Add boost::core::split_member

include/boost/core/serialization.hpp

@@ -27,6 +27,8 @@ namespace serialization
 
 template<class T> struct version;
 
+class access;
+
 // Our own version_type replacement. This has to be in
 // the `serialization` namespace, because its only purpose
 // is to add `serialization` as an associated namespace.
@@ -54,17 +56,17 @@ using serialization::make_nvp;
 namespace detail
 {
 
-template<bool IsSaving> struct load_or_save;
+template<bool IsSaving> struct load_or_save_f;
 
-template<> struct load_or_save<true>
+template<> struct load_or_save_f<true>
 {
     template<class A, class T> void operator()( A& a, T& t, unsigned int v ) const
     {
-		save( a, t, serialization::core_version_type( v ) );
+        save( a, t, serialization::core_version_type( v ) );
     }
 };
 
-template<> struct load_or_save<false>
+template<> struct load_or_save_f<false>
 {
     template<class A, class T> void operator()( A& a, T& t, unsigned int v ) const
     {
@@ -76,7 +78,37 @@ template<> struct load_or_save<false>
 
 template<class A, class T> inline void split_free( A& a, T& t, unsigned int v )
 {
-    detail::load_or_save< A::is_saving::value >()( a, t, v );
+    detail::load_or_save_f< A::is_saving::value >()( a, t, v );
+}
+
+// split_member
+
+namespace detail
+{
+
+template<bool IsSaving, class Access = serialization::access> struct load_or_save_m;
+
+template<class Access> struct load_or_save_m<true, Access>
+{
+    template<class A, class T> void operator()( A& a, T const& t, unsigned int v ) const
+    {
+        Access::member_save( a, t, v );
+    }
+};
+
+template<class Access> struct load_or_save_m<false, Access>
+{
+    template<class A, class T> void operator()( A& a, T& t, unsigned int v ) const
+    {
+        Access::member_load( a, t, v );
+    }
+};
+
+} // namespace detail
+
+template<class A, class T> inline void split_member( A& a, T& t, unsigned int v )
+{
+    detail::load_or_save_m< A::is_saving::value >()( a, t, v );
 }
 
 } // namespace core

test/CMakeLists.txt

@@ -35,6 +35,7 @@ set(BOOST_TEST_LINK_LIBRARIES Boost::core Boost::serialization)
 
 boost_test(TYPE run SOURCES serialization_nvp_test.cpp)
 boost_test(TYPE run SOURCES serialization_split_free_test.cpp)
+boost_test(TYPE run SOURCES serialization_split_member_test.cpp)
 
 endif()
 

test/Jamfile.v2

@@ -365,6 +365,7 @@ run size_test.cpp ;
 
 run serialization_nvp_test.cpp : : : <library>/boost//serialization/<warnings>off ;
 run serialization_split_free_test.cpp : : : <library>/boost//serialization/<warnings>off ;
+run serialization_split_member_test.cpp : : : <library>/boost//serialization/<warnings>off ;
 
 use-project /boost/core/swap : ./swap ;
 build-project ./swap ;

test/serialization_split_member_test.cpp

@@ -0,0 +1,70 @@
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__clang__) && defined(__has_warning)
+# if __has_warning( "-Wdeprecated-copy" )
+#  pragma clang diagnostic ignored "-Wdeprecated-copy"
+# endif
+#endif
+
+#include <boost/core/serialization.hpp>
+
+struct X
+{
+    int a, b;
+
+private:
+
+    friend boost::serialization::access;
+
+    template<class Ar> void load( Ar& ar, unsigned /*v*/ )
+    {
+        ar >> a;
+        ar >> b;
+    }
+
+    template<class Ar> void save( Ar& ar, unsigned /*v*/ ) const
+    {
+        ar << a;
+        ar << b;
+    }
+
+    template<class Ar> void serialize( Ar& ar, unsigned v )
+    {
+        boost::core::split_member( ar, *this, v );
+    }
+};
+
+#include <boost/archive/text_oarchive.hpp>
+#include <boost/archive/text_iarchive.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <sstream>
+#include <string>
+
+int main()
+{
+    std::ostringstream os;
+
+    X x1 = { 7, 11 };
+
+    {
+        boost::archive::text_oarchive ar( os );
+        ar << x1;
+    }
+
+    std::string s = os.str();
+
+    X x2 = { 0, 0 };
+
+    {
+        std::istringstream is( s );
+        boost::archive::text_iarchive ar( is );
+        ar >> x2;
+    }
+
+    BOOST_TEST_EQ( x1.a, x2.a );
+    BOOST_TEST_EQ( x1.b, x2.b );
+
+    return boost::report_errors();
+}