JS Bin// source https://jsbin.com/kikinoy

promiseExample.js

function promissDemo(){
  new Promise(function(resolve, reject){
    setTimeout(function(){
      console.log('200');
      resolve()
    }, 200);
  }).then(function(fromResolve){
    setTimeout(function(){
      console.log('100');
      //resolve('hello')
    }, 100);
  });
}

promissDemo();