examples from the book

[SVN r11503]

example/binary-method-problem.cpp

@@ -0,0 +1,89 @@
+//=======================================================================
+// Copyright 2001 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee, 
+//
+// This file is part of the Boost Graph Library
+//
+// You should have received a copy of the License Agreement for the
+// Boost Graph Library along with the software; see the file LICENSE.
+// If not, contact Office of Research, Indiana University,
+// Bloomington, IN 47405.
+//
+// Permission to modify the code and to distribute the code is
+// granted, provided the text of this NOTICE is retained, a notice if
+// the code was modified is included with the above COPYRIGHT NOTICE
+// and with the COPYRIGHT NOTICE in the LICENSE file, and that the
+// LICENSE file is distributed with the modified code.
+//
+// LICENSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.
+// By way of example, but not limitation, Licensor MAKES NO
+// REPRESENTATIONS OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
+// PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE COMPONENTS
+// OR DOCUMENTATION WILL NOT INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS
+// OR OTHER RIGHTS.
+//=======================================================================
+#include <string>
+#include <iostream>
+
+class Point
+{
+public:
+  virtual bool equal(const Point * p) const = 0;
+};
+
+class ColorPoint:public Point
+{
+public:
+  ColorPoint(float x, float y, std::string c):x(x), y(y), color(c)
+  {
+  }
+  virtual bool equal(const ColorPoint * p) const
+  {
+    return color == p->color && x == p->x && y == p->y;
+  }
+protected:
+  float x, y;
+  std::string color;
+};
+
+class ColorPoint2:public Point
+{
+public:
+  ColorPoint2(float x, float y, std::string s):x(x), y(y), color(s)
+  {
+  }
+  virtual bool equal(const Point * p) const
+  {
+    const ColorPoint2 *cp = dynamic_cast < const ColorPoint2 * >(p);
+      return color == cp->color && x == cp->x && y == cp->y;
+  }
+protected:
+  float x, y;
+  std::string color;
+};
+
+void
+print_equal(const Point * a, const Point * b)
+{
+  std::cout << std::boolalpha << a->equal(b) << std::endl;
+}
+
+template < typename PointType > void
+print_equal2(const PointType * a, const PointType * b)
+{
+  std::cout << std::boolalpha << a->equal(b) << std::endl;
+}
+
+
+int
+main()
+{
+  Point *p = new ColorPoint2(0.0, 0.0, "blue");
+  Point *q = new ColorPoint2(0.0, 0.0, "green");
+  print_equal(p, q);
+  ColorPoint *a = new ColorPoint(0.0, 0.0, "blue");
+  ColorPoint *b = new ColorPoint(0.0, 0.0, "green");
+  print_equal2(a, b);
+
+
+  return 0;
+}