visionmedia/co — pull request #112 by talrasha007 (2014-04-23 08:00:20+00:00)
Title: optimize performance.

look at this bench:

```js
var co = require('co');
var foo = function *(){};

co(function * () {
for (var i = 0; i < 1000 * 1000; i++) {
yield foo();
}
})(function (err) {
if (err) console.log(err);
});
```

The original version's result is:
real 0m7.985s
user 0m7.622s
sys 0m0.373s

And my version's result is:
real 0m1.465s
user 0m1.446s
sys 0m0.017s

It's much faster, and I think the behavior of my version is exactly the same as origin (my node version is node 0.11.11).
What do you think?

:)