[hawick] Support passing std::reference_wrapper to boost::hawick_circuits

Reported as ldionne/hawick_circuits#1.

README.md

@@ -1,4 +1,4 @@
-Boost Graph Library
+Boost Graph Library  [![Build Status](https://travis-ci.org/boostorg/graph.svg?branch=develop)](https://travis-ci.org/boostorg/graph)
 ===================
 
 A generic interface for traversing graphs, using C++ templates.
@@ -7,9 +7,14 @@ The full documentation is available on [boost.org](http://www.boost.org/doc/libs
 
 ## Support, bugs and feature requests ##
 
-Bugs and feature requests can be reported through the [Trac issue tracker](https://svn.boost.org/trac/boost/query?component=graph&desc=1&order=id)
-(see [open issues](https://svn.boost.org/trac/boost/query?status=!closed&component=graph&desc=1&order=id) and
-[closed issues](https://svn.boost.org/trac/boost/query?status=closed&component=graph&col=id&col=summary&col=status&col=owner&col=type&col=milestone&col=version&desc=1&order=id)). [Here](http://lists.boost.org/Archives/boost/2015/04/221780.php) is why Trac is still in use.
+Bugs and feature requests can be reported through the [Github issue page](https://github.com/boostorg/graph/issues).
+
+See also:
+
+* [Current open issues](https://github.com/boostorg/graph/issues)
+* [Closed issues](https://github.com/boostorg/graph/issues?utf8=%E2%9C%93&q=is%3Aissue+is%3Aclosed)
+* Old issues still open on [Trac](https://svn.boost.org/trac/boost/query?status=!closed&component=graph&desc=1&order=id)
+* Closed issues on [Trac](https://svn.boost.org/trac/boost/query?status=closed&component=graph&col=id&col=summary&col=status&col=owner&col=type&col=milestone&col=version&desc=1&order=id)).
 
 You can submit your changes through a [pull request](https://github.com/boostorg/graph/pulls). One of the maintainers will take a look (remember that it can take some time).
 
@@ -18,6 +23,12 @@ There is no mailing-list specific to Boost Graph, although you can use the gener
 
 ## Development ##
 
+|                  |  Master  |   Develop   |
+|------------------|----------|-------------|
+| Travis           | [![Build Status](https://travis-ci.org/boostorg/graph.svg?branch=master)](https://travis-ci.org/boostorg/graph)  |  [![Build Status](https://travis-ci.org/boostorg/graph.svg)](https://travis-ci.org/boostorg/graph) |
+| Appveyor         | [![Build status](https://ci.appveyor.com/api/projects/status/78gegk21tc1g3v8d/branch/master?svg=true)](https://ci.appveyor.com/project/jzmaddock/graph/branch/master) | [![Build status](https://ci.appveyor.com/api/projects/status/78gegk21tc1g3v8d/branch/develop?svg=true)](https://ci.appveyor.com/project/jzmaddock/graph/branch/develop)  |
+
+
 Clone the whole boost project, which includes the individual Boost projects as submodules ([see boost+git doc](https://github.com/boostorg/boost/wiki/Getting-Started)):
 
     git clone https://github.com/boostorg/boost

doc/hawick_circuits.html

@@ -49,6 +49,10 @@ edges are not desired.</p>
 
   <p>For example, if a circuit <code>u -&gt; v -&gt; w -&gt; u</code> exists in the graph, the
   visitor will be called with a sequence consisting of <code>(u, v, w)</code>.</p>
+
+  Note that if <code>visitor</code> is a <code>std::reference_wrapper</code>,
+  it will be unwrapped before the <code>.cycle</code> method being called on it.
+  This allows passing a visitor that shouldn't be copied.
 </blockquote>
 
