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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.
//
//===----------------------------------------------------------------------===//
// <optional>
// template <class U, class... Args>
// constexpr
// explicit optional(in_place_t, initializer_list<U> il, Args&&... args);
#include <experimental/optional>
#include <type_traits>
#include <vector>
#include <cassert>
#if _LIBCPP_STD_VER > 11
using std::experimental::optional;
using std::experimental::in_place_t;
using std::experimental::in_place;
class X
{
int i_;
int j_ = 0;
public:
X() : i_(0) {}
X(int i) : i_(i) {}
X(int i, int j) : i_(i), j_(j) {}
~X() {}
friend bool operator==(const X& x, const X& y)
{return x.i_ == y.i_ && x.j_ == y.j_;}
};
class Y
{
int i_;
int j_ = 0;
public:
constexpr Y() : i_(0) {}
constexpr Y(int i) : i_(i) {}
constexpr Y(std::initializer_list<int> il) : i_(il.begin()[0]), j_(il.begin()[1]) {}
friend constexpr bool operator==(const Y& x, const Y& y)
{return x.i_ == y.i_ && x.j_ == y.j_;}
};
class Z
{
int i_;
int j_ = 0;
public:
constexpr Z() : i_(0) {}
constexpr Z(int i) : i_(i) {}
constexpr Z(std::initializer_list<int> il) : i_(il.begin()[0]), j_(il.begin()[1])
{throw 6;}
friend constexpr bool operator==(const Z& x, const Z& y)
{return x.i_ == y.i_ && x.j_ == y.j_;}
};
#endif // _LIBCPP_STD_VER > 11
int main()
{
#if _LIBCPP_STD_VER > 11
{
static_assert(!std::is_constructible<X, std::initializer_list<int>&>::value, "");
static_assert(!std::is_constructible<optional<X>, std::initializer_list<int>&>::value, "");
}
{
optional<std::vector<int>> opt(in_place, {3, 1});
assert(static_cast<bool>(opt) == true);
assert((*opt == std::vector<int>{3, 1}));
assert(opt->size() == 2);
}
{
optional<std::vector<int>> opt(in_place, {3, 1}, std::allocator<int>());
assert(static_cast<bool>(opt) == true);
assert((*opt == std::vector<int>{3, 1}));
assert(opt->size() == 2);
}
{
static_assert(std::is_constructible<optional<Y>, std::initializer_list<int>&>::value, "");
constexpr optional<Y> opt(in_place, {3, 1});
static_assert(static_cast<bool>(opt) == true, "");
static_assert(*opt == Y{3, 1}, "");
struct test_constexpr_ctor
: public optional<Y>
{
constexpr test_constexpr_ctor(in_place_t, std::initializer_list<int> i)
: optional<Y>(in_place, i) {}
};
}
{
static_assert(std::is_constructible<optional<Z>, std::initializer_list<int>&>::value, "");
try
{
optional<Z> opt(in_place, {3, 1});
assert(false);
}
catch (int i)
{
assert(i == 6);
}
struct test_constexpr_ctor
: public optional<Z>
{
constexpr test_constexpr_ctor(in_place_t, std::initializer_list<int> i)
: optional<Z>(in_place, i) {}
};
}
#endif // _LIBCPP_STD_VER > 11
}
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