what is promise chaining code example

Example 1: javascript promise chain

// base case 
promise
  .then(...)
  .then(...)
  .then(...)
  .catch(...)

//real world
coinflip(10)
  .then(betAgain)
  .then(betAgain)
  .then(betAgain)
  .then(result => {
    console.log(`OMG, WE DID THIS! TIME TO TAKE ${result} HOME!`);
  })
  .catch(handleRejection);

Example 2: promise chaining

new Promise(function(resolve, reject) {

  setTimeout(() => resolve(1), 1000); // (*)

}).then(function(result) { // (**)

  alert(result); // 1
  return result * 2;

}).then(function(result) { // (***)

  alert(result); // 2
  return result * 2;

}).then(function(result) {

  alert(result); // 4
  return result * 2;

});