BGL write_graphviz and VertexList type

From: Solomon Gibbs (solomon.gibbs_at_[hidden])
Date: 2003-08-11 19:02:20

Hello,

I've been trying to use the write_graphviz function in BGL, and I've noticed 
that it appears to be sensitive to the type of VertexList used in the graph.

adjacency_lists using a boost::vecS produce vertex indices in integer form 
like:
graph G {
   0[label="0"];
   1[label="1"];
   0--1 [label="2.8"];
}

but the same code backed by boost::listS seems to not dereference completely:
graph G {
   0x80545f0[label="10"];
   0x8054608[label="11"];
   0x80545f0--0x8054608 [label="2.8"];
}
dot doesn't like this.

I notice that write_graphviz dereferences 
boost::graph_traits<Graph>::vertex_iterator to print the vertex.
Are the listS and vecS *operators different somehow?

The vector backed adjacency_list also seems to be automagically setting the 
vertex_index property to the actual index of the vertex in the storage vector 
instead of the value given in add_vertex().

My question is:  Is this the expected behavior for these classes or some 
problem I've managed to create on my own?

Thanks,

Solomon