[Boost-users] hash function for edge_descriptor

8 Aug 2005

      Hello there,

I was trying to create hash_maps with vertex_descriptors and
edge_descriptors.

The first one was easy with vertex_descriptors being just void*'s, and there
is even an example in the boost detail namespace (although it's not
activated using gcc):

template <>
struct hash< void* >
{
  std::size_t
  operator()(void* v) const { return (std::size_t)v; }
}

But the edge_descriptors give me some serious headache. How could I create a
hash function for them? Is using the source and target a good idea in graphs
where there could easily be more than one edge between two vertices? Or is
there a great method I cannot come up with?

I hope that somebody can help me out here :)

Thanks,
Wolfram Koska