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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.
//
//===----------------------------------------------------------------------===//

// <string>

// template<class charT, class traits>
//   constexpr bool operator<(basic_string_view<charT,traits> lhs,
//                  basic_string_view<charT,traits> rhs);

#include <string_view>
#include <cassert>

#include "test_macros.h"
#include "constexpr_char_traits.hpp"

template <class S>
void
test(const S& lhs, const S& rhs, bool x, bool y)
{
    assert((lhs < rhs) == x);
    assert((rhs < lhs) == y);
}

int main()
{
    {
    typedef std::string_view S;
    test(S(""), S(""), false, false);
    test(S(""), S("abcde"), true, false);
    test(S(""), S("abcdefghij"), true, false);
    test(S(""), S("abcdefghijklmnopqrst"), true, false);
    test(S("abcde"), S(""), false, true);
    test(S("abcde"), S("abcde"), false, false);
    test(S("abcde"), S("abcdefghij"), true, false);
    test(S("abcde"), S("abcdefghijklmnopqrst"), true, false);
    test(S("abcdefghij"), S(""), false, true);
    test(S("abcdefghij"), S("abcde"), false, true);
    test(S("abcdefghij"), S("abcdefghij"), false, false);
    test(S("abcdefghij"), S("abcdefghijklmnopqrst"), true, false);
    test(S("abcdefghijklmnopqrst"), S(""), false, true);
    test(S("abcdefghijklmnopqrst"), S("abcde"), false, true);
    test(S("abcdefghijklmnopqrst"), S("abcdefghij"), false, true);
    test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), false, false);
    }

#if TEST_STD_VER > 11
    {
    typedef std::basic_string_view<char, constexpr_char_traits<char>> SV;
    constexpr SV  sv1;
    constexpr SV  sv2 { "abcde", 5 };

    static_assert (!(sv1 < sv1), "" );
    static_assert (!(sv2 < sv2), "" );

    static_assert (  sv1 < sv2,  "" );
    static_assert (!(sv2 < sv1), "" );
    }
#endif
}