Value Is Async Function

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Introduction

In this lab, we will explore the concept of asynchronous functions in JavaScript. We will learn how to recognize and differentiate between regular functions and async functions using the isAsyncFunction() method. By the end of this lab, you will have a clear understanding of how to work with asynchronous functions and how they can be used to improve the performance of your code.


Skills Graph

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Check if a Value is an Async Function in JavaScript

To check if a value is an async function in JavaScript, you can use the following code:

const isAsyncFunction = (val) =>
  Object.prototype.toString.call(val) === "[object AsyncFunction]";

This function uses Object.prototype.toString() and Function.prototype.call() to check whether the given argument is an async function.

You can test the function by passing a regular function and an async function as arguments:

isAsyncFunction(function () {}); // false
isAsyncFunction(async function () {}); // true

To start practicing coding in JavaScript, open the Terminal/SSH and type node.

Summary

Congratulations! You have completed the Value Is Async Function lab. You can practice more labs in LabEx to improve your skills.

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