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-rw-r--r--src/boost/libs/move/example/doc_template_assign.cpp98
1 files changed, 98 insertions, 0 deletions
diff --git a/src/boost/libs/move/example/doc_template_assign.cpp b/src/boost/libs/move/example/doc_template_assign.cpp
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+++ b/src/boost/libs/move/example/doc_template_assign.cpp
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+//////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2014-2014.
+// 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/move for documentation.
+//
+//////////////////////////////////////////////////////////////////////////////
+
+#include <boost/move/detail/config_begin.hpp>
+#include <boost/move/detail/meta_utils_core.hpp>
+
+#include <boost/move/move.hpp>
+
+//[template_assign_example_foo_bar
+
+class Foo
+{
+ BOOST_COPYABLE_AND_MOVABLE(Foo)
+
+ public:
+ int i;
+ explicit Foo(int val) : i(val) {}
+
+ Foo(BOOST_RV_REF(Foo) obj) : i(obj.i) {}
+
+ Foo& operator=(BOOST_RV_REF(Foo) rhs)
+ { i = rhs.i; rhs.i = 0; return *this; }
+
+ Foo& operator=(BOOST_COPY_ASSIGN_REF(Foo) rhs)
+ { i = rhs.i; return *this; } //(1)
+
+ template<class U> //(*) TEMPLATED ASSIGNMENT, potential problem
+ //<-
+ #if 1
+ typename ::boost::move_detail::disable_if_same<U, Foo, Foo&>::type
+ operator=(const U& rhs)
+ #else
+ //->
+ Foo& operator=(const U& rhs)
+ //<-
+ #endif
+ //->
+ { i = -rhs.i; return *this; } //(2)
+};
+//]
+
+struct Bar
+{
+ int i;
+ explicit Bar(int val) : i(val) {}
+};
+
+
+//<-
+#ifdef NDEBUG
+#undef NDEBUG
+#endif
+//->
+#include <cassert>
+
+int main()
+{
+//[template_assign_example_main
+ Foo foo1(1);
+ //<-
+ assert(foo1.i == 1);
+ //->
+ Foo foo2(2);
+ //<-
+ assert(foo2.i == 2);
+ Bar bar(3);
+ assert(bar.i == 3);
+ //->
+ foo2 = foo1; // Calls (1) in C++11 but (2) in C++98
+ //<-
+ assert(foo2.i == 1);
+ assert(foo1.i == 1); //Fails in C++98 unless workaround is applied
+ foo1 = bar;
+ assert(foo1.i == -3);
+ foo2 = boost::move(foo1);
+ assert(foo1.i == 0);
+ assert(foo2.i == -3);
+ //->
+ const Foo foo5(5);
+ foo2 = foo5; // Calls (1) in C++11 but (2) in C++98
+ //<-
+ assert(foo2.i == 5); //Fails in C++98 unless workaround is applied
+ assert(foo5.i == 5);
+ //->
+//]
+ return 0;
+}
+
+
+#include <boost/move/detail/config_end.hpp>