coPromise.js

function coPromise (genFun, ctx) {
	return new Promise(function (resolve, reject) {
		co(genFun).call(ctx, function (err, data) {
			if (err) {
				return reject(err);
			}
			
			resolve(data);
		});
	});
}

Helper function for handling async operations using co module and ES6 promises.

e.g.

// @returns promise
function loadData () {
   return coPromise(function* () {
      var data1 = yield getData1();
      var result = null;

      try {
          result = yield getData2(data1);
      }
      catch (ex) {
          // this will reject promise
          throw new Error("Error while loading data.");
      }

      // this will resolve promise with value result
      return result;
   }, this);
}

// call function here
loadData()
   .then(function (data) {
       // do some stuff
   })
   .catch(function (err) {
       // handle error here
   });