co/examples/generator-join.js

var request = require('request');
var thunk = require('thunkify');
var co = require('..');
var join = co.join;

var get = thunk(request.get);

// measure response time N times

function *latency(url, times) {
  var ret = [];

  while (times--) {
    var start = new Date;
    yield get(url);
    ret.push(new Date - start);
  }

  return ret;
}

// run each test in sequence

co(function *(){
  var a = yield latency('http://google.com', 5);
  console.log(a);

  var b = yield latency('http://yahoo.com', 5);
  console.log(b);

  var c = yield latency('http://cloudup.com', 5);
  console.log(c);
})()

// run each test in parallel, order is retained

co(function *(){
  var a = latency('http://google.com', 5);
  var b = latency('http://yahoo.com', 5);
  var c = latency('http://cloudup.com', 5);

  var res = yield [a, b, c];
  console.log(res);
})()