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Boost.RangeEx merged into Boost.Range

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[SVN r60897]
This commit is contained in:
Neil Groves
2010-03-28 16:08:35 +00:00
parent 1461479a17
commit b0d1db7c2e
471 changed files with 48610 additions and 2065 deletions
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265
include/boost/range/concepts.hpp Executable file → Normal file
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@ -1,5 +1,10 @@
// Boost.Range library concept checks
//
// Copyright Neil Groves 2009. Use, modification and distribution
// are 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)
//
// Copyright Daniel Walker 2006. Use, modification and distribution
// are subject to the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
@ -15,6 +20,9 @@
#include <boost/iterator/iterator_concepts.hpp>
#include <boost/range/begin.hpp>
#include <boost/range/end.hpp>
#include <boost/range/iterator.hpp>
#include <boost/range/value_type.hpp>
#include <boost/range/detail/misc_concept.hpp>
/*!
* \file
@ -29,20 +37,15 @@
* concept.
*
* \code
* function_requires<ForwardRangeConcept<T> >();
* BOOST_CONCEPT_ASSERT((ForwardRangeConcept<T>));
* \endcode
*
* An additional concept check is required for the value access
* property of the range. For example to check for a
* ForwardReadableRange, the following code is required.
* A different concept check is required to ensure writeable value
* access. For example to check for a ForwardRange that can be written
* to, the following code is required.
*
* \code
* function_requires<ForwardRangeConcept<T> >();
* function_requires<
* ReadableIteratorConcept<
* typename range_iterator<T>::type
* >
* >();
* BOOST_CONCEPT_ASSERT((WriteableForwardRangeConcept<T>));
* \endcode
*
* \see http://www.boost.org/libs/range/doc/range.html for details
@ -55,84 +58,218 @@
namespace boost {
namespace range_detail {
// Rationale for the inclusion of redefined iterator concept
// classes:
//
// The Range algorithms often do not require that the iterators are
// Assignable, but the correct standard conformant iterators
// do require the iterators to be a model of the Assignable concept.
// Iterators that contains a functor that is not assignable therefore
// are not correct models of the standard iterator concepts,
// despite being adequate for most algorithms. An example of this
// use case is the combination of the boost::adaptors::filtered
// class with a boost::lambda::bind generated functor.
// Ultimately modeling the range concepts using composition
// with the Boost.Iterator concepts would render the library
// incompatible with many common Boost.Lambda expressions.
template<typename Iterator>
struct IncrementableIteratorConcept : CopyConstructible<Iterator>
{
typedef typename iterator_traversal<Iterator>::type traversal_category;
BOOST_CONCEPT_ASSERT((
Convertible<
traversal_category,
incrementable_traversal_tag
>));
BOOST_CONCEPT_USAGE(IncrementableIteratorConcept)
{
++i;
(void)i++;
}
private:
Iterator i;
};
template<typename Iterator>
struct SinglePassIteratorConcept
: IncrementableIteratorConcept<Iterator>
, EqualityComparable<Iterator>
{
BOOST_CONCEPT_ASSERT((
Convertible<
typename SinglePassIteratorConcept::traversal_category,
single_pass_traversal_tag
>));
};
template<typename Iterator>
struct ForwardIteratorConcept
: SinglePassIteratorConcept<Iterator>
, DefaultConstructible<Iterator>
{
typedef typename boost::detail::iterator_traits<Iterator>::difference_type difference_type;
BOOST_MPL_ASSERT((is_integral<difference_type>));
BOOST_MPL_ASSERT_RELATION(std::numeric_limits<difference_type>::is_signed, ==, true);
BOOST_CONCEPT_ASSERT((
Convertible<
typename ForwardIteratorConcept::traversal_category,
forward_traversal_tag
>));
};
template<typename Iterator>
struct BidirectionalIteratorConcept
: ForwardIteratorConcept<Iterator>
{
BOOST_CONCEPT_ASSERT((
Convertible<
typename BidirectionalIteratorConcept::traversal_category,
bidirectional_traversal_tag
>));
BOOST_CONCEPT_USAGE(BidirectionalIteratorConcept)
{
--i;
(void)i--;
}
private:
Iterator i;
};
template<typename Iterator>
struct RandomAccessIteratorConcept
: BidirectionalIteratorConcept<Iterator>
{
BOOST_CONCEPT_ASSERT((
Convertible<
typename RandomAccessIteratorConcept::traversal_category,
random_access_traversal_tag
>));
BOOST_CONCEPT_USAGE(RandomAccessIteratorConcept)
{
i += n;
i = i + n;
i = n + i;
i -= n;
i = i - n;
n = i - j;
}
private:
typename RandomAccessIteratorConcept::difference_type n;
Iterator i;
Iterator j;
};
} // namespace range_detail
//! Check if a type T models the SinglePassRange range concept.
