> once you adopt Promises a large portion of your code will have to be tailored to use it.
This isn't a necessity, since you can create a function which both returns a Promise and accepts a callback. Most Promise libraries make this easy to support, which makes it easy to introduce Promises into projects that already use callbacks, and vice-versa.
This isn't a necessity, since you can create a function which both returns a Promise and accepts a callback. Most Promise libraries make this easy to support, which makes it easy to introduce Promises into projects that already use callbacks, and vice-versa.