Thanks a lot, even though I read half of the BGL book I didnt get this difference.
I cant say Im good with techniques like that.

Best,
Tasos
  

----------------------------------------------------------------------

Message: 1
Date: Thu, 31 Jan 2013 11:12:29 -0500 (EST)
From: Jeremiah Willcock <jewillco@osl.iu.edu>
To: boost-users@lists.boost.org
Subject: Re: [Boost-users] [Graph] visitor dijkstra_shortest_paths
Message-ID: <alpine.LRH.2.03.1301311111140.64740@cs.indiana.edu>
Content-Type: text/plain; charset="iso-8859-1"; Format="flowed"

On Thu, 31 Jan 2013, The Maschine wrote:

>
> Hi all,
>
>
> Can someone explain me why I get an error with the first one and not the second?
>
>
> 1) (error)?boost::dijkstra_shortest_paths(m_ugraph,*vertex_iterator_begin,? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
> ?boost::distance_map(boost::make_iterator_property_map(dist_map.begin(), boost::get(boost::vertex_index,
> m_ugraph))),
>
> boost::visitor(dijkstra_vis( *vertex_iterator_begin, superStorage ) ));

The syntax for named parameters in Boost.Graph requires periods, so all
named arguments show up as a single argument to C++.

> 2) (good)?boost::dijkstra_shortest_paths(m_ugraph,*vertex_iterator_begin,? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
> ?boost::distance_map(boost::make_iterator_property_map(dist_map.begin(), boost::get(boost::vertex_index,
> m_ugraph))).visitor(dijkstra_vis( *vertex_iterator_begin, superStorage ))?);
>
>
>
> Why I need to "." the visitor on the distance_map?

That's how it was implemented (before Boost.Parameter or variadic
templates existed).

>
>
> BFS is ok with it:
>
> (good) boost::breadth_first_search(m_ugraph, *vertex_iterator_begin , boost::visitor(bfs_vis(
> *vertex_iterator_begin, superStorage ) ));

You only have one named argument there; if you had more, you would need to
use a period between those as well.

-- Jeremiah Willcock