[Boost-users] [BGL] destroying a subgraph

Hello, I'm trying to implement the IncidenceGraph concept for an non-BGL undirected graph like datastructure. Following the boost documentation the target function used with edges from out_edges(u,g) must give vertices != u. Can somebody please explain me why this requirement is in BGL! I think it can make the adaption very difficult as it requieres to artificially orientate undirected edges for each call to out_edges. Any help would be much appreciated! Thanks in advance, Chris -- GMX FreeDSL Komplettanschluss mit DSL 6.000 Flatrate und Telefonanschluss für nur 17,95 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02