When you are getting ready to move homes, purging a closet is a priority. Our suggestion with our clients always is to purge on the front end before you start packing up a full closet. Purge. You don't want to necessarily unpack things that you don't want, nor do you want to take up prime real estate in the new house with items you don't want.
If for some reason you can't purge on the front end, you obviously can purge on the back end. But I will tell you that purging and moving go hand in hand, that is how you're going to set up a space with function and beauty.