Beginner's TypeScript Section 18 exercises

Selectively Construct Types from Other Types

We've looked at inheriting and combining types.

But what if we want to be more selective?


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0:00 We're continuing our Odyssey here of creating types from other types. It's really, really useful in TypeScript to be able to extract bits of a type and then create new ones out of it. Here, we've got our user type. What we want to do is create a new type here which is just the firstName and lastName properties of the user type.

0:23 How do we create an object type which is just those? We've got our test down here which is saying we want it to be firstName, lastName. The thing I want you to google in the TypeScript doc is utility types. There are various built-in utilities in TypeScript that I want you to see if you can have a look at. See if you can piece them together to work out how to create this MyType here.