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.reflect

.reflect() -> Promise<PromiseInspection>

The .reflect method returns a promise that is always successful when this promise is settled. Its fulfillment value is an object that implements the PromiseInspection interface and reflects the resolution of this promise.

Using .reflect() to implement settleAll (wait until all promises in an array are either rejected or fulfilled) functionality

var promises = [getPromise(), getPromise(), getPromise()];
Promise.all(promises.map(function(promise) {
    return promise.reflect();
})).each(function(inspection) {
    if (inspection.isFulfilled()) {
        console.log("A promise in the array was fulfilled with", inspection.value());
    } else {
        console.error("A promise in the array was rejected with", inspection.reason());
    }
});

Using .reflect() to implement settleProps (like settleAll for an object's properties) functionality

var object = {
    first: getPromise1(),
    second: getPromise2()
};
Promise.props(Object.keys(object).reduce(function(newObject, key) {
    newObject[key] = object[key].reflect();
    return newObject;
}, {})).then(function(object) {
    if (object.first.isFulfilled()) {
        console.log("first was fulfilled with", object.first.value());
    } else {
        console.error("first was rejected with", object.first.reason());
    }
})