payment-promises.js

var promise = paymentRequest(supportedInstruments, details, schemeData);

promise.then(function (paymentConfigurator) { // needs a slightly better name

    paymentConfigurator.addEventListener("shippingAddressChange", function () { // no need for event
        var newAddress = paymentConfigurator.address;
        console.log(newAddress.street, newAddress.city, newAddress.state, newAddress.zip, newAddress.country);
        // Return back new shipping options
        paymentConfigurator.updateShippingOptions(newShippingOpions);
    });

    return paymentConfigurator.instrumentResponse;
})
.then(function (response) {
    console.log("hurray, valid response from ", response.instrumentName, response.details);
})
.catch(function (err) {
    console.error("oh no, either popping up the configurator dialog or " +
                  "performing the transaction failed", err);
});





// Simpler:

promise.then(function (paymentConfigurator) { // needs a slightly better name
    return paymentConfigurator.instrumentResponse;
})
.then(function (response) {
    console.log("hurray, valid response from ", response.instrumentName, response.details);
})
.catch(function (err) {
    console.error("oh no, either popping up the configurator dialog or " +
                  "performing the transaction failed", err);
});