blob: eaeeb060c4ddf8f58d7dab4442f6ab24b9ccb772 [file] [log] [blame]
// { dg-do run { target c++11 } }
// 2005-01-15 Douglas Gregor <dgregor@cs.indiana.edu>
//
// Copyright (C) 2005-2022 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// 20.7.15 polymorphic function object wrapper
#include <functional>
#include <testsuite_hooks.h>
template<typename T>
const T&
as_const(T& t)
{ return t; }
// Check that f's target is a reference_wrapper bound to obj.
template<typename Function, typename T>
bool
wraps(Function& f, T& obj)
{
using ref_wrapper_type = std::reference_wrapper<T>;
auto* p = f.template target<ref_wrapper_type>();
return std::addressof(p->get()) == std::addressof(obj);
}
struct secret {};
struct noncopyable_function_object_type
{
noncopyable_function_object_type(secret) {}
int operator()() const { return 42; }
int operator()() { return 17; }
private:
noncopyable_function_object_type();
noncopyable_function_object_type(const noncopyable_function_object_type&);
void operator=(const noncopyable_function_object_type&);
};
// Put reference_wrappers into function<> wrappers
void test06()
{
using std::function;
using std::ref;
using std::cref;
secret password;
noncopyable_function_object_type x(password);
function<int()> f(ref(x));
VERIFY( f );
VERIFY( f() == 17 );
VERIFY( f.target_type() == typeid(std::ref(x)) ); // LWG 2781
VERIFY( wraps(f, x) );
function<int()> g = f;
VERIFY( g );
VERIFY( g() == 17 );
VERIFY( g.target_type() == f.target_type() );
VERIFY( wraps(g, x) );
function<int()> h = cref(x);
VERIFY( h );
VERIFY( h() == 42 );
VERIFY( h.target_type() == typeid(std::cref(x)) );
VERIFY( wraps(h, as_const(x)) );
const function<int()>& hc = h;
VERIFY( hc.target_type() == h.target_type() );
VERIFY( wraps(hc, as_const(x)) );
}
int main()
{
test06();
return 0;
}