Thank you for this info. However, it is not used (!) in -for example-
connected_componets of the BGL which means - please, I have to insist on this
point - that connecetd_components will not work if my datastructure does not
support the discussed requirement on out_edges. Is there any reason why
adjacency_iterator is not used in some cases by BGL algorithms but instead
out_edges together with the target function?
The adjacency_iterator hides the edge traversal, which are used by a number of algorithm visitors.
What do you mean "doesn't work?". You have to be more explicit.