docs(update): api docs

.verb.md

@@ -7,7 +7,7 @@
 ## Install
 > Install with [npm](https://www.npmjs.com/)
 
-```sh
+```
 $ npm i {%= name %} --save
 ```
 
@@ -21,6 +21,22 @@ const {%= varname %} = require('{%= name %}')
 ## API
 {%= apidocs('index.js') %}
 
+**non-strict mode**
+
+> passing `false` as second or third argument
+
+```js
+var isAsyncFunction = require('is-async-function')
+
+console.log(isAsyncFunction(fs.readFile, false)) // => 2
+// => 2, because it callback argument is called `cb`
+// and that's the third element in `common-callback-names` array
+
+console.log(isAsyncFunction(fs.stat, false)) // => 1
+// => 1, because it callback argument is called `callback_`
+// and that's the second element in `common-callback-names` array
+```
+
 {% if (verb.related && verb.related.list && verb.related.list.length) { %}
 ## Related
 {%= related(verb.related.list, {words: 12}) %}

README.md

@@ -0,0 +1,133 @@
+# [is-async-function][author-www-url] [![npmjs.com][npmjs-img]][npmjs-url] [![The MIT License][license-img]][license-url] [![npm downloads][downloads-img]][downloads-url] 
+
+> Is function really asynchronous function? Trying to guess that based on check if [common-callback-names][] exists as function arguments names or you can pass your custom.
+
+[![code climate][codeclimate-img]][codeclimate-url] [![standard code style][standard-img]][standard-url] [![travis build status][travis-img]][travis-url] [![coverage status][coveralls-img]][coveralls-url] [![dependency status][david-img]][david-url]
+
+## Install
+> Install with [npm](https://www.npmjs.com/)
+
+```
+$ npm i is-async-function --save
+```
+
+## Usage
+> For more use-cases see the [tests](./test.js)
+
+```js
+const isAsyncFunction = require('is-async-function')
+```
+
+## API
+
+### [isAsyncFunction](index.js#L47)
+> Trying to guess is `fn` asynchronous function or not. But not [is-callback-function][] be aware of that diff.
+
+**Example**
+
+```js
+var fs = require('fs')
+var isAsyncFn = require('is-async-function')
+
+console.log(isAsyncFunction(fs.readFile)) // => true
+console.log(isAsyncFunction(fs.stat)) // => true
+
+console.log(isAsyncFunction(fs.readFileSync)) // => false
+console.log(isAsyncFunction(fs.statSync)) // => false
+
+// or pass custom names to recognize as `async`
+console.log(isAsyncFunction(fs.stat, ['cb'])) // => false
+console.log(isAsyncFunction(fs.readFile, ['foo', 'bar']))
+// => false, because fs.readFile uses `cb`
+```
+
+**Params**
+
+* `fn` **{Function}**: is this `fn` a callback function    
+* `names` **{Array}**: arguments names, default are [common-callback-names][]    
+* `strict` **{Boolean}**: defaults to `true` to always return a boolean, pass `false` to get index (position) - this is useful when you wanna understand which "callback name" exists as argument in that `fn`    
+* `returns` **{Boolean|Number}**: always boolean `true` or `false` when on strict mode, othewise it can be Number index representing the position and if index is 0 it is transformed to boolean `true` - so always positive value if function is async.  
+
+**non-strict mode**
+
+> passing `false` as second or third argument
+
+```js
+var isAsyncFunction = require('is-async-function')
+
+console.log(isAsyncFunction(fs.readFile, false)) // => 2
+// => 2, because it callback argument is called `cb`
+// and that's the third element in `common-callback-names` array
+
+console.log(isAsyncFunction(fs.stat, false)) // => 1
+// => 1, because it callback argument is called `callback_`
+// and that's the second element in `common-callback-names` array
+```
+
+## Related
+- [common-callback-names](https://www.npmjs.com/package/common-callback-names): List of common callback names - callback, cb, callback_, next, done. | [homepage](https://github.com/tunnckocore/common-callback-names#readme "List of common callback names - callback, cb, callback_, next, done.")
+- [fn-args](https://www.npmjs.com/package/fn-args): Get the arguments of a function | [homepage](https://github.com/sindresorhus/fn-args "Get the arguments of a function")
+- [fn-name](https://www.npmjs.com/package/fn-name): Get the name of a named function | [homepage](https://github.com/sindresorhus/fn-name "Get the name of a named function")
+- [function-arguments](https://www.npmjs.com/package/function-arguments): Get arguments of a function, useful for and used in dependency injectors… [more](https://github.com/tunnckocore/function-arguments#readme) | [homepage](https://github.com/tunnckocore/function-arguments#readme "Get arguments of a function, useful for and used in dependency injectors. Works for regular functions, generator functions and arrow functions.")
+- [get-fn-name](https://www.npmjs.com/package/get-fn-name): Get function name with strictness and correctness in mind. Also works for… [more](https://github.com/tunnckocore/get-fn-name#readme) | [homepage](https://github.com/tunnckocore/get-fn-name#readme "Get function name with strictness and correctness in mind. Also works for arrow functions and getting correct name of bounded functions. Powered by [fn-name][].")
