Improve Promise type definition #10448
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| * Creates a new Promise with the same internal state of this Promise. | ||
| * @returns A Promise. | ||
| */ | ||
| then(): Promise<T>; |
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I thought overloads should be arranged longest-to-shortest to make sure that the most restrictive overloads matches first. Why change that here?
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The change in 9d4219a fixes an existing issue with assignability between |
| @@ -8,42 +8,45 @@ interface Promise<T> { | |||
| * @param onrejected The callback to execute when the Promise is rejected. | |||
| * @returns A Promise for the completion of which ever callback is executed. | |||
| */ | |||
| then<TResult1, TResult2>(onfulfilled: (value: T) => TResult1 | PromiseLike<TResult1>, onrejected: (reason: any) => TResult2 | PromiseLike<TResult2>): Promise<TResult1 | TResult2>; | |||
| then(onfulfilled?: ((value: T) => T | PromiseLike<T>) | undefined | null, onrejected?: ((reason: any) => T | PromiseLike<T>) | undefined | null): Promise<T>; | |||
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This overload is meant to replace then(): Promise<T> as that overload was one of the causes of #10524.
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@mhegazy, do you want to take this change for release-2.0 as well? |
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no. jsut 2.1 please. |
This change modifies the overloads for
thenandcatchofPromise<T>, and the overloads forthenofPromiseLike<T>to provide better type inference.Fixes #4903