${0} Mitteilungen',
  }
}

Using it:

T.some(0, 'You have ${0} notifications')
// Sie habe keine Mitteilung

T.some(1, 'You have ${0} notifications')
// Sie habe eine Mitteilung

T.some(2, 'You have ${0} notifications')
// Sie habe zwei Mitteilungen

T.some(1000, 'You have ${0} notifications')
// Sie habe 1,000 Mitteilungen