[Boost-users] [BGL] assert( source(* (out_edges(v, undigraph).first), undigraph) == v )

Subject: [Boost-users] [BGL] assert( source(* (out_edges(v, undigraph).first), undigraph) == v )
From: Andreas Fabri (andreas.fabri_at_[hidden])
Date: 2013-05-17 09:38:55

Hello,

When I have an undirected graph, for edge_descriptor
source and target still are defined.

That is stated here:
http://www.boost.org/doc/libs/1_53_0/libs/graph/doc/graph_concepts.html

My question. Is

edge_descriptor ed  = * out_edges(v,undigraph).first;

Is there a requirement for graph implementations
that   source(ed,g) ==  v  ?

best regards,

andreas

-- 
Andreas Fabri, PhD
Chief Officer, GeometryFactory
Editor, The CGAL Project
phone: +33.492.954.912    skype: andreas.fabri