I18n Dreamhost

This lib enables translations, exposing three public methods:

• .translate()
• .moment()
• .numberFormat()

Translate Method

translate() accepts up to three arguments (string, string, object), depending on the translation needs. The second and/or third parameter can be omitted:

/**
 * @param {string} original  - the string to translate, will be used as single version if plural passed
 * @param {string} [plural]  - the plural string to translate (if applicable)
 * @param {object} [options] - properties describing translation requirements for given text
 **/

Options

The following attributes can be set in the options object to alter the translation type. The attributes can be combined as needed for a particular case.

• options.args [string, array, or object] arguments you would pass into sprintf to be run against the text for string substitution. See docs
• options.components [object] markup must be added as React components and not with string substitution. See mixing strings and markup.
• options.comment [string] comment that will be shown to the translator for anything that may need to be explained about the translation.
• options.context [string] provides the ability for the translator to provide a different translation for the same text in two locations (dependent on context). Usually context should only be used after a string has been discovered to require different translations. If you want to provide help on how to translate (which is highly appreciated!), please use a comment.

Usage

If you pass a single string into translate, it will trigger a simple translation without any context, pluralization, sprintf arguments, or comments. You would call it like this.

var i18n = require( 'i18n' );
var translation = i18n.translate( 'Some content to translate' );

Strings Only

Translation strings are extracted from our codebase through a process of static analysis and imported into GlotPress where they are translated (more on that process here). So you must avoid passing a variable, ternary expression, function call, or other form of logic in place of a string value to the translate method. The one exception is that you can split a long string into mulitple substrings concatenated with the + operator.

/*----------------- Bad Examples -----------------*/
 
// don't pass a logical expression argument
const translation = i18n.translate( condition ? 'foo' : 'bar' );
 
// don't pass a variable argument
const translation = i18n.translate( foo );
 
// don't pass a function call argument
const translation = i18n.translate( foo( 'bar' ) );
 
/*----------------- Good Examples -----------------*/
 
// do pass a string argument
const example = i18n.translate( 'foo' );
 
// do concatenate long strings with the + operator
const translation = i18n.translate(
    `I am the very model of a modern Major-General,
    I've information vegetable, animal, and mineral,
    I know the kings of England, and I quote the fights historical
    from Marathon to Waterloo, in order categorical.`
);

String Substitution

The translate() method uses sprintf interpolation for string substitution (see docs for syntax details). The option.args value is used to inject variable content into the string.

// named arguments (preferred approach)
i18n.translate( 'My %(thing)s has %(number)d corners', {
    args: {
        thing: 'hat',
        number: 3
    }
} );
// 'My hat has 3 corners'
 
// argument array
i18n.translate( 'My %s has %d corners', {
    args: [ 'hat', 3 ]
} );
// 'My hat has 3 corners'
 
// single substitution
i18n.translate( 'My %s has 3 corners', {
    args: 'hat'
} );
// 'My hat has 3 corners'

Pluralization

You must specify both the singular and plural variants of a string when it contains plurals. If the string uses placeholders that will be replaced with actual values, then both the plural and singular strings should include those placeholders. It might seem redundant, but it is necessary for languages where a singular version may be used for counts other than 1.

 
// An example where the translated string does not have
// a number represented directly, but still depends on it
var numHats = howManyHats(), // returns integer
    content = i18n.translate(
    	'My hat has three corners.',
    	'My hats have three corners.',
    	{
            count: numHats
        }
    );
 
// An example where the translated string includes the actual number it depends on
var numDays = daysUntilExpiration(), // returns integer
    content = i18n.translate(
        'Your subscription will expire in %(numberOfDays)d day.',
        'Your subscription will expire in %(numberOfDays)d days.',
        {
            count: numDays,
            args: {
                numberOfDays: numDays
            }
        }
    );
 

More translate() Examples

// simplest case... just a translation, no special options
var content = i18n.translate( 'My hat has three corners.' );
 
// sprintf-style string substitution
var city = getCity(), // returns string
    zip = getZip(), // returns string
    content = i18n.translate( 'Your city is %(city)s, your zip is %(zip)s.', {
        args: {
            city: city,
            zip: zip
        }
    } );
 
// add a comment to the translator
var content = i18n.translate( 'g:i:s a', {
        comment: 'draft saved date format, see http://php.net/date'
    } );
 
// providing context
var content = i18n.translate( 'post', {
        context: 'verb'
    } );
 

Moment Method

This module includes an instantiation of moment.js to allow for internationalization of dates and times. We generate a momentjs locale file as part of loading a locale and automatically update the moment instance to use the correct locale and translations. You can use moment() from within any component like this:

var thisMagicMoment = i18n.moment( "2014-07-18T14:59:09-07:00" ).format( 'LLLL' );

And you can use it from outside of React like this.

var i18n = require( 'i18n' );
var thisMagicMoment = i18n.moment( "2014-07-18T14:59:09-07:00" ).format( 'LLLL' );

numberFormat Method

The numberFormat method is also available to format numbers using the loaded locale settings (i.e., locale-specific thousands and decimal separators). You pass in the number (integer or float) and (optionally) the number of decimal places you want (or an options object), and a string is returned with the proper formatting for the currently-loaded locale. You can also override the locale settings for a particular number if necessary by expanding the second argument into an object with the attributes you want to override.

Examples

// These examples assume a 'de' (German) locale to demonstrate
// locale-formatted numbers
i18n.numberFormat( 2500.25 ); // '2.500'
i18n.numberFormat( 2500.1, 2 ); // '2.500,10'
i18n.numberFormat( 2500.33, { decimals: 3, thousandsSep: '*', decPoint: '@'} ); // '2*500@330'

Some Background

I18n accepts a language-specific locale json file that contains the whitelisted translation strings for your JS project, uses that data to instantiate a Jed instance, and exposes a single translate method with sugared syntax for interacting with Jed.