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Check if an object is a Promise

Written byPhuoc Nguyen
Category
Validator
Created
06 May, 2020
Last updated
13 Oct, 2021
Contributors
quantumsheep
JavaScript version
isPromise.js
const isPromise = (obj) =>
!!obj && (typeof obj === 'object' || typeof obj === 'function') && typeof obj.then === 'function';
TypeScript version
isPromise.ts
const isPromise = (obj: any): boolean =>
!!obj && (typeof obj === 'object' || typeof obj === 'function') && typeof obj.then === 'function';

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Phước Nguyễn