28 lines
1.0 KiB
Plaintext
28 lines
1.0 KiB
Plaintext
/**
|
|
Returns the type that is wrapped inside a `Promise` type.
|
|
If the type is a nested Promise, it is unwrapped recursively until a non-Promise type is obtained.
|
|
If the type is not a `Promise`, the type itself is returned.
|
|
|
|
@example
|
|
```
|
|
import {PromiseValue} from 'type-fest';
|
|
|
|
type AsyncData = Promise<string>;
|
|
let asyncData: PromiseValue<AsyncData> = Promise.resolve('ABC');
|
|
|
|
type Data = PromiseValue<AsyncData>;
|
|
let data: Data = await asyncData;
|
|
|
|
// Here's an example that shows how this type reacts to non-Promise types.
|
|
type SyncData = PromiseValue<string>;
|
|
let syncData: SyncData = getSyncData();
|
|
|
|
// Here's an example that shows how this type reacts to recursive Promise types.
|
|
type RecursiveAsyncData = Promise<Promise<string> >;
|
|
let recursiveAsyncData: PromiseValue<RecursiveAsyncData> = Promise.resolve(Promise.resolve('ABC'));
|
|
```
|
|
*/
|
|
export type PromiseValue<PromiseType, Otherwise = PromiseType> = PromiseType extends Promise<infer Value>
|
|
? { 0: PromiseValue<Value>; 1: Value }[PromiseType extends Promise<unknown> ? 0 : 1]
|
|
: Otherwise;
|