Scenarioany, unknown, and never5 minLesson 22 of 4

Production throws a runtime TypeError ('Cannot read properties of undefined') on a field that TypeScript's types say can never be undefined. How do you find where the type safety broke down?

Illustration for the lesson: Production throws a runtime TypeError ('Cannot read properties of undefined') on a field that TypeScript's types say can never be undefined. How do you find where the type safety broke down?

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