Re: [Boost-users] [graph] Bug - add_edge (adjacency_list) does not report if edge already exists as stated in documentation

From: Dmitry Bufistov (dmitry_at_[hidden])
Date: 2008-08-07 06:05:43

Hi Martin,
I think everything is more or less correct here. Changing your graph 
representation to
boost::adjacency_list<boost::setS, boost::vecS, boost::undirectedS>
results in the behavior you expect.

Regards,
Dmitry

Martin Mann wrote:
> 
> Hi,
> 
> I encountered the following problem :
> 
> a successive call with equal parameters u, v, and g of
> 
> ============================================================
> std::pair<edge_descriptor, bool>
>    add_edge(   vertex_descriptor u
>              , vertex_descriptor v
>              , adjacency_list&   g )
> ============================================================
> 
> yields both times "RESULT.second == true".
> 
> But the documentation states, that only in case it is NOT PRESENT it 
> should be true, which is obviously wrong for the second call.
> 

>     
>   //! The definition of a the internal graph representation
> typedef boost::adjacency_list< boost::vecS
>                                , boost::vecS
>                                , boost::undirectedS
>                                , CoreGraph_NodeProperties
>                                , CoreGraph_EdgeProperties
>             >  CoreGraph;
> 
> ============================================================