add comments reduxjs#2

src/components/connectAdvanced.js

@@ -160,6 +160,7 @@ export default function connectAdvanced(
     const usePureOnlyMemo = pure ? useMemo : callback => callback()
 
     function ConnectFunction(props) {
+      // 这里的useMemo
       const [propsContext, forwardedRef, wrapperProps] = useMemo(() => {
         // Distinguish between actual "data" props that were passed to the wrapper component,
         // and values needed to control behavior (forwarded refs, alternate context instances).