For the most part, mulch is not the best use for compost. The main reason for this is due to the finished state of it. Instead of resembling mulch, the finished product of compost is going to resemble soil. If you have ever laid mulch than you know that this will not work the best. With that being said, if you just wanted to compost leaves this could do the trick. And, it is even better when the leaves are partially rotted.