https://blog.csdn.net/gc258_2767_qq/article/details/81003656
为什么spreadsheet有时候会输出错误语法错误
大概率是你的单元格内容又 $==之类的与 excel 的计算格式冲突的问题
https://blog.csdn.net/yanzisu_congcong/article/details/82220186
https://www.cnblogs.com/yaohuimo/p/6910282.html
https://www.jianshu.com/p/512dde9376da
https://www.cnblogs.com/nx520zj/p/9617689.html
https://www.cnblogs.com/yaowen/p/8353444.html
https://github.com/webmozart/assert/blob/master/src/Assert.php
https://developer.mozilla.org/zh-CN/docs/Web/JavaScript
https://www.cnblogs.com/chinabin1993/p/9115396.html
css的calc函数
https://www.runoob.com/cssref/func-calc.html
https://zengweigang.gitbooks.io/core-go/eBook/08.2.html
原文：https://www.cnblogs.com/xuweiqiang/p/12290062.html