Awaited

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Problem Description

If we have a type which is a wrapped type like Promise, how we can get the type which is inside the wrapped type?

For example: if we have Promise<ExampleType> how to get ExampleType?

type ExampleType = Promise<string>
 
type Result = MyAwaited<ExampleType> // string

Solutions

Approach 1: infer

type MyAwaited<T extends PromiseLike<any>> = T extends PromiseLike<infer Wrapped>
	? Wrapped extends PromiseLike<any>
		? MyAwaited<Wrapped>
		: Wrapped
	: never;