https://github.com/loklaan/is-async-func

Check if a value is an async function, from ES2017 specification. Supports babel.
https://github.com/loklaan/is-async-func

async-functions es2017 type-checking

Last synced: about 2 months ago
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Check if a value is an async function, from ES2017 specification. Supports babel.

• Host: GitHub
• URL: https://github.com/loklaan/is-async-func
• Owner: loklaan
• Created: 2017-04-02T08:38:10.000Z (over 8 years ago)
• Default Branch: master
• Last Pushed: 2022-12-06T20:40:28.000Z (almost 3 years ago)
• Last Synced: 2025-08-16T15:58:28.548Z (about 2 months ago)
• Topics: async-functions, es2017, type-checking
• Language: JavaScript
• Homepage: https://www.npmjs.com/package/is-async-func
• Size: 245 KB
• Stars: 3
• Watchers: 1
• Forks: 0
• Open Issues: 8
• Metadata Files:
  • Readme: readme.md

Awesome Lists containing this project

README

          
# is-async-func

![size](https://img.shields.io/badge/size-282%20B-grey.svg)

![dependencies](https://img.shields.io/badge/dependencies-0-grey.svg)

[![NPM](https://img.shields.io/npm/v/is-async-func.svg)](https://npmjs.com/package/is-async-func)

[![Travis](https://img.shields.io/travis/loklaan/is-async-func.svg)](https://travis-ci.org/loklaan/is-async-func)

[![Codecov](https://img.shields.io/codecov/c/github/loklaan/is-async-func.svg)](https://codecov.io/gh/loklaan/is-async-func)

Check if a value is an async function, from ES2017 specification

Supports runtime implementations, as well as babel transpiled code.

```js

const isAsyncFunction = require('is-async-func');

isAsyncFunction(async function () {})

// true

isAsyncFunction(async function foo () {})

// true

isAsyncFunction(async () => {})

// true

const foo = { async bar () {} }

isAsyncFunction(foo.bar)

// true

const foo = { bar: async function () {} }

isAsyncFunction(foo.bar)

// true

const foo = { bar: async () => {} }

isAsyncFunction(foo.bar)

// true

class Foo () {

  async bar () {}

}

isAsyncFunction((new Foo()).bar)

// true

```

## Install

```shell

npm install is-async-func

# yarn add is-async-func

```

## Should I use this?

For runtimes that support async/await, yes!

For transpiled async/await, probably! :grimacing:  

The transpilation tests cover many different combinations of async declarations and babel transform presets, but the transpiled detection generally takes a hacky approach. Probably-definitely don't use this in hot code.

## License

Licensed under the MIT License, Copyright © 2017 Lochlan Bunn.