Promises within a chain in JavaScript
Functions within a chain can also return
promises. In this case, the result of
this promise will fall into the next
then:
promise.then(
function(result) {
return result + '1';
}
).then(
function(result) {
return new Promise(function(resolve) {
resolve(result + '2'); // this result will fall into the next then
});
}
).then(
function(result) {
return result + '3';
}
).then(
function(result) {
console.log(result); // shows 'string123'
}
);
