How to iterate over the results of a generator function

for ... of is the elegant solution but not overall supported, however while (!(next = cursor.next()).done) { is a very cryptic, and one might ask himself, how come (var x = someFunctionCall()) is evaluated to true and another would answer welcome to javascript.

For that reason and to and give the answer another shape, it can also be done using a recursive function.

function loopThose(items) {
    const item = items.next();

    // doStuff(item);

    if (!item.done) {
        loopThose(items);
    }
}

A true benefit is when async, try catch and custom continue condition come into play:

async function printKeys(items) {
    try {
       const item = await items.next();
       // doStuff(item);
       if (isConditionFulfil(item)) {
          await this.printKeys(items);
       }
    } catch (e){

    }
}

Where a generator function yields promises that might fail:

function * list(){
  for (var i = 0; i<10; i++){
     yield fetch(buildResourceUrl(i)).then(res => res.json())
  }
}

Yes, if your environment already supports for...of:

for (var job of readyJob) {
  // ...
}

If not, have seen this a couple of times:

var next;
while (!(next = readyJob.next()).done) {
   var job = next.value;
   // ...
}