playing with generators

gistfile1.js

var Q = require('Q');
var fs = require('fs');


var generator = Q.async(function* () {
  yield 10
  console.log('yielded 10');
  yield 20
  console.log('yielded 20');
  yield 30
  console.log('yielded 30');
  return 40;
});

generator().then(function(last) {
  console.log(last);
});

function readFile(filename, enc){
  return new Promise(function (fulfill, reject){
    fs.readFile(filename, enc, function (err, res){
      if (err) reject(err)
        else fulfill(res)
    })
  })
}

var readJSON = Q.async(function* (filename) {
  return JSON.parse(yield readFile(filename, 'utf8'));
});

Q.spawn(function* () {
  var content = yield readJSON('foo.json', 'utf8');
  console.log(content);
});