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diff --git a/src/boost/libs/flyweight/example/key_value.cpp b/src/boost/libs/flyweight/example/key_value.cpp
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+/* Boost.Flyweight example of use of key-value flyweights.
+ *
+ * Copyright 2006-2008 Joaquin M Lopez Munoz.
+ * Distributed under the Boost Software License, Version 1.0.
+ * (See accompanying file LICENSE_1_0.txt or copy at
+ * http://www.boost.org/LICENSE_1_0.txt)
+ *
+ * See http://www.boost.org/libs/flyweight for library home page.
+ */
+
+#include <boost/array.hpp>
+#include <boost/flyweight.hpp>
+#include <boost/flyweight/key_value.hpp>
+#include <cstdlib>
+#include <iostream>
+#include <string>
+#include <vector>
+
+using namespace boost::flyweights;
+
+/* A class simulating a texture resource loaded from file */
+
+class texture
+{
+public:
+  texture(const std::string& filename):filename(filename)
+  {
+    std::cout<<"loaded "<<filename<<" file"<<std::endl;
+  }
+
+  texture(const texture& x):filename(x.filename)
+  {
+    std::cout<<"texture["<<filename<<"] copied"<<std::endl;
+  }
+
+  ~texture()
+  {
+    std::cout<<"unloaded "<<filename<<std::endl;
+  }
+
+  const std::string& get_filename()const{return filename;}
+
+  // rest of the interface
+
+private:
+  std::string filename;
+};
+
+/* key extractor of filename strings from textures */
+
+struct texture_filename_extractor
+{
+  const std::string& operator()(const texture& x)const
+  {
+    return x.get_filename();
+  }
+};
+
+/* texture flyweight */
+
+typedef flyweight<
+  key_value<std::string,texture,texture_filename_extractor>
+> texture_flyweight;
+
+int main()
+{
+  /* texture filenames */
+
+  const char* texture_filenames[]={
+    "grass.texture","sand.texture","water.texture","wood.texture",
+    "granite.texture","cotton.texture","concrete.texture","carpet.texture"
+  };
+  const int num_texture_filenames=
+    sizeof(texture_filenames)/sizeof(texture_filenames[0]);
+
+  /* create a massive vector of textures */
+
+  std::cout<<"creating flyweights...\n"<<std::endl;
+
+  std::vector<texture_flyweight> textures;
+  for(int i=0;i<50000;++i){
+    textures.push_back(
+      texture_flyweight(texture_filenames[std::rand()%num_texture_filenames]));
+  }
+
+  /* Just for the sake of making use of the key extractor,
+   * assign some flyweights with texture objects rather than strings.
+   */
+
+  for(int j=0;j<50000;++j){
+    textures.push_back(
+      texture_flyweight(
+        textures[std::rand()%textures.size()].get()));
+  }
+
+  std::cout<<"\n"<<textures.size()<<" flyweights created\n"<<std::endl;
+
+  return 0;
+}