Run Async

Utility method to run a function either synchronously or asynchronously using a series of common patterns. This is useful for library author accepting sync or async functions as parameter. `runAsync` will always run them as an async method, and normalize the multiple signature.

# Installation

npm install --save run-async

# Usage

Here's a simple example print the function results and three options a user can provide a function.

var runAsync = require('run-async');
var printAfter = function (func) {
var cb = function (err, returnValue) {
console.log(returnValue);
};
runAsync(func, cb)(/* arguments for func */);
};

#### Using <tt>this.async</tt>

printAfter(function () {
var done = this.async();
setTimeout(function () {
done(null, 'done running with callback');
}, 10);
});

#### Returning a promise

printAfter(function () {
return new Promise(function (resolve, reject) {
resolve('done running with promises');
});
});

#### Synchronous function

printAfter(function () {
return 'done running sync function';
});

### runAsync.cb

`runAsync.cb` supports all the function types that `runAsync` does and additionally a traditional callback as the last argument signature:

var runAsync = require('run-async');
// IMPORTANT: The wrapped function must have a fixed number of parameters.
runAsync.cb(function(a, b, cb) {
cb(null, a + b);
}, function(err, result) {
console.log(result)
})(1, 2)

If your version of node support Promises natively (node >= 0.12), `runAsync` will return a promise. Example: `runAsync(func)(arg1, arg2).then(cb)`

# Licence

Copyright (c) 2014 Simon Boudrias (twitter: @vaxilart)
Licensed under the MIT license.