shorten function

shorten.js

// ==================== Existing =========================================

shorten: function(url, callback, reshortenLink) {
  // ...
},

// called
Shortener.shorten('site.com/some/url', function(){
  // more logic
}, true)

// ==================== Alertnate =========================================

// Potentially currying the functions so the last arg is always the callback
// reshortenLink is an optional param
shorten: function(url, reshortenLink, callback) {
  if (typeof reshortenLink === 'function'){
    callback = reshortenLink;
    reshortenLink = null;
  }
  // ...
},

// called
Shortener.shorten('site.com/some/url', function(){
  // more logic
})
// or
Shortener.shorten('site.com/some/url', true, function(){
  // more logic
})