Re: [Boost-users] [graph]

For a short answer: never.

...

Well, it seemed that sometimes yes.

We'll compromise: sometimes :)

Undoubtedly, above add_vertex function searches vertex by properties and should return descriptor of found vertex. Indeed, it doesn't.

I'm a little bit confused.

I'm a little confused to. The vertex_by_property call will only actually search the vertices if the adjacency_list is using the named_graph framework. If you're not using - and its almost certain that you aren't - the function call evaluates to a no-op. I would say that for the most part - it's just a push_back. Andrew Sutton andrew.n.sutton@gmail.com