HTTP protocol logic in javascript

gistfile1.js

// Stupid as shit
var url  = (("https:"==document.location.protocol)?"https":"http") + "://domain.com/file.js";

// Better
var url  = document.location.protocol + "//domain.com/file.js";

// Best (protocol-less FTW!)
var url = "//domain.com/file.js";