template<typename GR>
class lemon::concepts::PathDumper< GR >
A skeleton structure for path dumpers. The path dumpers are the generalization of the paths. The path dumpers can enumerate the arcs of the path wheter in forward or in backward order. In most time these classes are not used directly rather it used to assign a dumped class to a real path type.
The main purpose of this concept is that the shortest path algorithms can enumerate easily the arcs in reverse order. If we would like to give back a real path from these algorithms then we should create a temporarly path object. In LEMON such algorithms gives back a path dumper what can assigned to a real path and the dumpers can be implemented as an adaptor class to the predecessor map.
 Template Parameters

GR  The digraph type in which the path is. 
The paths can be constructed from any path type by a template constructor or a template assignment operator.