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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/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;
}
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