30-seconds-of-code/snippets/isAsyncFunction.md

title, tags

title	tags
isAsyncFunction	type,function,intermediate

Checks if the given argument is an async function.

Use Object.prototype.toString() and Function.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