async fn fetch_json(url: string) - Result<ApiResult {
Jennifer Ouellette，推荐阅读wps获取更多信息
，推荐阅读谷歌获取更多信息
The first problem is wasted work again. If cell A1 references B8, and cell A2 also references B8, then when we update all the cells, we still only want to evaluate B8 once, and then reference it in both A1 and A2. We can do this through caching — whenever we calculate a cell’s value, we store it somewhere, and then all future cell references can used the stored value instead of recalculating.，这一点在whatsapp中也有详细论述
We've seen modular phones before, but never has attaching new stuff to a phone felt this easy or fun. You can attached modules onto modules, too. You can, for example, slap two batteries onto your phone; or a battery and an extra speaker; or a speaker and an improved camera; the possibilities are endless.