+- [is-callback-function](https://www.npmjs.com/package/is-callback-function): Returns true if function is a callback. Checks its name is one… [more](https://github.com/tunnckocore/is-callback-function#readme) | [homepage](https://github.com/tunnckocore/is-callback-function#readme "Returns true if function is a callback. Checks its name is one of [common-callback-names][] - callback, cb, cb_, callback_, next, done, they can be customized, these are default.")
+- [parse-function](https://www.npmjs.com/package/parse-function): Parse a function, arrow function or string to object with name, args… [more](https://github.com/tunnckocore/parse-function#readme) | [homepage](https://github.com/tunnckocore/parse-function#readme "Parse a function, arrow function or string to object with name, args, params and body properties.")
+
+## Contributing
+Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](https://github.com/tunnckoCore/is-async-function/issues/new).  
+But before doing anything, please read the [CONTRIBUTING.md](./CONTRIBUTING.md) guidelines.
+
+## [Charlike Make Reagent](http://j.mp/1stW47C) [![new message to charlike][new-message-img]][new-message-url] [![freenode #charlike][freenode-img]][freenode-url]
+
+[![tunnckoCore.tk][author-www-img]][author-www-url] [![keybase tunnckoCore][keybase-img]][keybase-url] [![tunnckoCore npm][author-npm-img]][author-npm-url] [![tunnckoCore twitter][author-twitter-img]][author-twitter-url] [![tunnckoCore github][author-github-img]][author-github-url]
+
+[common-callback-names]: https://github.com/tunnckocore/common-callback-names
+[function-arguments]: https://github.com/tunnckocore/function-arguments
+[is-callback-function]: https://github.com/tunnckocore/is-callback-function
+
+[npmjs-url]: https://www.npmjs.com/package/is-async-function
+[npmjs-img]: https://img.shields.io/npm/v/is-async-function.svg?label=is-async-function
+
+[license-url]: https://github.com/tunnckoCore/is-async-function/blob/master/LICENSE
+[license-img]: https://img.shields.io/npm/l/is-async-function.svg
+
+[downloads-url]: https://www.npmjs.com/package/is-async-function
+[downloads-img]: https://img.shields.io/npm/dm/is-async-function.svg
+
+[codeclimate-url]: https://codeclimate.com/github/tunnckoCore/is-async-function
+[codeclimate-img]: https://img.shields.io/codeclimate/github/tunnckoCore/is-async-function.svg
+
+[travis-url]: https://travis-ci.org/tunnckoCore/is-async-function
+[travis-img]: https://img.shields.io/travis/tunnckoCore/is-async-function/master.svg
+
+[coveralls-url]: https://coveralls.io/r/tunnckoCore/is-async-function
+[coveralls-img]: https://img.shields.io/coveralls/tunnckoCore/is-async-function.svg
+
+[david-url]: https://david-dm.org/tunnckoCore/is-async-function
+[david-img]: https://img.shields.io/david/tunnckoCore/is-async-function.svg
+
+[standard-url]: https://github.com/feross/standard
+[standard-img]: https://img.shields.io/badge/code%20style-standard-brightgreen.svg
+
+[author-www-url]: http://www.tunnckocore.tk
+[author-www-img]: https://img.shields.io/badge/www-tunnckocore.tk-fe7d37.svg
+
+[keybase-url]: https://keybase.io/tunnckocore
+[keybase-img]: https://img.shields.io/badge/keybase-tunnckocore-8a7967.svg
+
+[author-npm-url]: https://www.npmjs.com/~tunnckocore
+[author-npm-img]: https://img.shields.io/badge/npm-~tunnckocore-cb3837.svg
+
+[author-twitter-url]: https://twitter.com/tunnckoCore
+[author-twitter-img]: https://img.shields.io/badge/twitter-@tunnckoCore-55acee.svg
+
+[author-github-url]: https://github.com/tunnckoCore
+[author-github-img]: https://img.shields.io/badge/github-@tunnckoCore-4183c4.svg
+
+[freenode-url]: http://webchat.freenode.net/?channels=charlike
+[freenode-img]: https://img.shields.io/badge/freenode-%23charlike-5654a4.svg
+
+[new-message-url]: https://github.com/tunnckoCore/ama
+[new-message-img]: https://img.shields.io/badge/ask%20me-anything-green.svg
+
+[fn-name]: https://github.com/sindresorhus/fn-name

index.js

@@ -27,8 +27,8 @@ var utils = require('./utils')
  *
  * // or pass custom names to recognize as `async`
  * console.log(isAsyncFunction(fs.stat, ['cb'])) // => false
- * console.log(isAsyncFunction(fs.readFile, ['callback', 'next']))
- * // => false, because fs.readFile uses `callback_`
+ * console.log(isAsyncFunction(fs.readFile, ['foo', 'bar']))
+ * // => false, because fs.readFile uses `cb`
  * ```
  *
  * @param  {Function} `fn` is this `fn` a callback function
@@ -37,7 +37,10 @@ var utils = require('./utils')
  *                            pass `false` to get index (position) - this is
  *                            useful when you wanna understand which "callback name"
  *                            exists as argument in that `fn`
- * @return {Boolean}
+ * @return {Boolean|Number} always boolean `true` or `false` when on strict mode,
+ *                          othewise it can be Number index representing the position
+ *                          and if index is 0 it is transformed to boolean `true` - so
+ *                          always positive value if function is async.
  * @api public
  */