An error boundary in React

React interview exercise on Patterns, difficulty 2 of 3. Solve it in the editor beside a worked example; the tests run the moment you do.

Write ErrorBoundary({ fallback, children }) where fallback is a function (error, reset) => ReactNode: render the children; when one of them throws during render, render fallback with the error and a reset function that renders the children again. Healthy children render untouched.

Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Progress is saved in your browser, and in your account if you sign in.

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