Apparently null_property_map is write-only, so it doesn't have a get() function; I hadn't realized that. Please try dummy_property_map (from boost/property_map/property_map.hpp) instead, or if that doesn't work, static_property_map or ref_property_map from the same file.
-- Jeremiah Willcock
With
dp.property("node_id", boost::dummy_property_map());
I get: "error: invalid use of void expression".
with
dp.property("node_id", boost::static_property_mapGraph::vertex_descriptor());
I get: "error: no matching function call to
boost::static_property_map<unsigned int>::static_property_map()"
with
dp.property("node_id",
boost::ref_property_map ::ref_property_map()" Round 3 :) ?
David