libcxx/include/__algorithm/lexicographical_compare.h

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_H
#define _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_H

#include <__config>
#include <__algorithm/comp.h>
#include <__algorithm/comp_ref_type.h>
#include <__iterator/iterator_traits.h>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif

_LIBCPP_BEGIN_NAMESPACE_STD

template <class _Compare, class _InputIterator1, class _InputIterator2>
_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
__lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
                          _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
{
    for (; __first2 != __last2; ++__first1, (void) ++__first2)
    {
        if (__first1 == __last1 || __comp(*__first1, *__first2))
            return true;
        if (__comp(*__first2, *__first1))
            return false;
    }
    return false;
}

template <class _InputIterator1, class _InputIterator2, class _Compare>
_LIBCPP_NODISCARD_EXT inline
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
                        _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
{
    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
    return _VSTD::__lexicographical_compare<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
}

template <class _InputIterator1, class _InputIterator2>
_LIBCPP_NODISCARD_EXT inline
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
bool
lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
                        _InputIterator2 __first2, _InputIterator2 __last2)
{
    return _VSTD::lexicographical_compare(__first1, __last1, __first2, __last2,
                                         __less<typename iterator_traits<_InputIterator1>::value_type,
                                                typename iterator_traits<_InputIterator2>::value_type>());
}

_LIBCPP_END_NAMESPACE_STD

#endif // _LIBCPP___ALGORITHM_LEXICOGRAPHICAL_COMPARE_H