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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 T> struct hash<optional<T>>;
#include <experimental/optional>
#include <string>
#include <memory>
#include <cassert>
int main()
{
#if _LIBCPP_STD_VER > 11
using std::experimental::optional;
{
typedef int T;
optional<T> opt;
assert(std::hash<optional<T>>{}(opt) == 0);
opt = 2;
assert(std::hash<optional<T>>{}(opt) == std::hash<T>{}(*opt));
}
{
typedef std::string T;
optional<T> opt;
assert(std::hash<optional<T>>{}(opt) == 0);
opt = std::string("123");
assert(std::hash<optional<T>>{}(opt) == std::hash<T>{}(*opt));
}
{
typedef std::unique_ptr<int> T;
optional<T> opt;
assert(std::hash<optional<T>>{}(opt) == 0);
opt = std::unique_ptr<int>(new int(3));
assert(std::hash<optional<T>>{}(opt) == std::hash<T>{}(*opt));
}
#endif // _LIBCPP_STD_VER > 11
}
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