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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
// <optional>
// template <class U> optional<T>& operator=(U&& v);
#include <experimental/optional>
#include <type_traits>
#include <cassert>
#include <memory>
using std::experimental::optional;
struct AllowConstAssign {
AllowConstAssign() {}
AllowConstAssign(AllowConstAssign const&) {}
AllowConstAssign const& operator=(AllowConstAssign const&) const {
return *this;
}
};
struct X
{
};
int main()
{
static_assert(std::is_assignable<optional<int>, int>::value, "");
static_assert(std::is_assignable<optional<int>, int&>::value, "");
static_assert(std::is_assignable<optional<int>&, int>::value, "");
static_assert(std::is_assignable<optional<int>&, int&>::value, "");
static_assert(std::is_assignable<optional<int>&, const int&>::value, "");
static_assert(!std::is_assignable<const optional<int>&, const int&>::value, "");
static_assert(!std::is_assignable<optional<int>, X>::value, "");
{
optional<int> opt;
opt = 1;
assert(static_cast<bool>(opt) == true);
assert(*opt == 1);
}
{
optional<int> opt;
const int i = 2;
opt = i;
assert(static_cast<bool>(opt) == true);
assert(*opt == i);
}
{
optional<int> opt(3);
const int i = 2;
opt = i;
assert(static_cast<bool>(opt) == true);
assert(*opt == i);
}
{
optional<const AllowConstAssign> opt;
const AllowConstAssign other;
opt = other;
}
{
optional<std::unique_ptr<int>> opt;
opt = std::unique_ptr<int>(new int(3));
assert(static_cast<bool>(opt) == true);
assert(**opt == 3);
}
{
optional<std::unique_ptr<int>> opt(std::unique_ptr<int>(new int(2)));
opt = std::unique_ptr<int>(new int(3));
assert(static_cast<bool>(opt) == true);
assert(**opt == 3);
}
}
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