https://zh.wikipedia.org/wiki/%E7%93%A6%E8%90%A8%E5%8F%B7 https://esdiscuss.org/topic/do-maximally-minimal-classes-carry-their-weight https://medium.com/@igorchulinda/class-fields-proposal-or-what-went-wrong-in-tc39-committee-6ce41efe291 https://docs.google.com/presentation/d/1wgus0BykoVk_qqCpr0TjgO0TV0Y4ql4d9iY212phzbY/edit#slide=id.p https://github.com/tc39/tc39-notes/blob/master/es8/2017-11/nov-30.md#10iva-continued-inheriting-private-static-class-elements-discussion-and-resolution
PrivateName leak in decorators tc39/proposal-decorators#24
https://reactjs.org/blog/2016/07/13/mixins-considered-harmful.html https://medium.com/@dan_abramov/mixins-are-dead-long-live-higher-order-components-94a0d2f9e750