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⚛️ How to use TypeScript type predicates in React to create a more robust, type-safe, and maintainable component. (this pattern is particularly useful when dealing with discriminated unions or when you need to narrow types based on runtime checks)

George Moller

118,727 subscribers

29,524 views • 1 year ago •via X (Twitter)

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5 Comments

George Moller1 year ago

I've been working professionally with React for more than 8 years and I compiled all my knowledge into 100+ infographics and 70+ video tutorials just like this one. Check them out ↓

Andre de Waard1 year ago

We don’t need this since TS 5.5 right?

Prasenjit1 year ago

Thank you for the check, it's going to be useful.

Pavel Romanov1 year ago

Strange, I've just tested it in TS playground and stackblitz React playground and it narrows the type correctly (with the latest TS version). Maybe it is a problem of some older TS version or less strict TS complier config?

Davide Briano1 year ago

This is automatically narrowed with the latest TS version now 👌🏻

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