[boost] [graph] [iterator] use of iterator_facade in leda_graph.hpp

From: Jens Müller (jens.mueller_at_[hidden])
Date: 2007-03-09 11:22:46

 From leda_graph.hpp:

class out_edge_iterator
       : public iterator_facade<out_edge_iterator,
                                leda::edge,
                                bidirectional_traversal_tag,
                                const leda::edge&,
                                const leda::edge*>

Can someone explain to me the parameter "const leda::edge*"?

http://www.boost.org/libs/iterator/doc/iterator_facade.html#difference 
says the last template parameter is the type for the difference between 
two iterators, how can this be a pointer?

Shouldn't it just be the default std::ptr_diff_t?

Cheers,

Jens