Types in object destructuring

typescript destructuring
Estus Flask picture Estus Flask · Sep 24, 2016 · Viewed 51.4k times · Source

This

const { foo: IFoo[] } = bar;

and this

const { foo: Array<IFoo> } = bar;

will reasonably cause an error.

And this

const { foo: TFoo } = bar;

will just destructure TFoo property.

How can types be specified for destructured object properties?

Answer

artem picture artem · Sep 24, 2016

It turns out it's possible to specify the type after : for the whole destructuring pattern:

const {foo}: {foo: IFoo[]} = bar;

Which in reality is not any better than plain old

const foo: IFoo[] = bar.foo;

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