Re: [Boost-users] [Graph] call of overloaded 'target(...)' is ambiguous

/usr/include/boost/graph/edmunds_karp_max_flow.hpp:232: instantiated from 'typename boost::detail::edge_capacity_value::type boost::edmunds_karp_max_flow(Graph&, typename boost::graph_traits<G>::vertex_descriptor, typename boost::graph_traits<G>::vertex_descriptor, const boost::bgl_named_params&) [with Graph = FlowCapacitySQLDiGraph, P = edge_index_property_map, T = boost::edge_residual_capacity_t, R = boost::no_property]' postgraph.cpp:1092: instantiated from here /usr/include/boost/graph/visitors.hpp:176: error: call of overloaded 'target(FlowCapacitySQLDiGraph::edge_descriptor&, const boost::filtered_graph >, boost::keep_all>&)' is ambiguous /usr/include/boost/graph/filtered_graph.hpp:322: note: candidates are: typename boost::filtered_graph_base<G>::vertex_descriptor boost::target(typename boost::filtered_graph_base<G>::edge_descriptor, const boost::filtered_graph_base<Graph>&) [with G = FlowCapacitySQLDiGraph] /usr/include/boost/graph/graph_traits.hpp:154: note: T std::target(std::pair<_ForwardIterator, _ForwardIterator>, const G&) [with T = unsigned int, G = boost::filtered_graph >, boost::keep_all>] make: *** [postgraph.o] Error 1

I'm not sure what version of GCC you're using - I assume it's GCC - but you're ambiguity is coming from the fact that you probably have "using namespace std" somewhere above this point in your code. The file boost/graph/graph_traits.hpp puts a source() and target() function into the standard namespace to provide an overload for a pair of vertex descriptors, which is apparently need for some kinds of edge descriptor. Using graph_traits<G>::edge_descriptor as the parameter type might work. Explicitly calling boost::traget() will also probably work. Andrew Sutton andrew.n.sutton@gmail.com