Vow: the fastest promises

I want to bring to your attention the Vow library , which was written by my colleague Dmitry Filatov dfilatov .

The library implements Promises / A + , works very fast and requires a small amount of memory. According to performance tests, it is far ahead of Q , but at the same time it retains an asynchronous manner of work.

Working with the Vow is as easy as working with the Q . Of the shortcomings (compared to Q ), we can only highlight the lack of progress .

Sample code using Vow :

function readFile(filename, encoding) {
    var promise = Vow.promise();
    fs.readFile(filename, encoding, function(err, data) {
        if (err) return promise.reject(err);
        promise.fulfill(data);
    });
    return promise;
}
Vow.all([readFile('test1.txt', 'utf8'), readFile('test2.txt', 'utf8')]).then(function(results) {
    console.log(results.join('\n'));
});

A benchmark that reflects how Q is a slow library (testing the creation of sequential promises is tested):

	time	operations per second
Q	54.891ms	18
When	3.484ms	287
Vow	1.158ms	864

Also, a library for working with the file system is implemented for Vow: vow-fs : https://github.com/dfilatov/vow-fs .

NPM Package: vow
Repository: https://github.com/dfilatov/jspromise