[Boost-users] Iterator to wrap around ends of the container. Does it exist?

Hi, Just wondered if there was anything in Boost so that when an iterator is incremented, if it's at the last element it goes to the begin() of the container. And for decrement if at the beginning it would refer to one before end(). The sequence would have to be finite, so just selecting a different logical begin and end really. I'm looking to solve this using some kind of new iterator (iterator adaptor) rather than a change of container. If there anything in Boost for this? Thanks, Pete