CommonJS 规范下,require() 在引入外部包的时候是属于同步加载的
AMD 规范下,require([module], callback) 引包可以实现异步加载
https://www.cnblogs.com/chenguangliang/p/5856701.html
https://segmentfault.com/a/1190000012138052
https://cn.vuejs.org/v2/guide/components-dynamic-async.html#%E5%BC%82%E6%AD%A5%E7%BB%84%E4%BB%B6
https://blog.csdn.net/weixin_38704338/article/details/79103230
https://router.vuejs.org/zh/guide/advanced/lazy-loading.html#%E6%8A%8A%E7%BB%84%E4%BB%B6%E6%8C%89%E7%BB%84%E5%88%86%E5%9D%97