Depth first search with Boost R-Tree

Is it possible to do a depth-first search / iteration over a Boost R-Tree?

There is a related question on SO here: C++: Boost Library and DFS in a R-Tree

There seems to be a DFS API which did not exist at the time the other question was asked: http://ift.tt/2vujnIV

Though I'm puzzled if and how this would work with a Boost R-Tree.