Merge 8db591c into 6b4e6fe

include/boost/any.hpp

@@ -3,18 +3,20 @@
 #ifndef BOOST_ANY_INCLUDED
 #define BOOST_ANY_INCLUDED
 
-#if defined(_MSC_VER)
+#include <boost/config.hpp>
+#ifdef BOOST_HAS_PRAGMA_ONCE
 # pragma once
 #endif
 
 // what:  variant type boost::any
 // who:   contributed by Kevlin Henney,
 //        with features contributed and bugs found by
-//        Antony Polukhin, Ed Brey, Mark Rodgers, 
+//        Antony Polukhin, Ed Brey, Mark Rodgers,
 //        Peter Dimov, and James Curran
 // when:  July 2001, April 2013 - 2020
 
-#include <boost/config.hpp>
+#include <boost/anys/bad_any_cast.hpp>
+#include <boost/anys/fwd.hpp>
 #include <boost/type_index.hpp>
 #include <boost/type_traits/remove_reference.hpp>
 #include <boost/type_traits/decay.hpp>
@@ -47,6 +49,10 @@ namespace boost
                 BOOST_DEDUCED_TYPENAME remove_cv<BOOST_DEDUCED_TYPENAME decay<const ValueType>::type>::type
             >(value))
         {
+            BOOST_STATIC_ASSERT_MSG(
+                !anys::detail::is_basic_any<ValueType>::value,
+                "boost::any shall not be constructed from boost::anys::basic_any"
+            );
         }
 
         any(const any & other)
@@ -69,6 +75,10 @@ namespace boost
             , typename boost::disable_if<boost::is_const<ValueType> >::type* = 0) // disable if value has type `const ValueType&&`
           : content(new holder< typename decay<ValueType>::type >(static_cast<ValueType&&>(value)))
         {
+            BOOST_STATIC_ASSERT_MSG(
+                !anys::detail::is_basic_any<typename boost::decay<ValueType>::type>::value,
+                "boost::any shall not be constructed from boost::anys::basic_any"
+            );
         }
 #endif
 
@@ -92,6 +102,10 @@ namespace boost
         template<typename ValueType>
         any & operator=(const ValueType & rhs)
         {
+            BOOST_STATIC_ASSERT_MSG(
+                !anys::detail::is_basic_any<ValueType>::value,
+                "boost::anys::basic_any shall not be assigned into boost::any"
+            );
             any(rhs).swap(*this);
             return *this;
         }
@@ -102,7 +116,7 @@ namespace boost
             return *this;
         }
 
-#else 
+#else
         any & operator=(const any& rhs)
         {
             any(rhs).swap(*this);
@@ -121,6 +135,10 @@ namespace boost
         template <class ValueType>
         any & operator=(ValueType&& rhs)
         {
+            BOOST_STATIC_ASSERT_MSG(
+                !anys::detail::is_basic_any<typename boost::decay<ValueType>::type>::value,
+                "boost::anys::basic_any shall not be assigned into boost::any"
+            );
             any(static_cast<ValueType&&>(rhs)).swap(*this);
             return *this;
         }
@@ -224,27 +242,12 @@ namespace boost
         placeholder * content;
 
     };
- 
+
     inline void swap(any & lhs, any & rhs) BOOST_NOEXCEPT
     {
         lhs.swap(rhs);
     }
 
-    class BOOST_SYMBOL_VISIBLE bad_any_cast :
-#ifndef BOOST_NO_RTTI
-        public std::bad_cast
-#else
-        public std::exception
-#endif
-    {
-    public:
-        const char * what() const BOOST_NOEXCEPT_OR_NOTHROW BOOST_OVERRIDE
-        {
-            return "boost::bad_any_cast: "
-                   "failed conversion using boost::any_cast";
-        }
-    };
-
     template<typename ValueType>
     ValueType * any_cast(any * operand) BOOST_NOEXCEPT
     {
@@ -271,9 +274,9 @@ namespace boost
         if(!result)
             boost::throw_exception(bad_any_cast());
 
-        // Attempt to avoid construction of a temporary object in cases when 
+        // Attempt to avoid construction of a temporary object in cases when
         // `ValueType` is not a reference. Example:
-        // `static_cast<std::string>(*result);` 
+        // `static_cast<std::string>(*result);`
         // which is equal to `std::string(*result);`
         typedef BOOST_DEDUCED_TYPENAME boost::conditional<
             boost::is_reference<ValueType>::value,
@@ -305,7 +308,7 @@ namespace boost
         BOOST_STATIC_ASSERT_MSG(
             boost::is_rvalue_reference<ValueType&&>::value /*true if ValueType is rvalue or just a value*/
             || boost::is_const< typename boost::remove_reference<ValueType>::type >::value,
-            "boost::any_cast shall not be used for getting nonconst references to temporary objects" 
+            "boost::any_cast shall not be used for getting nonconst references to temporary objects"
         );
         return any_cast<ValueType>(operand);
     }

include/boost/anys/bad_any_cast.hpp

@@ -0,0 +1,40 @@
+// Copyright Antony Polukhin, 2020-2021.
+//
+// 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)
+
+// See http://www.boost.org/libs/any for Documentation.
+
+#ifndef BOOST_ANYS_UNIQUE_ANY_INCLUDED
+#define BOOST_ANYS_UNIQUE_ANY_INCLUDED
+
+#include <boost/config.hpp>
+#ifdef BOOST_HAS_PRAGMA_ONCE
+#   pragma once
+#endif
+
+#include <boost/type_index.hpp>
+
+
+namespace boost {
+
+class BOOST_SYMBOL_VISIBLE bad_any_cast :
+#ifndef BOOST_NO_RTTI
+    public std::bad_cast
+#else
+    public std::exception
+#endif
+{
+public:
+    const char * what() const BOOST_NOEXCEPT_OR_NOTHROW BOOST_OVERRIDE
+    {
+        return "boost::bad_any_cast: "
+               "failed conversion using boost::any_cast";
+    }
+};
+
+} // namespace boost
+
+
+#endif // BOOST_ANYS_UNIQUE_ANY_INCLUDED