-// (C) Copyright 2002-2008, Fernando Luis Cacciola Carballal.\r
-//\r
-// Distributed under the Boost Software License, Version 1.0. (See\r
-// accompanying file LICENSE_1_0.txt or copy at\r
-// http://www.boost.org/LICENSE_1_0.txt)\r
-//\r
-// 21 Ago 2002 (Created) Fernando Cacciola\r
-// 24 Dec 2007 (Refactored and worked around various compiler bugs) Fernando Cacciola, Niels Dekker\r
-// 23 May 2008 (Fixed operator= const issue, added initialized_value) Niels Dekker, Fernando Cacciola\r
-// 21 Ago 2008 (Added swap) Niels Dekker, Fernando Cacciola\r
-// 20 Feb 2009 (Fixed logical const-ness issues) Niels Dekker, Fernando Cacciola\r
-//\r
-#ifndef BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP\r
-#define BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP\r
-\r
-// Note: The implementation of boost::value_initialized had to deal with the\r
-// fact that various compilers haven't fully implemented value-initialization.\r
-// The constructor of boost::value_initialized<T> works around these compiler\r
-// issues, by clearing the bytes of T, before constructing the T object it\r
-// contains. More details on these issues are at libs/utility/value_init.htm\r
-\r
-#include <boost/aligned_storage.hpp>\r
-#include <boost/detail/workaround.hpp>\r
-#include <boost/static_assert.hpp>\r
-#include <boost/type_traits/cv_traits.hpp>\r
-#include <boost/type_traits/alignment_of.hpp>\r
-#include <boost/swap.hpp>\r
-#include <cstring>\r
-#include <new>\r
-\r
-namespace boost {\r
-\r
-template<class T>\r
-class value_initialized\r
-{\r
- private :\r
- struct wrapper\r
- {\r
-#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x592))\r
- typename\r
-#endif \r
- remove_const<T>::type data;\r
- };\r
-\r
- mutable\r
-#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x592))\r
- typename\r
-#endif \r
- aligned_storage<sizeof(wrapper), alignment_of<wrapper>::value>::type x;\r
-\r
- wrapper * wrapper_address() const\r
- {\r
- return static_cast<wrapper *>( static_cast<void*>(&x));\r
- }\r
-\r
- public :\r
-\r
- value_initialized()\r
- {\r
- std::memset(&x, 0, sizeof(x));\r
-#ifdef BOOST_MSVC\r
-#pragma warning(push)\r
-#if _MSC_VER >= 1310\r
-// When using MSVC 7.1 or higher, the following placement new expression may trigger warning C4345:\r
-// "behavior change: an object of POD type constructed with an initializer of the form ()\r
-// will be default-initialized". It is safe to ignore this warning when using value_initialized.\r
-#pragma warning(disable: 4345)\r
-#endif\r
-#endif\r
- new (wrapper_address()) wrapper();\r
-#ifdef BOOST_MSVC\r
-#pragma warning(pop)\r
-#endif\r
- }\r
-\r
- value_initialized(value_initialized const & arg)\r
- {\r
- new (wrapper_address()) wrapper( static_cast<wrapper const &>(*(arg.wrapper_address())));\r
- }\r
-\r
- value_initialized & operator=(value_initialized const & arg)\r
- {\r
- // Assignment is only allowed when T is non-const.\r
- BOOST_STATIC_ASSERT( ! is_const<T>::value );\r
- *wrapper_address() = static_cast<wrapper const &>(*(arg.wrapper_address()));\r
- return *this;\r
- }\r
-\r
- ~value_initialized()\r
- {\r
- wrapper_address()->wrapper::~wrapper();\r
- }\r
-\r
- T const & data() const\r
- {\r
- return wrapper_address()->data;\r
- }\r
-\r
- T& data()\r
- {\r
- return wrapper_address()->data;\r
- }\r
-\r
- void swap(value_initialized & arg)\r
- {\r
- ::boost::swap( this->data(), arg.data() );\r
- }\r
-\r
- operator T const &() const { return this->data(); }\r
-\r
- operator T&() { return this->data(); }\r
-\r
-} ;\r
-\r
-\r
-\r
-\r
-\r
-template<class T>\r
-T const& get ( value_initialized<T> const& x )\r
-{\r
- return x.data() ;\r
-}\r
-template<class T>\r
-T& get ( value_initialized<T>& x )\r
-{\r
- return x.data() ;\r
-}\r
-\r
-template<class T>\r
-void swap ( value_initialized<T> & lhs, value_initialized<T> & rhs )\r
-{\r
- lhs.swap(rhs) ;\r
-}\r
-\r
-\r
-class initialized_value_t\r
-{\r
- public :\r
- \r
- template <class T> operator T() const\r
- {\r
- return get( value_initialized<T>() );\r
- }\r
-};\r
-\r
-initialized_value_t const initialized_value = {} ;\r
-\r
-\r
-} // namespace boost\r
-\r
-\r
-#endif\r
+// (C) Copyright 2002-2008, Fernando Luis Cacciola Carballal.
