79 lines
2.5 KiB
C++
79 lines
2.5 KiB
C++
// -*- C++ -*-
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// UNSUPPORTED: c++98, c++03, c++11, c++14
|
|
|
|
// <variant>
|
|
|
|
// template <size_t I, class T> struct variant_alternative; // undefined
|
|
// template <size_t I, class T> struct variant_alternative<I, const T>;
|
|
// template <size_t I, class T> struct variant_alternative<I, volatile T>;
|
|
// template <size_t I, class T> struct variant_alternative<I, const volatile T>;
|
|
// template <size_t I, class T>
|
|
// using variant_alternative_t = typename variant_alternative<I, T>::type;
|
|
//
|
|
// template <size_t I, class... Types>
|
|
// struct variant_alternative<I, variant<Types...>>;
|
|
|
|
#include <memory>
|
|
#include <type_traits>
|
|
#include <variant>
|
|
|
|
#include "test_macros.h"
|
|
#include "variant_test_helpers.hpp"
|
|
|
|
template <class V, size_t I, class E> void test() {
|
|
static_assert(
|
|
std::is_same_v<typename std::variant_alternative<I, V>::type, E>, "");
|
|
static_assert(
|
|
std::is_same_v<typename std::variant_alternative<I, const V>::type,
|
|
const E>,
|
|
"");
|
|
static_assert(
|
|
std::is_same_v<typename std::variant_alternative<I, volatile V>::type,
|
|
volatile E>,
|
|
"");
|
|
static_assert(
|
|
std::is_same_v<
|
|
typename std::variant_alternative<I, const volatile V>::type,
|
|
const volatile E>,
|
|
"");
|
|
static_assert(std::is_same_v<std::variant_alternative_t<I, V>, E>, "");
|
|
static_assert(std::is_same_v<std::variant_alternative_t<I, const V>, const E>,
|
|
"");
|
|
static_assert(
|
|
std::is_same_v<std::variant_alternative_t<I, volatile V>, volatile E>,
|
|
"");
|
|
static_assert(std::is_same_v<std::variant_alternative_t<I, const volatile V>,
|
|
const volatile E>,
|
|
"");
|
|
}
|
|
|
|
int main(int, char**) {
|
|
{
|
|
using V = std::variant<int, void *, const void *, long double>;
|
|
test<V, 0, int>();
|
|
test<V, 1, void *>();
|
|
test<V, 2, const void *>();
|
|
test<V, 3, long double>();
|
|
}
|
|
#if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
|
|
{
|
|
using V = std::variant<int, int &, const int &, int &&, long double>;
|
|
test<V, 0, int>();
|
|
test<V, 1, int &>();
|
|
test<V, 2, const int &>();
|
|
test<V, 3, int &&>();
|
|
test<V, 4, long double>();
|
|
}
|
|
#endif
|
|
|
|
return 0;
|
|
}
|