 <p><strong>IN:</strong> <code>VertexIndexMap const&amp; vim = get(vertex_index, graph)</code></p>

include/boost/graph/edmunds_karp_max_flow.hpp

@@ -8,11 +8,11 @@
 #ifndef BOOST_DEPRECATED_INCLUDE_EDMONDS_KARP_MAX_FLOW_HPP
 #define BOOST_DEPRECATED_INCLUDE_EDMONDS_KARP_MAX_FLOW_HPP
 
-#if defined(_MSC_VER) || defined(__BORLANDC__) || defined(__DMC__)
+#if defined(_MSC_VER) || defined(__BORLANDC__) && !defined(__clang__) || defined(__DMC__)
 #pragma message( \
     "Warning: This header is deprecated. Please use: boost/graph/edmonds_karp_max_flow.hpp")
 #elif defined(__GNUC__) || defined(__HP_aCC) || defined(__SUNPRO_CC) \
-    || defined(__IBMCPP__)
+    || defined(__IBMCPP__) || defined(__BORLANDC__)
 #warning \
     "This header is deprecated. Please use: boost/graph/edmonds_karp_max_flow.hpp"
 #endif

include/boost/graph/graph_concepts.hpp

@@ -38,7 +38,7 @@ namespace boost
 // It is needed in order to allow us to write using boost::vertices as
 // needed for ADL when using vector_as_graph below.
 #if !defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP) \
-    && !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
+    && !BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x564))
 #define BOOST_VECTOR_AS_GRAPH_GRAPH_ADL_HACK
 #endif
 

include/boost/graph/hawick_circuits.hpp

@@ -21,6 +21,7 @@
 #include <boost/tuple/tuple.hpp> // for boost::tie
 #include <boost/type_traits/remove_reference.hpp>
 #include <boost/utility/result_of.hpp>
+#include <functional> // for std::reference_wrapper
 #include <set>
 #include <utility> // for std::pair
 #include <vector>
@@ -89,6 +90,18 @@ namespace hawick_circuits_detail
         return std::find(boost::begin(c), boost::end(c), v) != boost::end(c);
     }
 
+    template < typename T >
+    struct unwrap_reference_wrapper {
+        typedef T type;
+    };
+
+#if __cplusplus >= 201103L
+    template < typename T >
+    struct unwrap_reference_wrapper<std::reference_wrapper<T> > {
+        typedef T& type;
+    };
+#endif
+
     /*!
      * @internal
      * Algorithm finding all the cycles starting from a given vertex.
@@ -301,8 +314,9 @@ namespace hawick_circuits_detail
 
         typedef std::vector< Vertex > Stack;
         typedef std::vector< std::vector< Vertex > > ClosedMatrix;
+        typedef typename unwrap_reference_wrapper<Visitor>::type VisitorNoRef;
 
-        typedef hawick_circuits_from< Graph, Visitor, VertexIndexMap, Stack,
+        typedef hawick_circuits_from< Graph, VisitorNoRef, VertexIndexMap, Stack,
             ClosedMatrix, GetAdjacentVertices >
             SubAlgorithm;
 

include/boost/graph/random.hpp

@@ -38,7 +38,7 @@ typename graph_traits< Graph >::vertex_descriptor random_vertex(
 {
     if (num_vertices(g) > 1)
     {
-#if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x581))
+#if BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x581))
         std::size_t n = std::random(num_vertices(g));
 #else
         uniform_int<> distrib(0, num_vertices(g) - 1);
@@ -59,7 +59,7 @@ typename graph_traits< Graph >::edge_descriptor random_edge(
 {
     if (num_edges(g) > 1)
     {
-#if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x581))
+#if BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x581))
         typename graph_traits< Graph >::edges_size_type n
             = std::random(num_edges(g));
 #else

test/dijkstra_no_color_map_compare.cpp

@@ -10,6 +10,7 @@
 #include <iostream>
 #include <map>
 #include <vector>
+#include <ctime>
 #include <boost/config.hpp>
 
