30-seconds-of-code/snippets/js/s/is-async-function.md

title, type, language, tags, author, cover, dateModified

title	type	language	tags	author	cover	dateModified
Value is async function	snippet	javascript	type function	chalarangelo	interior-12	2020-10-20T11:21:07+03:00

Checks if the given argument is an async function.

• Use Object.prototype.toString() and Function.prototype.call() and check if the result is '[object AsyncFunction]'.

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

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