JavaScript Promises, road to async/await - https://codingblast.com/javascript-promise-async-await

async.js

function someFunction(value, error) {
 return new Promise(
  function (resolve, reject) {
   if (value) {
    resolve(value);
   } else {
    reject(error);
   }
  });
}

async function mainFunction() { 
  let value = await someFunction('CodingBlast');
  console.log(value);
}

mainFunction();