Helper method for node functions

[guybedford]

I find myself defining this in every single source file when I'm using promises in NodeJS:

function asp(fn) {
  return function() {
    var self = this;
    var args = Array.prototype.splice.call(arguments, 0);
    return new Promise(function(resolve, reject) {
      args.push(function(err, val) {
        if (err)
          return reject(err);
        resolve(val);
      });
      fn.apply(self, args);
    });    
  }
}

So you can do things like:

  asp(fs.readFile)('some/file').then(function(content) {
  });

Does this seem sensible? Is there a helper that already does this? Can we make a helper that does so this solution doesn't need to be repeated?

[stefanpenner]

The parent library that this one comes from is RSVP and it has a helper method called denodify. This library will not include it as it is the bare bones es6 promises

[guybedford]

Amazing, thanks - I'll use that! Is there documentation on this somewhere?

[stefanpenner]

@guybedford https://github.com/tildeio/rsvp.js/blob/master/lib/rsvp/node.js#L6-L133

[guybedford]

Thanks!