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//===----------------------------------------------------------------------===//
//
// 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... UTypes>
// explicit tuple(UTypes&&... u);
// UNSUPPORTED: c++98, c++03
// MODULES_DEFINES: _LIBCPP_ENABLE_TUPLE_IMPLICIT_REDUCED_ARITY_EXTENSION
#define _LIBCPP_ENABLE_TUPLE_IMPLICIT_REDUCED_ARITY_EXTENSION
#include <tuple>
#include <cassert>
#include <type_traits>
#include <string>
#include <system_error>
#include "test_macros.h"
#include "test_convertible.hpp"
#include "MoveOnly.h"
struct NoDefault { NoDefault() = delete; };
// Make sure the _Up... constructor SFINAEs out when the types that
// are not explicitly initialized are not all default constructible.
// Otherwise, std::is_constructible would return true but instantiating
// the constructor would fail.
void test_default_constructible_extension_sfinae()
{
typedef MoveOnly MO;
typedef NoDefault ND;
{
typedef std::tuple<MO, ND> Tuple;
static_assert(!std::is_constructible<Tuple, MO>::value, "");
static_assert(std::is_constructible<Tuple, MO, ND>::value, "");
static_assert(test_convertible<Tuple, MO, ND>(), "");
}
{
typedef std::tuple<MO, MO, ND> Tuple;
static_assert(!std::is_constructible<Tuple, MO, MO>::value, "");
static_assert(std::is_constructible<Tuple, MO, MO, ND>::value, "");
static_assert(test_convertible<Tuple, MO, MO, ND>(), "");
}
{
// Same idea as above but with a nested tuple type.
typedef std::tuple<MO, ND> Tuple;
typedef std::tuple<MO, Tuple, MO, MO> NestedTuple;
static_assert(!std::is_constructible<
NestedTuple, MO, MO, MO, MO>::value, "");
static_assert(std::is_constructible<
NestedTuple, MO, Tuple, MO, MO>::value, "");
}
{
typedef std::tuple<MO, int> Tuple;
typedef std::tuple<MO, Tuple, MO, MO> NestedTuple;
static_assert(std::is_constructible<
NestedTuple, MO, MO, MO, MO>::value, "");
static_assert(test_convertible<
NestedTuple, MO, MO, MO, MO>(), "");
static_assert(std::is_constructible<
NestedTuple, MO, Tuple, MO, MO>::value, "");
static_assert(test_convertible<
NestedTuple, MO, Tuple, MO, MO>(), "");
}
}
std::tuple<std::string, int, std::error_code> doc_example() {
return {"hello world", 42};
}
// Test that the example given in UsingLibcxx.rst actually works.
void test_example_from_docs() {
auto tup = doc_example();
assert(std::get<0>(tup) == "hello world");
assert(std::get<1>(tup) == 42);
assert(std::get<2>(tup) == std::error_code{});
}
int main()
{
{
using E = MoveOnly;
using Tup = std::tuple<E, E, E>;
static_assert(test_convertible<Tup, E, E, E>(), "");
Tup t = {E(0), E(1)};
static_assert(test_convertible<Tup, E, E>(), "");
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == 1);
assert(std::get<2>(t) == MoveOnly());
Tup t2 = {E(0)};
static_assert(test_convertible<Tup, E>(), "");
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == E());
assert(std::get<2>(t) == E());
}
// Check that SFINAE is properly applied with the default reduced arity
// constructor extensions.
test_default_constructible_extension_sfinae();
test_example_from_docs();
}
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