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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.
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14
// <optional>
// struct nullopt_t{see below};
// constexpr nullopt_t nullopt(unspecified);
// [optional.nullopt]/2:
// Type nullopt_t shall not have a default constructor or an initializer-list constructor.
// It shall not be an aggregate and shall be a literal type.
// Constant nullopt shall be initialized with an argument of literal type.
#include <optional>
#include <type_traits>
using std::optional;
using std::nullopt_t;
using std::nullopt;
constexpr
int
test(const nullopt_t&)
{
return 3;
}
int main()
{
static_assert(( std::is_class<nullopt_t>::value), "");
static_assert(( std::is_empty<nullopt_t>::value), "");
static_assert(( std::is_literal_type<nullopt_t>::value), "");
static_assert((!std::is_default_constructible<nullopt_t>::value), "");
static_assert(test(nullopt) == 3, "");
}
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