How to do localization with Javascript

  LOCALIZATION.WARNING: 'Achtung vor dem %s, er ist gefährlich !'

  alert(translate(LOCALIZATION.WARNING, "Zauberer"));

  // Example
  var LOCALIZATION = {
    LANGUAGE: 'GERMAN',
    WARNING: 'Achtung vor dem %s, er ist gefährlich !',
    LOADING: 'Bitte warten, Daten werden geladen',
    WELCOME: 'Hallo %s, wie geht\'s dir ?'
  };

                
  (function () {
    if (!window.translate) {
      /** 
       * this global function is for string substitution
       * @property {string} string to translate.
       * @property {string} as much 
       * return STRING
       */         
      window.translate = function(){
        var html = [ ];
        var arguments = arguments;
        var string = arguments[0];

        var objIndex = 0;
        var reg = /%s/;
        var parts = [ ];

        /** 
         * analyze the string, extract the parts with the %s identifier.
         */               
        for ( var m = reg.exec(string); m; m = reg.exec(string) ) {  
          // m[0][0] gives undefined in IE
          parts.push(string.substr(0, m[0][0] === "%" ? m.index : m.index));
          parts.push("%s");
          string = string.substr( m.index+m[0].length );
        }
        parts.push(string);

        /** 
         * analyze the parts, replace the %s with the given arguments. 
         * beware of undefined!
         */               
        for (var i = 0; i < parts.length; ++i){
            var part = parts[i];
            if (part && part == "%s"){
              var object = arguments[++objIndex];
              if (object == undefined) {
                html.push("%s");
              }else{
                html.push(object);
              };
            }else{
              html.push(part);
            }            
        }

        /** 
         * Join the array and return as string.
         */
        return html.join('');
      }
    };
  })();