20180831 匿名函数自动调用表达式

引用: https://www.runoob.com/js/js-function-definition.html

 

匿名函数自动调用表达式: (function(){})()

 

<p id="demo"></p>

<script>
(function(){document.getElementById("demo").innerHTML = "Hello World!";})()
</script>

Output: Hello World!