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@theKashey This is what I wanted and looks ok.

// will look again
console.log(
  getItemA({ state: prevState, id: 3 }) === getItemA({ state, id: 3 })
);

👍 , this was a little issue for memoize-state, as nested memoization was doing parent one a little unstable - "affected" keys were changing every time.
I was considering something like touchAffected, but in my case, the underlying memoization was reselect based.

During memoize-state development I added a shallBePure helper, which just runs memoization twice to check that function is pure. Just to found that state access is a part of function pureness.

This touched moment is a missing piece. Thank's @dai-shi, I'll make my stuff a little bit touched as well.

I was just about to create a redux example, and found unexpected behavior. Maybe a bug... 🤔

https://codesandbox.io/s/proxy-memoize-demo-forked-fi5ni?file=/src/App.tsx
I finally made this work. I suppose this is the best we can do with proxy and weakmap combination.