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// Boost.Range library
//
// Copyright Neil Groves 2009.
// Use, modification and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// For more information, see http://www.boost.org/libs/range/
//
#ifndef BOOST_RANGE_ALGORITHM_EQUAL_HPP_INCLUDED
#define BOOST_RANGE_ALGORITHM_EQUAL_HPP_INCLUDED
#include <boost/config.hpp>
#include <boost/range/concepts.hpp>
#include <iterator>
namespace boost
{
namespace range_detail
{
// An implementation of equality comparison that is optimized for iterator
// traversal categories less than RandomAccessTraversal.
template< class SinglePassTraversalReadableIterator1,
class SinglePassTraversalReadableIterator2,
class IteratorCategoryTag1,
class IteratorCategoryTag2 >
inline bool equal_impl( SinglePassTraversalReadableIterator1 first1,
SinglePassTraversalReadableIterator1 last1,
SinglePassTraversalReadableIterator2 first2,
SinglePassTraversalReadableIterator2 last2,
IteratorCategoryTag1,
IteratorCategoryTag2 )
{
do
{
// If we have reached the end of the left range then this is
// the end of the loop. They are equal if and only if we have
// simultaneously reached the end of the right range.
if (first1 == last1)
return first2 == last2;
// If we have reached the end of the right range at this line
// it indicates that the right range is shorter than the left
// and hence the result is false.
if (first2 == last2)
return false;
// continue looping if and only if the values are equal
} while(*first1++ == *first2++);
// Reaching this line in the algorithm indicates that a value
// inequality has been detected.
return false;
}
template< class SinglePassTraversalReadableIterator1,
class SinglePassTraversalReadableIterator2,
class IteratorCategoryTag1,
class IteratorCategoryTag2,
class BinaryPredicate >
inline bool equal_impl( SinglePassTraversalReadableIterator1 first1,
SinglePassTraversalReadableIterator1 last1,
SinglePassTraversalReadableIterator2 first2,
SinglePassTraversalReadableIterator2 last2,
BinaryPredicate pred,
IteratorCategoryTag1,
IteratorCategoryTag2 )
{
do
{
// If we have reached the end of the left range then this is
// the end of the loop. They are equal if and only if we have
// simultaneously reached the end of the right range.
if (first1 == last1)
return first2 == last2;
// If we have reached the end of the right range at this line
// it indicates that the right range is shorter than the left
// and hence the result is false.
if (first2 == last2)
return false;
// continue looping if and only if the values are equal
} while(pred(*first1++, *first2++));
// Reaching this line in the algorithm indicates that a value
// inequality has been detected.
return false;
}
// An implementation of equality comparison that is optimized for
// random access iterators.
template< class RandomAccessTraversalReadableIterator1,
class RandomAccessTraversalReadableIterator2 >
inline bool equal_impl( RandomAccessTraversalReadableIterator1 first1,
RandomAccessTraversalReadableIterator1 last1,
RandomAccessTraversalReadableIterator2 first2,
RandomAccessTraversalReadableIterator2 last2,
std::random_access_iterator_tag,
std::random_access_iterator_tag )
{
return ((last1 - first1) == (last2 - first2))
&& std::equal(first1, last1, first2);
}
template< class RandomAccessTraversalReadableIterator1,
class RandomAccessTraversalReadableIterator2,
class BinaryPredicate >
inline bool equal_impl( RandomAccessTraversalReadableIterator1 first1,
RandomAccessTraversalReadableIterator1 last1,
RandomAccessTraversalReadableIterator2 first2,
RandomAccessTraversalReadableIterator2 last2,
BinaryPredicate pred )
{
return ((last1 - first1) == (last2 - first2))
&& std::equal(first1, last1, first2, pred);
}
template< class SinglePassTraversalReadableIterator1,
class SinglePassTraversalReadableIterator2 >
inline bool equal( SinglePassTraversalReadableIterator1 first1,
SinglePassTraversalReadableIterator1 last1,
SinglePassTraversalReadableIterator2 first2,
SinglePassTraversalReadableIterator2 last2 )
{
BOOST_DEDUCED_TYPENAME std::iterator_traits< SinglePassTraversalReadableIterator1 >::iterator_category tag1;
BOOST_DEDUCED_TYPENAME std::iterator_traits< SinglePassTraversalReadableIterator2 >::iterator_category tag2;
return equal_impl(first1, last1, first2, last2, tag1, tag2);
}
template< class SinglePassTraversalReadableIterator1,
class SinglePassTraversalReadableIterator2,
class BinaryPredicate >
inline bool equal( SinglePassTraversalReadableIterator1 first1,
SinglePassTraversalReadableIterator1 last1,
SinglePassTraversalReadableIterator2 first2,
SinglePassTraversalReadableIterator2 last2,
BinaryPredicate pred )
{
BOOST_DEDUCED_TYPENAME std::iterator_traits< SinglePassTraversalReadableIterator1 >::iterator_category tag1;
BOOST_DEDUCED_TYPENAME std::iterator_traits< SinglePassTraversalReadableIterator2 >::iterator_category tag2;
return equal_impl(first1, last1, first2, last2, pred, tag1, tag2);
}
} // namespace range_detail
namespace range
{
/// \brief template function equal
///
/// range-based version of the equal std algorithm
///
/// \pre SinglePassRange1 is a model of the SinglePassRangeConcept
/// \pre SinglePassRange2 is a model of the SinglePassRangeConcept
/// \pre BinaryPredicate is a model of the BinaryPredicateConcept
template< class SinglePassRange1, class SinglePassRange2 >
inline bool equal( const SinglePassRange1& rng1, const SinglePassRange2& rng2 )
{
BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<SinglePassRange1> ));
BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<SinglePassRange2> ));
return ::boost::range_detail::equal(
::boost::begin(rng1), ::boost::end(rng1),
::boost::begin(rng2), ::boost::end(rng2) );
}
/// \overload
template< class SinglePassRange1, class SinglePassRange2, class BinaryPredicate >
inline bool equal( const SinglePassRange1& rng1, const SinglePassRange2& rng2,
BinaryPredicate pred )
{
BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<SinglePassRange1> ));
BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<SinglePassRange2> ));
return ::boost::range_detail::equal(
::boost::begin(rng1), ::boost::end(rng1),
::boost::begin(rng2), ::boost::end(rng2),
pred);
}
} // namespace range
using range::equal;
} // namespace boost
#endif // include guard
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