phpjs/workbench/gettext/ngettext.js

php.js offers community built php functions in javascript

function ngettext(msgid1, msgid2, n) {
  // http://kevin.vanzonneveld.net
  // +   original by: Brett Zamir (http://brett-zamir.me)
  // -    depends on: setlocale
  // *     example 1:
  // *     returns 1:

  // BEGIN REDUNDANT
  this.php_js = this.php_js || {};
  // END REDUNDANT

  var lang = this.setlocale('LC_ALL', 0);

  var domain = this.php_js.current_textdomain;

  // rely on phpjs.locales.LL.nplurals(n)

}