New: richcmp.html, richcmp1.cpp, richcmp2.cpp, richcmp3.cpp.

Still needs more testing. richcmp1.cpp does not compile under windows.


[SVN r10656]

example/richcmp2.cpp

@@ -0,0 +1,61 @@
+// Example by Ralf W. Grosse-Kunstleve
+// This example shows how to use rich comparisons for a type that
+// does not support all six operators (<, <=, ==, !=, >, >=).
+// To keep the example simple, we are using a "code" type does
+// not really require rich comparisons. __cmp__ would be sufficient.
+// However, with a more complicated type the main point of this
+// example would be in danger of getting lost.
+
+#include <boost/python/class_builder.hpp>
+
+namespace {
+
+  // suppose operator< and operator> are not meaningful for code
+  class code {
+    public:
+      code(int c = 0) : m_code(c) {}
+      inline friend bool operator==(const code& lhs, const code& rhs) {
+        return lhs.m_code == rhs.m_code;
+      }
+      inline friend bool operator!=(const code& lhs, const code& rhs) {
+        return lhs.m_code != rhs.m_code;
+      }
+    private:
+      int m_code;
+  };
+
+  boost::python::ref
+  NotImplemented(const code&, const code&) {
+    return
+    boost::python::ref(Py_NotImplemented, boost::python::ref::increment_count);
+  }
+}
+
+namespace {
+
+  void init_module(boost::python::module_builder& this_module)
+  {
+    boost::python::class_builder<code> py_code(this_module, "code");
+
+    py_code.def(boost::python::constructor<>());
+    py_code.def(boost::python::constructor<int>());
+    py_code.def(boost::python::operators<(  boost::python::op_eq
+                                          | boost::python::op_ne)>());
+    py_code.def(NotImplemented, "__lt__");
+    py_code.def(NotImplemented, "__le__");
+    py_code.def(NotImplemented, "__gt__");
+    py_code.def(NotImplemented, "__ge__");
+  }
+
+} // namespace <anonymous>
+
+BOOST_PYTHON_MODULE_INIT(richcmp2)
+{
+  try {
+    boost::python::module_builder this_module("richcmp2");
+    // The actual work is done in separate function in order
+    // to suppress a bogus VC60 warning.
+    init_module(this_module);
+  }
+  catch(...){boost::python::handle_exception();}
+}