Type Alias Promisable<T>

Create a type that represents either the value or the value wrapped in PromiseLike.

Use-cases:

• A function accepts a callback that may either return a value synchronously or may return a promised value.
• This type could be the return type of Promise#then(), Promise#catch(), and Promise#finally() callbacks.

Please upvote this issue if you want to have this type as a built-in in TypeScript.

import type {Promisable} from 'type-fest';

async function logger(getLogEntry: () => Promisable<string>): Promise<void> {
	const entry = await getLogEntry();
	console.log(entry);
}

logger(() => 'foo');
logger(() => Promise.resolve('bar'));
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