From 406b57c444ceefa00d590cddf5f453585def22a5 Mon Sep 17 00:00:00 2001
From: John Maddock <john@johnmaddock.co.uk>
Date: Sat, 26 Oct 2002 11:35:02 +0000
Subject: [PATCH] Added is_polymorphic.

[SVN r15985]
---
 include/boost/type_traits/is_polymorphic.hpp | 83 ++++++++++++++++++++
 test/is_polymorphic_test.cpp                 | 52 ++++++++++++
 2 files changed, 135 insertions(+)
 create mode 100644 include/boost/type_traits/is_polymorphic.hpp
 create mode 100644 test/is_polymorphic_test.cpp

diff --git a/include/boost/type_traits/is_polymorphic.hpp b/include/boost/type_traits/is_polymorphic.hpp
new file mode 100644
index 0000000..90f6f06
--- /dev/null
+++ b/include/boost/type_traits/is_polymorphic.hpp
@@ -0,0 +1,83 @@
+//  (C) Copyright John Maddock 2000. Permission to copy, use, modify, sell and   
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+#ifndef BOOST_TT_IS_POLYMORPHIC_HPP
+#define BOOST_TT_IS_POLYMORPHIC_HPP
+
+#include <boost/type_traits/is_class.hpp>
+// should be the last #include
+#include "boost/type_traits/detail/bool_trait_def.hpp"
+
+namespace boost{
+namespace detail{
+
+template <class T>
+struct is_polymorphic_imp1
+{
+   struct d1 : public T
+   {
+      d1();
+      ~d1();
+      char padding[256];
+   };
+   struct d2 : public T
+   {
+      d2();
+      virtual ~d2();
+#ifndef BOOST_MSVC
+      // for some reason this messes up VC++ when T has virtual bases:
+      virtual void foo();
+#endif
+      char padding[256];
+   };
+   BOOST_STATIC_CONSTANT(bool, value = (sizeof(d2) == sizeof(d1)));
+};
+
+template <class T>
+struct is_polymorphic_imp2
+{
+   BOOST_STATIC_CONSTANT(bool, value = false);
+};
+
+template <bool is_class>
+struct is_polymorphic_selector
+{
+   template <class T>
+   struct rebind
+   {
+      typedef is_polymorphic_imp2<T> type;
+   };
+};
+
+template <>
+struct is_polymorphic_selector<true>
+{
+   template <class T>
+   struct rebind
+   {
+      typedef is_polymorphic_imp1<T> type;
+   };
+};
+
+template <class T>
+struct is_polymorphic_imp
+{
+   typedef is_polymorphic_selector< ::boost::is_class<T>::value> selector;
+   typedef typename selector::template rebind<T> binder;
+   typedef typename binder::type imp_type;
+   BOOST_STATIC_CONSTANT(bool, value = imp_type::value);
+};
+
+} // namespace detail
+
+BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_polymorphic,T,::boost::detail::is_polymorphic_imp<T>::value)
+
+} // namespace boost
+
+#include "boost/type_traits/detail/bool_trait_undef.hpp"
+
+#endif
+
+
diff --git a/test/is_polymorphic_test.cpp b/test/is_polymorphic_test.cpp
new file mode 100644
index 0000000..8f5e089
--- /dev/null
+++ b/test/is_polymorphic_test.cpp
@@ -0,0 +1,52 @@
+
+//  (C) Copyright John Maddock 2000. Permission to copy, use, modify, sell and   
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+#include "test.hpp"
+#include "check_integral_constant.hpp"
+#include TYPE_TRAITS(is_polymorphic)
+
+TT_TEST_BEGIN(is_polymorphic)
+
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<int>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<const int>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<volatile int>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<int*>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<int* const>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<int[2]>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<int&>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<mf4>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<f1>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<enum_UDT>::value, false);
+
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<UDT>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<UDT const>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<UDT volatile>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<empty_UDT>::value, false);
+
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<UDT*>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<UDT[2]>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<UDT&>::value, false);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<void>::value, false);
+
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<VB>::value, true);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<VD>::value, true);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<test_abc1>::value, true);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<test_abc2>::value, true);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<std::iostream>::value, true);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<std::ios_base>::value, true);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<std::basic_streambuf<char> >::value, true);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<std::basic_ios<char> >::value, true);
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_polymorphic<std::basic_istream<char> >::value, true);
+
+TT_TEST_END
+
+
+
+
+
+
+
+