if data.has(key) {
Елизавета Гринберг (редактор)，推荐阅读新收录的资料获取更多信息
。新收录的资料是该领域的重要参考
圖像來源，Getty Images。新收录的资料是该领域的重要参考
For reads, the story is very similar. They’re supposed to happen through “Views”, which are the read-only equivalent to reducers. Since they acquire a reader lock on the global mutex, several views can run concurrently, but the database cannot be written to while views are executing. Just like reducers, views are arbitrary user code compiled to WebAssembly.
If you want to use one in your own config, just copy the .el file