node.js co example

co-example-a.js

co(function* () {
  var a = yield new Promise(function(resolve, reject) {
	   setTimeout(() => resolve("ok"), 100);
  });
  console.log("result: " + a);
  var b = yield new Promise(function(resolve, reject) {
	   setTimeout(() => reject("fail"), 100);
  });
  console.log("result: " + b);
}).catch(function(e) {
  console.log("error: " + e);
});