Some snippets of ES7

ES7.js

function makeRequest(id) {
  return new Promise((resolve, reject) => {  
    setTimeout(() => {
      if (id % 2) {
        resolve(id);
      } else {
        reject(id);
      }
    }, 400);
  });
}

async function resourceCrawler() {
  const result = [];
  for (let id = 1; id < 10; id++) {
    try {
      const response = await makeRequest(id);
      result.push(response);
    } catch (err) {
      console.log(`No resource on id: ${id}`);
    }
  }
  return result;
}

resourceCrawler()
  .then((res) => console.log(`Resources @ ${res}`));

//-------------------------

function* range(from, to, step = 1) {
  for (let i = from; i <= to; i += step) {
  	yield i;
  }
}

console.log([...range(1, 5)])