Promisify a function call so users can call a function with a callback or get a promise
npm install promisify-call

Promisify a function call so users can call a function with a callback or get a promise.
* 2.0 works only with native Promise so requires Node >= 4.0.
* 1.0 uses Bluebird and should work with older Node.js
npm install promisify-call
``js
function _uppercase(param, fn) {
setTimeout(() => {
return fn(null, param.toUpperCase());
}, 50);
}
function uppercase(param, fn) {
return promisifyCall(this, _uppercase, ...arguments);
}
// now we can call it using callback-style
uppercase('foo', (err, res) => {
console.log(res); // FOO
});
// OR promise style
const res = await uppercase('foo');
console.log(res); // FOO
``
fn if appropriate given the arguments.fn either using callback style if last argument is a function.fn is called returning a promise.Kind: global function
Returns: undefined | \* | Promise - Promise if promisified
| Param | Type | Description |
| --- | --- | --- |
| ctx | Object | context / this |
| fn | function | The function to call |
| args | arguments | Arguments |
Copyright 2015 Bojan D.
Licensed under the MIT License.