Possible conceptual pitfall when discussing accessing a state variable set in a previous render

Hi there!

In this section: https://react.dev/learn/you-might-not-need-an-effect#adjusting-some-state-when-a-prop-changes

It took me a while to understood that prevItems would not be changed until setItems was invoked on it. What tripped me there was that I thought that useState(X) always set items to X on every re-render. Once I understood that prevItems is set to X only when the state is initialized, everything is clear.

This might perhaps be a good place in the docs to clarify (either on a couple of sentences or on its own Pitfall section) that setState will only initialize a value, but not update it during a re-render.

I take this opportunity for congratulating the team on the new React docs. There are one of the best technical documentation pieces I've read in my entire career. 🚀

Read the linked “Adjusting some state when a prop changes” section in the React documentation and inspect its explanation of useState and setState across renders. Done means the section clearly distinguishes initial state initialization from later updates and addresses the reported misunderstanding.