Use conforming is_class for EDG compilers

Make is_enum work for class types which are convertible to anything at
all (on many compilers).

smart_ptr library workarounds for __MWERKS__ (must use member function
pointer for unspecified_bool_type).


[SVN r20244]

include/boost/type_traits/config.hpp

@@ -25,7 +25,7 @@
 #   define BOOST_TT_DECL /**/
 #endif
 
-# if (defined(__MWERKS__) && __MWERKS__ >= 0x3000) || (defined(BOOST_MSVC) && (BOOST_MSVC > 1301)) || defined(BOOST_NO_COMPILER_CONFIG)
+# if (defined(__MWERKS__) && __MWERKS__ >= 0x3000) || (defined(BOOST_MSVC) && (BOOST_MSVC > 1301)) || defined(__EDG_VERSION__) || defined(BOOST_NO_COMPILER_CONFIG)
 #   define BOOST_TT_HAS_CONFORMING_IS_CLASS_IMPLEMENTATION
 #endif
 

include/boost/type_traits/is_class.hpp

@@ -1,5 +1,5 @@
 //  (C) Copyright Dave Abrahams, Steve Cleary, Beman Dawes, Howard
-//  Hinnant & John Maddock 2000-2002.  Permission to copy, use,
+//  Hinnant & John Maddock 2000-2003.  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
@@ -17,6 +17,10 @@
 
 #ifdef BOOST_TT_HAS_CONFORMING_IS_CLASS_IMPLEMENTATION
 #   include "boost/type_traits/detail/yes_no_type.hpp"
+#   ifdef __EDG_VERSION__
+#       include "boost/type_traits/is_const.hpp"
+#       include "boost/type_traits/is_volatile.hpp"
+#   endif 
 #else
 #   include "boost/type_traits/is_scalar.hpp"
 #   include "boost/type_traits/is_array.hpp"
@@ -59,6 +63,26 @@ struct is_class_impl
         );
 };
 
+# ifdef __EDG_VERSION__
+template <typename T>
+struct is_class_impl<T const>
+  : is_class_impl<T>
+{
+};
+
+template <typename T>
+struct is_class_impl<T volatile>
+  : is_class_impl<T>
+{
+};
+
+template <typename T>
+struct is_class_impl<T const volatile>
+  : is_class_impl<T>
+{
+};
+# endif
+
 #else
 
 template <typename T>

include/boost/type_traits/is_enum.hpp

@@ -20,10 +20,6 @@
 #endif
 #include "boost/type_traits/config.hpp"
 
-#ifdef BOOST_TT_HAS_CONFORMING_IS_CLASS_IMPLEMENTATION
-#   include "boost/type_traits/is_class.hpp"
-#endif
-
 // should be the last #include
 #include "boost/type_traits/detail/bool_trait_def.hpp"
 
@@ -32,7 +28,29 @@ namespace boost {
 #if !(defined(__BORLANDC__) && (__BORLANDC__ <= 0x551))
 
 namespace detail {
-  
+
+template <typename T>
+struct is_class_or_union
+{
+# if BOOST_WORKAROUND(BOOST_MSVC, == 1200) // we simply can't detect it this way.
+    BOOST_STATIC_CONSTANT(bool, value = false);
+# else
+    template <class U> static ::boost::type_traits::yes_type is_class_or_union_tester(void(U::*)(void));
+    
+#  if BOOST_WORKAROUND(BOOST_MSVC, == 1300)                 \
+    || BOOST_WORKAROUND(__MWERKS__, <= 0x3000) // no SFINAE
+    static ::boost::type_traits::no_type is_class_or_union_tester(...);
+    BOOST_STATIC_CONSTANT(
+        bool, value = sizeof(is_class_or_union_tester(0)) == sizeof(::boost::type_traits::yes_type));
+#  else
+    template <class U>
+    static ::boost::type_traits::no_type is_class_or_union_tester(...);
+    BOOST_STATIC_CONSTANT(
+        bool, value = sizeof(is_class_or_union_tester<T>(0)) == sizeof(::boost::type_traits::yes_type));
+#  endif 
+# endif 
+};
+
 struct int_convertible
 {
     int_convertible(int);
@@ -63,20 +81,7 @@ template <typename T> struct is_enum_impl
    typedef ::boost::add_reference<T> ar_t;
    typedef typename ar_t::type r_type;
        
-#if defined(BOOST_TT_HAS_CONFORMING_IS_CLASS_IMPLEMENTATION)
-   BOOST_STATIC_CONSTANT(bool, selector =
-      (::boost::type_traits::ice_or<
-           ::boost::is_arithmetic<T>::value
-         , ::boost::is_reference<T>::value
-       // We MUST do this on conforming compilers in order to
-       // correctly deduce that noncopyable types are not enums (dwa
-       // 2002/04/15)...
-       // strictly speaking is_convertible should work with non-copyable
-       // types rendering this fix unnecessary - unfortunately this is not
-       // the case for all compilers yet (JM 2003/04/16)...
-         , ::boost::is_class<T>::value
-      >::value));
-#elif defined __GNUC__ 
+#if defined __GNUC__ 
    BOOST_STATIC_CONSTANT(bool, selector =
       (::boost::type_traits::ice_or<
            ::boost::is_arithmetic<T>::value
@@ -88,6 +93,7 @@ template <typename T> struct is_enum_impl
       (::boost::type_traits::ice_or<
            ::boost::is_arithmetic<T>::value
          , ::boost::is_reference<T>::value
+         , is_class_or_union<T>::value
        // However, not doing this on non-conforming compilers prevents
        // a dependency recursion.
       >::value));
@@ -100,6 +106,7 @@ template <typename T> struct is_enum_impl
 #else
     typedef ::boost::detail::is_enum_helper<selector> se_t;
 #endif
+
     typedef typename se_t::template type<r_type> helper;
     BOOST_STATIC_CONSTANT(bool, value = helper::value);
 };

test/Jamfile

@@ -81,6 +81,7 @@ test-suite type_traits :
 [ type-traits-run tricky_add_pointer_test.cpp ]
 [ type-traits-run tricky_function_type_test.cpp ]
 [ type-traits-run tricky_incomplete_type_test.cpp ]
+[ type-traits-run tricky_is_enum_test.cpp ]
 [ type-traits-run tricky_partial_spec_test.cpp ]
 [ type-traits-run type_with_alignment_test.cpp ]
 

test/tricky_is_enum_test.cpp

@@ -0,0 +1,27 @@
+
+//  (C) Copyright Dave Abrahams 2003. Use, modification and distribution is
+//  subject to 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)
+
+#include "test.hpp"
+#include "check_integral_constant.hpp"
+#include TYPE_TRAITS(is_enum)
+
+struct convertible_to_anything
+{
+	template<typename T> operator T() { return 0; }
+};
+
+
+TT_TEST_BEGIN(is_enum)
+
+BOOST_CHECK_INTEGRAL_CONSTANT(::tt::is_enum<convertible_to_anything>::value, false);
+
+TT_TEST_END
+
+
+
+
+
+
+