promises.js

fetchSomeStuff().then(
    function (a) {
        return fetchSomeStuffDependingOnA(a);
    }
).then(
    function (b) {
        return fetchSomeStuffDependingOnB(b);
    }
).then(
    function (c) {
        /* Code goes on here */
    }
).catch(
    function (ex) {
        handleException(ex);
    }
);