cxx/test/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.pass.cpp
Howard Hinnant 86ed8aefb2 LWG 1118
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@119541 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 19:22:43 +00:00

41 lines
1.4 KiB
C++

//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <tuple>
// template <class... Types> class tuple;
// template <class... Types>
// class tuple_size<tuple<Types...>>
// : public integral_constant<size_t, sizeof...(Types)> { };
#include <tuple>
#include <type_traits>
template <class T, std::size_t N>
void test()
{
static_assert((std::is_base_of<std::integral_constant<std::size_t, N>,
std::tuple_size<T> >::value), "");
static_assert((std::is_base_of<std::integral_constant<std::size_t, N>,
std::tuple_size<const T> >::value), "");
static_assert((std::is_base_of<std::integral_constant<std::size_t, N>,
std::tuple_size<volatile T> >::value), "");
static_assert((std::is_base_of<std::integral_constant<std::size_t, N>,
std::tuple_size<const volatile T> >::value), "");
}
int main()
{
test<std::tuple<>, 0>();
test<std::tuple<int>, 1>();
test<std::tuple<char, int>, 2>();
test<std::tuple<char, char*, int>, 3>();
}