 #ifdef BOOST_MSVC
@@ -80,7 +81,7 @@ int main(int argc, char* argv[])
 
     int vertices_to_create = 10;
     int edges_to_create = 500;
-    std::size_t random_seed = time(0);
+    std::size_t random_seed = std::time(0);
 
     if (argc > 1)
     {

test/grid_graph_test.cpp

@@ -10,6 +10,7 @@
 #include <fstream>
 #include <iostream>
 #include <set>
+#include <ctime>
 
 #include <boost/foreach.hpp>
 #include <boost/lexical_cast.hpp>
@@ -224,7 +225,7 @@ template < unsigned int Dims > void do_test(minstd_rand& generator)
 int main(int argc, char* argv[])
 {
 
-    std::size_t random_seed = time(0);
+    std::size_t random_seed = std::time(0);
 
     if (argc > 1)
     {

test/hawick_circuits.cpp

@@ -6,6 +6,8 @@
 
 #include "cycle_test.hpp"
 #include <boost/graph/hawick_circuits.hpp>
+#include <cstddef>
+#include <functional>
 #include <iostream>
 
 struct call_hawick_circuits
@@ -26,6 +28,20 @@ struct call_hawick_unique_circuits
     }
 };
 
+struct not_copyable
+{
+    not_copyable() { }
+
+    template < typename Path, typename Graph >
+    void cycle(Path const&, Graph const&)
+    {
+
+    }
+
+private:
+    not_copyable(not_copyable const&);
+};
+
 int main()
 {
     std::cout << "---------hawick_circuits---------\n";
@@ -33,4 +49,24 @@ int main()
 
     std::cout << "\n\n---------hawick_unique_circuits---------\n";
     cycle_test(call_hawick_unique_circuits());
+
+    // Make sure we can pass a reference_wrapper to the algorithm.
+#if __cplusplus >= 201103L
+    {
+        typedef boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS> Graph;
+        typedef std::pair<std::size_t, std::size_t> Pair;
+        Pair edges[3] = {
+            Pair(0, 1), // a->b
+            Pair(1, 2), // b->c
+            Pair(2, 0), // c->a
+        };
+
+        Graph G(3);
+        for (int i = 0; i < 3; ++i)
+            add_edge(edges[i].first, edges[i].second, G);
+
+        not_copyable visitor;
+        boost::hawick_circuits(G, std::ref(visitor));
+    }
+#endif // >= C++11
 }

test/incremental_components_test.cpp

@@ -10,6 +10,7 @@
 #include <iostream>
 #include <map>
 #include <set>
+#include <ctime>
 
 #include <boost/foreach.hpp>
 #include <boost/graph/adjacency_list.hpp>
@@ -127,7 +128,7 @@ template < typename Graph > void test_graph(const Graph& graph)
 int main(int argc, char* argv[])
 {
     std::size_t vertices_to_generate = 100, edges_to_generate = 50,
-                random_seed = time(0);
+                random_seed = std::time(0);
 
     // Parse command-line arguments
 

test/mcgregor_subgraphs_test.cpp

@@ -12,6 +12,7 @@
 #include <fstream>
 #include <sstream>
 #include <vector>
+#include <ctime>
 
 #include <boost/lexical_cast.hpp>
 #include <boost/random.hpp>
@@ -311,7 +312,7 @@ int main(int argc, char* argv[])
 {
     int vertices_to_create = 10;
     int max_edges_per_vertex = 2;
-    std::size_t random_seed = time(0);
+    std::size_t random_seed = std::time(0);
 
     if (argc > 1)
     {

test/metric_tsp_approx.cpp

@@ -90,7 +90,7 @@ void testScalability(unsigned numpts)
     typedef set< simple_point< double >, cmpPnt< double > > PointSet;
     typedef vector< Vertex > Container;
 
-    boost::mt19937 rng(time(0));
+    boost::mt19937 rng(std::time(0));
     uniform_real<> range(0.01, (numpts * 2));
     variate_generator< boost::mt19937&, uniform_real<> > pnt_gen(rng, range);