输出结果是什么？
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>考察js作用域、变量提升的面试题</title>
</head>
<body>
<script type="text/javascript">
var name = 'World!';
(function () {
if (typeof name === 'undefined') {
var name = 'Jack'
console.log('Goodbye ' + name)
} else {
console.log('Hello ' + name)
}
})()
</script>
</body>
</html>结果是：Goodbye Jack
