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// Copyright (C) 2019-2020 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/>.
// { dg-options "-std=gnu++17" }
// { dg-do run { target c++17 } }
#include <variant>
#include <functional>
#include <testsuite_hooks.h>
// N.B. there are more std::visit tests in ./compile.cc and ./run.cc
void
test01()
{
// Verify that visitation uses INVOKE and supports arbitrary callables.
struct X
{
int sum(int i) const { return i + n; }
int product(int i) const { return i * n; }
int n;
};
std::variant<X, X*, std::reference_wrapper<X>> vobj{X{1}};
int res = std::visit(&X::n, vobj);
VERIFY( res == 1 );
std::variant<int, short> varg{2};
res = std::visit(&X::sum, vobj, varg);
VERIFY( res == 3 );
X x{4};
vobj = &x;
res = std::visit(&X::n, vobj);
VERIFY( res == 4 );
varg.emplace<short>(5);
res = std::visit(&X::sum, vobj, varg);
VERIFY( res == 9 );
x.n = 6;
res = std::visit(&X::product, vobj, varg);
VERIFY( res == 30 );
vobj = std::ref(x);
x.n = 7;
res = std::visit(&X::n, vobj);
VERIFY( res == 7 );
res = std::visit(&X::product, vobj, varg);
VERIFY( res == 35 );
}
void
test02()
{
struct NoCopy
{
NoCopy() { }
NoCopy(const NoCopy&) = delete;
NoCopy(NoCopy&&) = delete;
~NoCopy() { }
int operator()(int i) { return i; }
int operator()(const NoCopy&) { return 0; }
};
std::variant<NoCopy, int> v{1};
NoCopy f;
// Visit should not need arguments to be copyable:
int res = std::visit(f, v);
VERIFY( res == 1 );
}
int
main()
{
test01();
test02();
}
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