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React app re-render

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 causes:

1.   state/props change

2. context change - parent render

In normal rendering, React does not care whether “props changed” - it will render child components unconditionally just because the parent rendered!

If you wrap a component in memo, it won’t re-render when its parent renders.

Should I memo everything?

If memo has such a great effect on performance, does it make sense to wrap everything with it? Well, not really.




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