Hi,<br />I need to use the topological_sort BGL algorithm.<br />This algorithm needs either that the graph has an internal vertex index property or
that you provide a property map for it.<br />I'd like to perform conditional compilation, so that I only build and provide the vertex index property
map when it's needed,<br />and the internal index property of the graph when it has it.<br />For example, for an adjacency_list with vecS for
VertexList,<br />the property already exists in the graph and I wouldn't like to provide a property map for it.<br />But if I choose listS for
VertexList, there isn't such internal property and I need to provide the property map.<br />As I don't know what Graph implementation my template
will be provided,<br />I need to find a way to know at compile time if that graph has the internal index property or not.<br />Is there any
(documented?) way to do it?<br />This is the concrete information I need right now, but, if possible,<br />I'd like to know how to find out if the
graph has any concrete internal property, and not only the index one.<br />Thanks,<br /><br />Juan