Re: [Boost-users] How to access a GRAPH property? - simple

Subject: Re: [Boost-users] How to access a GRAPH property? - simple
From: Caligula (caligulaemperorofrome_at_[hidden])
Date: 2010-08-15 03:07:17

Thanks Cedric & Jeremiah,

I tried a bunch of stuff

  template < typename Graph >
    void test_graph_property( Graph & g )
  { 


        //get_property(graph_properties, bobo);
        //g[graph_properties].bobo;
        //g[graph_bundle].bobo;
        //g[bobo];
  
        //get(bobo,g);
        //get(g, graph_properties);
        //cout << g[g].bobo << endl;
  
        //get_property(g.graph_properties, bobo);
        get_property(g, bobo);

  }

But nothing works.
For "get_property(g, bobo);"  I get
  
In function ‘void test_graph_property(Graph&)’:
error: ‘bobo’ was not declared in this scope


The doc pages you refered me to only mention property_maps, as far as I can 
tell.
Maybe I need to declare a property_map such as

       property_map < graph_t, int >::type
          capacity = get(bobo, g);

I would hope that I could avoid this using bundled properties.



Thanks


________________________________
From: Jeremiah Willcock <jewillco_at_[hidden]>
To: boost-users_at_[hidden]
Sent: Sat, August 14, 2010 12:05:25 PM
Subject: Re: [Boost-users] How to access a GRAPH property? - simple

On Fri, 13 Aug 2010, Mike Douglass wrote:

> I have
> 
> struct vertex_properties
> {
>     blah blah
> }
> 
> struct edge_properties
> {
>     blah blah
> }
> 
> struct graph_properties
> {
> 
>   int bobo;
> 
> }
> 
> 
> typedef adjacency_list < vecS, vecS, bidirectionalS,
>         property< vertex_predecessor_t, vertex_t, vertex_properties >,
>         property< edge_reverse_t, edge_t, edge_properties >,
>         graph_properties
>                 > graph_t;
> 
> graph_t g;
> 
> But how can I access bobo?
> 
> g.bobo; does not compile (otherwise compiles OK).

To get the graph property, you can use the get_property() function, documented 
at http://www.boost.org/doc/libs/1_43_0/libs/graph/doc/adjacency_list.html> 
(near the bottom).  Bundled graph properties are new (just added to the trunk in 
the past few weeks); I believe the syntax for those is "g[graph_bundle].bobo".

-- Jeremiah Willcock