WSJT-X/boost/libs/config/test/boost_no_mem_templ_frnds.ipp

73 lines
1.4 KiB
C++

// (C) Copyright John Maddock 2001.
// Use, modification and distribution are subject to 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/config for most recent version.
// MACRO: BOOST_NO_MEMBER_TEMPLATE_FRIENDS
// TITLE: member template friends
// DESCRIPTION: Member template friend syntax
// ("template<class P> friend class frd;")
// described in the C++ Standard,
// 14.5.3, not supported.
namespace boost_no_member_template_friends{
template <class T>
class foobar;
template <class T>
class foo;
template <class T>
bool must_be_friend_proc(const foo<T>& f);
template <class T>
class foo
{
private:
template<typename Y> friend class foobar;
template<typename Y> friend class foo;
template<typename Y> friend bool must_be_friend_proc(const foo<Y>& f);
int i;
public:
foo(){ i = 0; }
template <class U>
foo(const foo<U>& f){ i = f.i; }
};
template <class T>
bool must_be_friend_proc(const foo<T>& f)
{ return f.i != 0; }
template <class T>
class foobar
{
int i;
public:
template <class U>
foobar(const foo<U>& f)
{ i = f.i; }
};
int test()
{
foo<int> fi;
foo<double> fd(fi);
must_be_friend_proc(fd);
foobar<long> fb(fi);
(void) &fb; // avoid "unused variable" warning
return 0;
}
}