l10n.js

l10n.js
=======

l10n.js is a JavaScript library that enables passive localization through native
JavaScript methods, gracefully degrading if the library is not present. You can make
Ajax applications, JavaScript libraries, etc. that can be localized but not require
l10n.js to function. There is already a placeholder method for all API calls
as specified in the ECMAScript specification and is present in all JavaScript
engines, so when l10n.js isn't present, your application works fine.


Demo
----

You can try out the [online demo][1] to see l10n.js in action.

Currently the demo supports the following locales.

* English
* American English
* British English
* Canadian English
* Australian English
* Portuguese
* Spanish
* French
* Dutch
* German
* Finnish
* Vietnamese
* Italian
* Norwegian
* Russian
* Lojban
* Danish
* Hebrew
* Bulgarian
* Simplified Chinese
* Swedish
* Turkish
* Hungarian
* Czech
* Catalan
* Japanese

If you know a language that isn't currently supported in the demo, I encourage you to
contribute a localization by sending me your own localizations, either [through GitHub][2]
or [directly][3]. The following strings would need to be localized:

* %title to {Locale} - l10n.js demo in the locale.
* %info to You are viewing a {locale} localization
of this page. in the locale.
* Optionally, %locale.dir to rtl if the locale uses right-to-left directionality.


Supported Browsers
------------------

* Internet Explorer 5+
* Firefox 2+
* Opera 9+
* Doesn't support region-specific locales. Only gives "en" in the case of "en-US".
* Google Chrome 1+
* Safari 4+


Getting Started
---------------

1. [Download l10n.js][4].
2. Localize strings used in your JavaScript application. See the [demo localizations
file][5] for an example localizations file. You can also specify external
localizations in your main localizations file by assigning a URL string to a language
code, such as "en-us": "localizations/en-us.json".
3. Include the appropriate link elements, as described in the usage section, anywhere in
your document. I recommend putting it in the document's .
4. Place
anywhere after the tag.
5. Call toLocaleString() on any strings you wish to localize.


Usage
-----

$3

Calling toLocaleString() on every localizable string can create a lot of extra typing
and bloat for sending your JavaScript down the wire. I recommend using the following
helper function to localize strings. The reason I don't define this in l10n.js is to not
introduce any new globals, which keeps l10n.js a one of the JavaScript libraries
least-prone to conflicts with other libraries.

var l = function (string) {
return string.toLocaleString();
};

With this helper function, you can start writing l("Your localizable string") instead
of "Your localizable string".toLocaleString(). I chose l instead of _ (an
underscore), because it's easier to spot so you can quickly skim your code to see which
strings are localizable.

$3

If you don't mind requiring l10n.js for your JavaScript application or library to
function, I suggest using short variable strings instead of default strings. It saves
bandwidth by decreasing the size of localization files, and it enables you to write
nice, short code as such in the following.

* document.title = l("%title.search")
* Example results: "Seach - Acme, Inc."
* confirm(l("%confirm.deleteAccount"))
* Example results: "Are you sure you want to delete your account?"
* link.href = "http://www.google." + l("%locale.tld")
* Example results: "http://www.google.co.uk"

Often, string concatenation is used instead of replacement in JavaScript. With l10n.js,
to make localization easier, you may have to use replacements instead. You might want to
use a JavaScript library that implements something similar to C++'s sprintf(). A nice
JavaScript implementation I'd recommend is [php.js's sprintf()][6].

$3

If you are using single localization URLs
(),
they will only be downloaded when needed. If you are using multiple localizations in one
(), then the file
will be downloaded right away, but externally linked localizations in the localization
file will not be. If you provide an interface for your users to change locales, any
non-loaded localization files will be loaded when necessary.

$3

Multiple localizations can be included with one localization JSON file, with all of the
top properties being language codes. Instead of putting all of the localized strings
directly in the file, you may want to assign a specifc localization JSON URL to each
locale, as to save bandwidth by only downloading locales the user needs.

The following is an example localization file for
.

{
"en-US": {
"What is your favourite colour?": "What is your favorite color?"
},
"fr": "path/to/french-localization.json"
}

Using localization files is the same as calling String.toLocaleString() witht the JSON
localizations object as the first parameter.

You can also include single localizations by specifying the standard HTML5 hreflang link
element attribute and using a rel of localization instead of localizations with an
's', as shown in the following.



The JSON file for the localization might look like the following.

{
"What is your favourite colour?": "What is your favorite color?"
}


API
---

Strong and emphasized text has titles (which can be viewed by hovering your cursor over
them) containing their type if they are not functions or return type if they are.

$3

String.toLocaleString([localizations])

If localizations is an object, it is added to the
localizations.


If localizations is a string, it is requested as JSON and
then added to the localizations.


If localizations is false, then all
localizations are reset.


If localizations is an object, and a locale is
false, then all localizations for that locale are reset.

The string representation of the String contructor is returned, to
maintain backwards compatibility with any code using this method to actually get it.

Examples

• 
  Loading a localizations JSON file:
  

  String.toLocaleString("path/to/localizations.json")

  
  


• 
  Defining localizations directly:
  

  
  The nearest locale to the user's locale that has the string being localized is
  used in localization.
  

  
  

  String.toLocaleString({
  
      "es": { // Spanish
  
          "Hello, world!": "¡Hola, mundo!"
  
          // more localizations...
  
      },
  
      "en-US": { // American English
  
          "Hello, world!": "Hello, America!" // Locale-specific message
  
          // more localizations...
  
      },
  
      "en-GB": false, // resetting British English localizations
  
      // Specifying external localization JSON for Japanese:
  
      // The URL isn't requested unless the user's locale is Japanese
  
      "ja": "localizations/ja.json"
  
  })

  
  


• 
  Resetting all localizations:
  

  String.toLocaleString(false)

  
  

aString.toLocaleString()

Returns the localized version of aString in the user's locale,
if available. Otherwise, it returns the same string.

$3

String.locale

A configurable string which represents the language code of the locale to use for
localization. It defaults to the user's own locale.

String.defaultLocale

A configurable string which represents the language code of the default locale to
use for localization if no localizations are available in the user's locale. By
default this is not configured, and may be ignored if you are using l10n.js for
passive-only localizations.

!Tracking image

[1]: http://purl.eligrey.com/l10n.js/demo
[2]: https://github.com/eligrey/l10n.js/edit/master/demo/localizations.js
[3]: http://purl.eligrey.com/contact
[4]: http://purl.eligrey.com/github/l10n.js/raw/master/l10n.js
[5]: http://purl.eligrey.com/github/l10n.js/blob/master/demo/localizations.js
[6]: http://phpjs.org/functions/sprintf