> For the complete documentation index, see [llms.txt](https://jen-hsuan-hsieh.gitbook.io/javascript-node-js/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://jen-hsuan-hsieh.gitbook.io/javascript-node-js/chapter1/12javascript-quan-gong-lve-ff1a-ke-fu-js-de-qi-guai-bu-fen/125han-shu-jian-gou-zi-3001-300c-new-300d-yu-javascript-de-li-shi/1255wei-xian-xiao-ding-ning-ff1a-nei-jian-de-han-shu-jian-gou-zi.md).

# 1.2.5.5.危險小叮嚀：內建的函數建構子

* 內建的函數建構子很簡潔但也很危險
* 不要將純值轉為物件, 使用真正的純值比較好

```
var a =3;
var b = new Number(3);

//true
a == b

//false
a === b
```

* 處理日期的函式庫: [moment.js](https://momentjs.com/)