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[boost][range] - Update to relax preconditions for the strided adaptor, and numerous fixes to inspection report issues.

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[SVN r67419]
This commit is contained in:
Neil Groves
2010-12-22 22:36:43 +00:00
parent 612cec17bb
commit d68174a51d
12 changed files with 502 additions and 113 deletions
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62
include/boost/range/adaptor/strided.hpp
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@ -30,34 +30,34 @@ namespace boost
friend class iterator_core_access;
typedef iterator_adaptor<strided_iterator<BaseIterator>, BaseIterator> super_t;
public:
typedef BOOST_DEDUCED_TYPENAME std::iterator_traits<BaseIterator>::difference_type difference_type;
strided_iterator() : m_stride() { }
strided_iterator(const strided_iterator& other)
: super_t(other), m_stride(other.m_stride) { }
explicit strided_iterator(BaseIterator base_it, difference_type stride)
: super_t(base_it), m_stride(stride) { }
strided_iterator&
operator=(const strided_iterator& other)
{
super_t::operator=(other);
// Is the interoperation of the stride safe?
m_stride = other.m_stride;
return *this;
}
void increment() { std::advance(this->base_reference(), m_stride); }
void decrement() { std::advance(this->base_reference(), -m_stride); }
void advance(difference_type n) { std::advance(this->base_reference(), n * m_stride); }
difference_type
distance_to(const strided_iterator& other) const
{
@ -66,11 +66,11 @@ namespace boost
// Using the compiler generated copy constructor and
// and assignment operator
private:
difference_type m_stride;
};
template<class BaseIterator> inline
strided_iterator<BaseIterator>
make_strided_iterator(
@ -89,9 +89,31 @@ namespace boost
public:
template< typename Difference >
strided_range(Difference stride, Rng& rng)
: super_t(make_strided_iterator(boost::begin(rng), stride),
make_strided_iterator(boost::end(rng), stride))
: super_t(make_first(rng, stride), make_last(rng, stride))
{
BOOST_ASSERT( stride >= 0 );
}
private:
template<typename Difference>
static iter_type make_first(Rng& rng, Difference stride)
{
return make_strided_iterator(boost::begin(rng), stride);
}
template<typename Difference>
static iter_type make_last(Rng& rng, Difference stride)
{
typedef BOOST_DEDUCED_TYPENAME range_iterator<Rng>::type raw_iter_t;
typedef BOOST_DEDUCED_TYPENAME range_difference<Rng>::type diff_t;
if (stride > 0)
{
raw_iter_t it = boost::end(rng);
const diff_t count = boost::size(rng);
std::advance(it, -(count % stride));
return iter_type(it, stride);
}
return make_strided_iterator(boost::end(rng), stride);
}
};
@ -99,7 +121,7 @@ namespace boost
class strided_holder : public holder<Difference>
{
public:
strided_holder(Difference value) : holder<Difference>(value) {}
explicit strided_holder(Difference value) : holder<Difference>(value) {}
};
template<class Rng, class Difference>
@ -117,32 +139,32 @@ namespace boost
}
} // namespace range_detail
using range_detail::strided_range;
namespace adaptors
{
namespace
{
const range_detail::forwarder<range_detail::strided_holder>
strided = range_detail::forwarder<range_detail::strided_holder>();
}
template<class Range, class Difference>
inline strided_range<Range>
stride(Range& rng, Difference step)
{
return strided_range<Range>(step, rng);
}
template<class Range, class Difference>
inline strided_range<const Range>
stride(const Range& rng, Difference step)
{
return strided_range<const Range>(step, rng);
}
} // namespace 'adaptors'
} // namespace 'boost'