[boost] range, multi-dimensional

I just posted something on ublas, but I think it may be of more general interest. I have been using boost::range heavily, and find it useful for generic interfaces. I think it is also useful to have a multi-dimensional extension to range. In particular, a 2-d extension would help in creating algorithms that can accept a variety of 2-d structures. For example, range has size, begin, end. range2d would have size1, size2, begin1, begin2. Other useful members might include row, col.