code: function(str, formats) {
      // first, replace any ORDERED replacements.
      var idx  = 0; // the current index for non-numerical replacements
      return str.replace(/%@([0-9]+)?/g, function(s, argIndex) {
        argIndex = (argIndex) ? parseInt(argIndex,0) - 1 : idx++ ;
        s = formats[argIndex];
        return ((s === null) ? '(null)' : (s === undefined) ? '' : s).toString();
      }) ;
    }
docs: Apply formatting options to the string. This will look for occurrences
  of "%@" in your string and substitute them with the arguments you pass into
  this method. If you want to control the specific order of replacement,
  you can add a number after the key as well to indicate which argument
  you want to insert.
  
  Ordered insertions are most useful when building loc strings where values
  you need to insert may appear in different orders.
  
  ```javascript
  "Hello %@ %@".fmt('John', 'Doe');     // "Hello John Doe"
  "Hello %@2, %@1".fmt('John', 'Doe');  // "Hello Doe, John"
  ```
  
  @method fmt
  @param {Object...} [args]
  @return {String} formatted string