template<typename T>
struct SinglePassRangeConcept
struct SinglePassRangeConcept
{
typedef typename range_iterator<T const>::type range_const_iterator;
typedef typename range_iterator<T>::type range_iterator;
typedef typename range_iterator<T const>::type const_iterator;
typedef typename range_iterator<T>::type iterator;
void constraints()
{
function_requires<
boost_concepts::SinglePassIteratorConcept<
range_iterator
>
>();
i = boost::begin(a);
i = boost::end(a);
const_constraints(a);
BOOST_CONCEPT_ASSERT((range_detail::SinglePassIteratorConcept<iterator>));
BOOST_CONCEPT_ASSERT((range_detail::SinglePassIteratorConcept<const_iterator>));
BOOST_CONCEPT_USAGE(SinglePassRangeConcept)
{
// This has been modified from assigning to this->i
// (where i was a member variable) to improve
// compatibility with Boost.Lambda
iterator i1 = boost::begin(*m_range);
iterator i2 = boost::end(*m_range);
ignore_unused_variable_warning(i1);
ignore_unused_variable_warning(i2);
const_constraints(*m_range);
}
void const_constraints(const T& a)
private:
void const_constraints(const T& const_range)
{
ci = boost::begin(a);
ci = boost::end(a);
const_iterator ci1 = boost::begin(const_range);
const_iterator ci2 = boost::end(const_range);
ignore_unused_variable_warning(ci1);
ignore_unused_variable_warning(ci2);
}
T a;
range_iterator i;
range_const_iterator ci;
// Rationale:
// The type of m_range is T* rather than T because it allows
// T to be an abstract class. The other obvious alternative of
// T& produces a warning on some compilers.
T* m_range;
};
//! Check if a type T models the ForwardRange range concept.
template<typename T>
struct ForwardRangeConcept
struct ForwardRangeConcept : SinglePassRangeConcept<T>
{
void constraints()
BOOST_CONCEPT_ASSERT((range_detail::ForwardIteratorConcept<typename ForwardRangeConcept::iterator>));
BOOST_CONCEPT_ASSERT((range_detail::ForwardIteratorConcept<typename ForwardRangeConcept::const_iterator>));
};
template<typename Range>
struct WriteableRangeConcept
{
typedef typename range_iterator<Range>::type iterator;
BOOST_CONCEPT_USAGE(WriteableRangeConcept)
{
function_requires<
SinglePassRangeConcept<T>
>();
function_requires<
boost_concepts::ForwardTraversalConcept<
typename range_iterator<T>::type
>
>();
*i = v;
}
private:
iterator i;
typename range_value<Range>::type v;
};
//! Check if a type T models the WriteableForwardRange range concept.
template<typename T>
struct WriteableForwardRangeConcept
: ForwardRangeConcept<T>
, WriteableRangeConcept<T>
{
};
//! Check if a type T models the BidirectionalRange range concept.
template<typename T>
struct BidirectionalRangeConcept
struct BidirectionalRangeConcept : ForwardRangeConcept<T>
{
BOOST_CONCEPT_ASSERT((BidirectionalIteratorConcept<typename BidirectionalRangeConcept::iterator>));
BOOST_CONCEPT_ASSERT((BidirectionalIteratorConcept<typename BidirectionalRangeConcept::const_iterator>));
};
//! Check if a type T models the WriteableBidirectionalRange range concept.
template<typename T>
struct WriteableBidirectionalRangeConcept
: BidirectionalRangeConcept<T>
, WriteableRangeConcept<T>
{
void constraints()
{
function_requires<
ForwardRangeConcept<T>
>();
function_requires<
boost_concepts::BidirectionalTraversalConcept<
typename range_iterator<T>::type
>
>();
}
};
//! Check if a type T models the RandomAccessRange range concept.
template<typename T>
struct RandomAccessRangeConcept
struct RandomAccessRangeConcept : BidirectionalRangeConcept<T>
{
BOOST_CONCEPT_ASSERT((RandomAccessIteratorConcept<typename RandomAccessRangeConcept::iterator>));
BOOST_CONCEPT_ASSERT((RandomAccessIteratorConcept<typename RandomAccessRangeConcept::const_iterator>));
};
//! Check if a type T models the WriteableRandomAccessRange range concept.
template<typename T>
struct WriteableRandomAccessRangeConcept
: RandomAccessRangeConcept<T>
, WriteableRangeConcept<T>
{
void constraints()
{
function_requires<
BidirectionalRangeConcept<T>
>();
function_requires<
boost_concepts::RandomAccessTraversalConcept<
typename range_iterator<T>::type
>
>();
}
};
} // namespace boost