+//
+// 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)
+//
+// 21 Ago 2002 (Created) Fernando Cacciola
+// 24 Dec 2007 (Refactored and worked around various compiler bugs) Fernando Cacciola, Niels Dekker
+// 23 May 2008 (Fixed operator= const issue, added initialized_value) Niels Dekker, Fernando Cacciola
+// 21 Ago 2008 (Added swap) Niels Dekker, Fernando Cacciola
+// 20 Feb 2009 (Fixed logical const-ness issues) Niels Dekker, Fernando Cacciola
+//
+#ifndef BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP
+#define BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP
+
+// Note: The implementation of boost::value_initialized had to deal with the
+// fact that various compilers haven't fully implemented value-initialization.
+// The constructor of boost::value_initialized<T> works around these compiler
+// issues, by clearing the bytes of T, before constructing the T object it
+// contains. More details on these issues are at libs/utility/value_init.htm
+
+#include <boost/aligned_storage.hpp>
+#include <boost/detail/workaround.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/type_traits/cv_traits.hpp>
+#include <boost/type_traits/alignment_of.hpp>
+#include <boost/swap.hpp>
+#include <cstring>
+#include <new>
+
+namespace boost {
+
+template<class T>
+class value_initialized
+{
+ private :
+ struct wrapper
+ {
+#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x592))
+ typename
+#endif
+ remove_const<T>::type data;
+ };
+
+ mutable
+#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x592))
+ typename
+#endif
+ aligned_storage<sizeof(wrapper), alignment_of<wrapper>::value>::type x;
+
+ wrapper * wrapper_address() const
+ {
+ return static_cast<wrapper *>( static_cast<void*>(&x));
+ }
+
+ public :
+
+ value_initialized()
+ {
+ std::memset(&x, 0, sizeof(x));
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#if _MSC_VER >= 1310
+// When using MSVC 7.1 or higher, the following placement new expression may trigger warning C4345:
+// "behavior change: an object of POD type constructed with an initializer of the form ()
+// will be default-initialized". It is safe to ignore this warning when using value_initialized.
+#pragma warning(disable: 4345)
+#endif
+#endif
+ new (wrapper_address()) wrapper();
+#ifdef BOOST_MSVC
+#pragma warning(pop)
+#endif
+ }
+
+ value_initialized(value_initialized const & arg)
+ {
+ new (wrapper_address()) wrapper( static_cast<wrapper const &>(*(arg.wrapper_address())));
+ }
+
+ value_initialized & operator=(value_initialized const & arg)
+ {
+ // Assignment is only allowed when T is non-const.
+ BOOST_STATIC_ASSERT( ! is_const<T>::value );
+ *wrapper_address() = static_cast<wrapper const &>(*(arg.wrapper_address()));
+ return *this;
+ }
+
+ ~value_initialized()
+ {
+ wrapper_address()->wrapper::~wrapper();
+ }
+
+ T const & data() const
+ {
+ return wrapper_address()->data;
+ }
+
+ T& data()
+ {
+ return wrapper_address()->data;
+ }
+
+ void swap(value_initialized & arg)
+ {
+ ::boost::swap( this->data(), arg.data() );
+ }
+
+ operator T const &() const { return this->data(); }
+
+ operator T&() { return this->data(); }
+
+} ;
+
+
+
+
+
+template<class T>
+T const& get ( value_initialized<T> const& x )
+{
+ return x.data() ;
+}
+template<class T>
+T& get ( value_initialized<T>& x )
+{
+ return x.data() ;
+}
+
+template<class T>
+void swap ( value_initialized<T> & lhs, value_initialized<T> & rhs )
+{
+ lhs.swap(rhs) ;
+}
+
+
+class initialized_value_t
+{
+ public :
+
+ template <class T> operator T() const
+ {
+ return get( value_initialized<T>() );
+ }
+};
+
+initialized_value_t const initialized_value = {} ;
+
+
+} // namespace boost
+
+
+#endif
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