hg-pyun

// ES6
function* foo(){
  yield bar();
}

// ES5 Compiled
"use strict";

var _marked = /*#__PURE__*/ regeneratorRuntime.mark(foo);

hg-pyun

// ES7
async function foo() {
  await bar();
}

// ES5 complied
let foo = (() => {
  var _ref = _asyncToGenerator(function*() {
    yield bar();
  });

hg-pyun

function* fibonacci() {
  let [prev, curr] = [1, 1];
  while (true) {
    [prev, curr] = [curr, prev + curr];
    yield curr;
  }
}

for (let n of fibonacci()) {
  console.log(n);

hg-pyun

function* idMaker(){
  var index = 0;
  while(index < 3)
    yield index++;
}

const gen = idMaker();

console.log(gen.next().value); // 0
console.log(gen.next().value); // 1

hg-pyun

const arr = [...Array(100).keys()].map(i => 0);
console.log(arr);

hg-pyun

const arr = [];
for(let i=0; i<100; i++) {
  arr.push(0);
}
console.log(arr);

hg-pyun

const iterable = {
  [Symbol.iterator]() {
    return {
      i: 0,
      next() {
        if (this.i < 3) {
          return { value: this.i++, done: false };
        }
        return { value: undefined, done: true };
      }

hg-pyun

function makeRangeIterator(start = 0, end = Infinity, step = 1) {
    var nextIndex = start;
    var n = 0;
    
    var rangeIterator = {
       next: function() {
           var result;
           if (nextIndex < end) {
               result = { value: nextIndex, done: false }
           } else if (nextIndex == end) {

hg-pyun

/* array */
let iterable = [10, 20, 30];

for (let value of iterable) {
  console.log(value); // 10 20 30
}

/* string */
let iterable = "boo";

hg-pyun

renderHtmlTag = tagName => content => `<${tagName}>${content}</${tagName}>`
renderDiv = renderHtmlTag('div')
renderH1 = renderHtmlTag('h1')

console.log(
  renderDiv('this is a really cool div'),
  renderH1('and this is an even cooler h1')
)