Typescript: How can I use the `Promise.allSettled` method using TypeScript?

[lffg]

TypeScript Version: 3.6.2

Search Terms: promise promise.allSettled allSettled

Node.js 12.x already supports the Promise.allSettled method, as you see by running the following command:

node -e "console.log(typeof Promise.allSettled);"

How can I use this method in TypeScript?

There is a compiler option which enables this method?

[kitsonk]

This is not a support forum.

Questions should be asked at StackOverflow or on Gitter.im.

[lffg]

I am aware of that. I created this issue because I think that this is kind of a "problem" that should be fixed.

If Promise.allSettled is an ECMAScript feature and its not included in TS's standard library, why this should be considered a "support forum" question?

[AnyhowStep]

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/allSettled

According to mdn,

• Stage 4
• Supported by Chrome, Opera, node

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If it isn't in the lib.d.ts files, you can work around the problem by using declaration merging,

https://www.typescriptlang.org/docs/handbook/declaration-merging.html

[kitsonk]

Also, omissions or additions the the lib files are covered under CONTRIBUTING.md libdts fixes.

As @AnyhowStep says, they can be added yourself, until they are available in a released version of TypeScript.

[lffg]

I see. Thanks, guys. :)

[Crusader4Christ]

If it isn't in the lib.d.ts files, you can work around the problem by using declaration merging,

https://www.typescriptlang.org/docs/handbook/declaration-merging.html

Sorry, I tried to understand this doc but I couldn't.
And I read lots of similar question - nobody can. How I can extend interface declared in some other file?

[pyrho]

For anyone still confused, setting "compilerOptions": {"target": "ES2020"} in your tsconfig.json will allow you to use Promise.allSettled.

[daffl]

Using TypeScript v3.8 or later, if you do not want to change the compilation target you can also add ES2020.Promise to the lib array in the compilerOptions in tsconfig.json:

"lib": [ "ES2020.Promise" ], /* Specify library files to be included in the compilation. */