Project: A Typed Todo List

Interfaces, unions, generics and narrowing together. Read the code, Run it, then try adding a field to Todo and watch TypeScript point to every place that needs updating.

Exampletypescript

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Now break it: change a status to "finished".

Exampletypescript

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Quick check

Why is `status: Status` better than `status: string`?

It runs fasterOnly the three valid values are accepted, so typos are caughtIt uses less memory

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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