JSFiddle - React, Tailwind, and code Playground

JavaScript

var username = 'Rose';
new Promise(resolve => {
  resolve('Jack');
})
.then(name => {
  username = name;
  console.log('A:' + username);
})
.then(() => {
  console.log('B:' + username);
})
console.log('C:' + username);

// result:
// C:Rose
// A:Jack
// B:Jack