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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.
//
//===----------------------------------------------------------------------===//
#ifndef SUPPORT_TEST_CONVERTIBLE_HPP
#define SUPPORT_TEST_CONVERTIBLE_HPP
// "test_convertible<Tp, Args...>()" is a metafunction used to check if 'Tp'
// is implicitly convertible from 'Args...' for any number of arguments,
// Unlike 'std::is_convertible' which only allows checking for single argument
// conversions.
#include <type_traits>
#include "test_macros.h"
#if TEST_STD_VER < 11
#error test_convertible.hpp requires C++11 or newer
#endif
namespace detail {
template <class Tp> void eat_type(Tp);
template <class Tp, class ...Args>
constexpr auto test_convertible_imp(int)
-> decltype(eat_type<Tp>({std::declval<Args>()...}), true)
{ return true; }
template <class Tp, class ...Args>
constexpr auto test_convertible_imp(long) -> bool { return false; }
}
template <class Tp, class ...Args>
constexpr bool test_convertible()
{ return detail::test_convertible_imp<Tp, Args...>(0); }
#endif // SUPPORT_TEST_CONVERTIBLE_HPP
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