[Boost-users] [BGL] property tag classes and "num"

From: Jens Müller (jens.mueller_at_[hidden])
Date: 2006-05-29 06:20:51

From
<http://www.boost.org/libs/graph/doc/using_adjacency_list.html#sec:adjacency-list-properties>:

| Custom Edge Properties
|
| Creating your own property types and properties is easy; just define a
| tag class for your new property. The property tag class will need to
| define num with a unique integer ID, and kind which should be either
| edge_property_tag, vertex_property_tag, or graph_property_tag.
|
| struct flow_t {
|   typedef edge_property_tag kind;
| };
|
| struct capacity_t {
|   typedef edge_property_tag kind;
| };

It works with structs like this.

Am I missing something, or where is "num"?