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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>
// template <class T> constexpr bool operator<(const optional<T>& x, const T& v);
// template <class T> constexpr bool operator<(const T& v, const optional<T>& x);
#include <optional>
using std::optional;
struct X
{
int i_;
constexpr X(int i) : i_(i) {}
};
constexpr bool operator < ( const X &lhs, const X &rhs )
{ return lhs.i_ < rhs.i_ ; }
int main()
{
{
typedef X T;
typedef optional<T> O;
constexpr T val(2);
constexpr O o1; // disengaged
constexpr O o2{1}; // engaged
constexpr O o3{val}; // engaged
static_assert ( (o1 < T(1)), "" );
static_assert ( !(o2 < T(1)), "" ); // equal
static_assert ( !(o3 < T(1)), "" );
static_assert ( (o2 < val), "" );
static_assert ( !(o3 < val), "" ); // equal
static_assert ( (o3 < T(3)), "" );
static_assert ( !(T(1) < o1), "" );
static_assert ( !(T(1) < o2), "" ); // equal
static_assert ( (T(1) < o3), "" );
static_assert ( !(val < o2), "" );
static_assert ( !(val < o3), "" ); // equal
static_assert ( !(T(3) < o3), "" );
}
}
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