Fix handleClick compiler intro example #7967
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Size changes📦 Next.js Bundle Analysis for react-devThis analysis was generated by the Next.js Bundle Analysis action. 🤖 This PR introduced no changes to the JavaScript bundle! 🙌 |
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| Even though `handleClick` is wrapped in `useCallback`, the arrow function `() => handleClick(item)` creates a new function every time the component renders. This means that `Item` will always receive a new `onClick` prop, breaking memoization. | ||
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| The React Compiler is able to optimize this correctly with or without the arrow function, ensuring that `Item` only re-renders when `props.onClick` changes. |
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nit: drop the "the", just React Compiler
josephsavona
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poteto
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rickhanlonii
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Found by @gmoniava in #7734 (comment)
In the current version, passing an arrow function to the child breaks manual memoization, which means it's not an "equivalent" memoization like the text says.
This is actually a subtle bug that the compiler prevents - the compiler output for this does memoize correctly on
onClickeven with the function. That may be a good example to call out if we want to add to these docs.This PR adds a note to call out the subtle bug, and explain how the Compiler works with or without the arrow function.
