laser

function procrastinatingAdd(x, y) {
  var errMsg = "Expected number and got ";
  setTimeout(function() {
    if (isNaN(x)) gen.throw(new TypeError(errMsg + typeof x));
    if (isNaN(y)) gen.throw(new TypeError(errMsg + typeof y));
    gen.next(x + y);
  }, 500);
}

var gen = function* () {

laser

setTimeout(function(){
  _get("/something.ajax?greeting", function(err, greeting) {
    if (err) { console.log(err); throw err; }
    _get("/else.ajax?who&greeting="+greeting, function(err, who) {
      if (err) { console.log(err); throw err; }
      console.log(greeting+" "+who);
    });
 });
}, 1000);

laser

sync(function* (resume) {
  try (e) {
    yield setTimeout(resume, 1000);
    var greeting = yield _get('/something.ajax?greeting', resume)
    var who = yield _get('/else.ajax?who&greeting=' + greeting, resume)
    console.log(greeting + ' ' + who)
  }
  catch (e) {
    console.log(e);
    throw e;  

laser

setTimeout(function(){
  _get("/something.ajax?greeting", function(err, greeting) {
    if (err) { console.log(err); throw err; }
    _get("/else.ajax?who&greeting="+greeting, function(err, who) {
      if (err) { console.log(err); throw err; }
      console.log(greeting+" "+who);
    });
 });
}, 1000);

laser

function* fibonacci() {
  var a = 0, b = 1, c = 0;

  while (true) {
    yield a;
    c = a;
    a = b;
    b = c + b;
  }
}

laser

function* powGenerator() {
  var result = Math.pow(yield "a", yield "b");
  return result;
}

var g = powGenerator();
console.log(g.next().value);   // "a", from the first yield
console.log(g.next(10).value); // "b", from the second
console.log(g.next(2).value);  // 100, the result

laser

function* powGenerator() {
  var result = Math.pow(----10----, yield "b");
  return result;
}

laser

function* powGenerator() {
  var result = Math.pow(----10----, ----2----);
  return result;
}

laser

// **************
// framework code

function sync(gen) {
  var iterable, resume;

  resume = function(err, retVal) {
    if (err) iterable.raise(err);
    iterable.next(retVal); // resume!  
  };

laser

try {
  firstAsync(function(err, a) {
    if (err) { console.log(err); throw err; }
    secondAsync(function(err, b) {
      if (err) { console.log(err); throw err; }
      thirdAsync(function(err, c) {
        if (err) { console.log(err); throw err; }
        callback(a, b, c);
      });    
    });