Locale for Javascript

Features

• Multiple target languages (translate to)
• Any base language (translate from)
• Plural forms for any language
• Simultaneous support of multiple languages
• Flexible placeholders
• Remote translation

It's simple

// Translate
var who = 'world';
__('Hello, %s!', who);

// Translate plural
__([
  'There is %n item in your cart (total $%s).',
  'There are %n items in your cart (total $%s).'
  ], cart.items.length, cart.total
);

Installation

Install node.js library:

npm install locale-js

or download minified library i18n.min.js (for browser apps).

Tools

See locale-tools project.

API

• Library import
• Configuration
• Creating i18n object
• Translation target
• Translation
• Strings format
• Remote translation

Library import

For node.js:

var locale = require('locale-js');

For browser:

<script type="text/javascript" src="i18n.min.js"></script>

Configuration

Library initialization (browser):

locale.init(base, rule)

, where:

• base (string) - id of application's base language;
• rule (string) - plural rule for base language.

You should use locale.add() to add translation for each used language.

Library initialization (node.js):

locale.init(path)

, where path is the path to the translation files.

This function searches for and loads all translations automatically.

Example:

// In browser:
locale.init('ru', '(n%10==1 && n%100!=11 ? 0 : n%10>=2 && n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2)');
// You can skip parameters if your base language is English
locale.init();
// In node.js app:
locale.init('./i18n/');

Add translation:

locale.add(lang, translation)

, where:

• lang (string) - language id;
• translation (object) - translation JSON.

Creating i18n object

Create translation object for the given target:

new locale.i18n(target)

, where target (string or null) - 1) id of the target language, 2) empty string or 3) null.

Sets target language to base language if target is '' (empty string).
Enables remote translation mode if target is null.

Example:

// Create translation object for Russian language
var i18n = new locale.i18n('ru');
// Create translation object for base language (no translation)
var i18n = new locale.i18n('');
// Create translation object for remote translation
var i18n = new locale.i18n(null);
// And pull up __() function to the local scope
var __ = i18n.__;

Translation target

This methods are accessible for locale and i18n objects.

Get current target:

to()

Returns (string or null) current translation target.

Set target:

to(target)

, where target (string or null) - 1) id of target language, 2) empty string or 3) null.

Sets target language to base language if target is '' (empty string).
Switches i18n object to remote translation mode if target is null.

Example:

// Set target language for library to German
locale.to('de');
// Create i18n object and set its target language to Russian
var i18n = new locale.i18n();
i18n.to('ru');
// Enable remote translation mode
i18n.to(null);

Translation

This methods are accessible for locale and i18n objects.

For simple form:

__(phrase)
__(phrase, ...)
__(phrase, array)
__(phrase, object)

, where:

• phrase (string) - string for translation (can contains placeholders);
• ... (mixed) - any number of additional args;
• array (Array) - array of args;
• object (object) - map of args.

Returns translated string or remote translation data (in case of remote translation target).

For plural form:

__(phrase, n)
__(phrase, n, ...)
__(phrase, n, array)
__(phrase, n, object)

, where:

• phrase (array) - array of strings each of them is a plural form for translation (can contains placeholders);
• n (numeric) - base number of plural form;
• ... (mixed) - any number of additional args;
• array (Array) - array of args;
• object (object) - map of args.

Returns translated string or remote translation data (in case of remote translation target).

Example:

// Simple:

// Hello!
__('Hello!');
// Hello, anonymous!
__('Hello, %s!', 'anonymous');
// Hello, John Smith!
__('Hello, %s(2) %s(1)!', [ 'Smith', 'John' ]);
// Hello, Foo (bar)!
__('Hello, %s(name) (%s(login))!', { name: 'Foo', login: 'bar' });

// Plural:

// Inbox: 1 unreaded message.
__([ 'Inbox: %n unreaded message.', 'Inbox: %n unreaded messages.' ], 1);
// Inbox: 7 unreaded messages.
__([ '%s(1): %n unreaded message.', '%s(1): %n unreaded messages.' ], 7, 'Inbox');
// Anonymous, you have 365 unreaded messages in the "Spam" folder.
__([
    '%s(1), you have %n unreaded message in the "%s(2)" folder.',
    '%s(1), you have %n unreaded messages in the "%s(2)" folder.'
   ], 365, [ 'Anonymous', 'Spam' ]);
// The second way
__([
    '%s(login), you have %n unreaded message in the "%s(folder)" folder.',
    '%s(login), you have %n unreaded messages in the "%s(folder)" folder.'
   ], 365, { login: 'Anonymous', folder: 'Spam' });

// Remote:

// { __i18n: true, phrase: 'Hello!', n: undefined, args: {} }
__('Hello!');

See also: Remote translation.

Strings format

Phrase, id and comment

Each string consists of phrase, id and comment. Both id and comment are optional, id separates from phrase by '#' sign, comment separates from id by space.

<phrase>[#<id>[ <comment>]]

phrase + id is unique key for translation dictionary. You can create several variants of translation of the same phrase using different ids.

Also you can place any useful info for translator to comment.

Example:

// No id, no comment
__('Hello!');
// Both id and comment
__('Hello!#another This is a comment for translator');
// Only id
__('Hello!#another');
// Only comment
__('Hello!# This is a comment for translator');

Placeholders

Phrases can contains placeholders.

Placeholder's format is:

%s - fills with the next arg.
%s(id) - fills with the id arg (arg number id for additional args or arg[id] for array and map args).
%n - fills with base number of plural form (valid for plural form only).

Example:

See example of __() function.

Special characters

Special characters are '#' and '%'. If you need it in your string you should type it twice.

// 40%
__('%s%%', 40);
// It's # not a comment!
__('It\'s ## not a comment!);

Also you can use '(' character after placeholder. Type it twice too:

// Order by name(asc)
__('Order by %s((asc)', 'name');

Remote translation

Search for remote translation data in the obj and replace it by translated string:

i18n.tr(obj)

, where obj (object) - object for translation.

Remote translation data structure:

{
  __i18n: true,
  phrase: <phrase>,
  n: <number>,
  args: <arguments>
}

See also: Creating i18n object.

Example:

// Server:

// Create i18n object for the remote mode
var i18n = new locale.i18n(null);
var __ = i18n.__;
submit({
  id: 832367,
  errno: 404,
  error: __('Path not found!')
});

// Client:

var i18n = new locale.i18n('ru');
var msg = receive();
i18n.tr(msg);
/*

  {
    id: 832367,
    errno: 404,
    error: 'Путь не найден!'
  }

*/