ext-boost/boost/range/iterator_range_core.hpp
2015-08-16 20:45:50 -03:00

884 lines
28 KiB
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// Boost.Range library
//
// Copyright Neil Groves & Thorsten Ottosen & Pavol Droba 2003-2004.
// 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/
//
// Credits:
// 'michel' reported Trac 9072 which included a patch for allowing references
// to function types.
//
#ifndef BOOST_RANGE_ITERATOR_RANGE_CORE_HPP_INCLUDED
#define BOOST_RANGE_ITERATOR_RANGE_CORE_HPP_INCLUDED
#include <boost/config.hpp> // Define __STL_CONFIG_H, if appropriate.
#include <boost/detail/workaround.hpp>
#if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1500))
#pragma warning( push )
#pragma warning( disable : 4996 )
#endif
#include <boost/assert.hpp>
#include <boost/iterator/iterator_traits.hpp>
#include <boost/iterator/iterator_facade.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/not.hpp>
#include <boost/mpl/or.hpp>
#include <boost/type_traits/is_abstract.hpp>
#include <boost/type_traits/is_array.hpp>
#include <boost/type_traits/is_base_and_derived.hpp>
#include <boost/type_traits/is_convertible.hpp>
#include <boost/type_traits/is_function.hpp>
#include <boost/type_traits/is_pointer.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/range/functions.hpp>
#include <boost/range/iterator.hpp>
#include <boost/range/difference_type.hpp>
#include <boost/range/has_range_iterator.hpp>
#include <boost/range/algorithm/equal.hpp>
#include <boost/range/detail/safe_bool.hpp>
#include <boost/utility/enable_if.hpp>
#include <iterator>
#include <algorithm>
#include <cstddef>
/*! \file
Defines the \c iterator_class and related functions.
\c iterator_range is a simple wrapper of iterator pair idiom. It provides
a rich subset of Container interface.
*/
namespace boost
{
namespace iterator_range_detail
{
//
// The functions adl_begin and adl_end are implemented in a separate
// class for gcc-2.9x
//
template<class IteratorT>
struct iterator_range_impl {
template< class ForwardRange >
static IteratorT adl_begin( ForwardRange& r )
{
return IteratorT( boost::begin( r ) );
}
template< class ForwardRange >
static IteratorT adl_end( ForwardRange& r )
{
return IteratorT( boost::end( r ) );
}
};
template< class Left, class Right >
inline bool less_than( const Left& l, const Right& r )
{
return std::lexicographical_compare( boost::begin(l),
boost::end(l),
boost::begin(r),
boost::end(r) );
}
template< class Left, class Right >
inline bool greater_than( const Left& l, const Right& r )
{
return iterator_range_detail::less_than(r,l);
}
template< class Left, class Right >
inline bool less_or_equal_than( const Left& l, const Right& r )
{
return !iterator_range_detail::less_than(r,l);
}
template< class Left, class Right >
inline bool greater_or_equal_than( const Left& l, const Right& r )
{
return !iterator_range_detail::less_than(l,r);
}
// This version is maintained since it is used in other boost libraries
// such as Boost.Assign
template< class Left, class Right >
inline bool equal(const Left& l, const Right& r)
{
return boost::equal(l, r);
}
struct range_tag
{
};
struct const_range_tag
{
};
struct iterator_range_tag
{
};
typedef char (&incrementable_t)[1];
typedef char (&bidirectional_t)[2];
typedef char (&random_access_t)[3];
incrementable_t test_traversal_tag(boost::incrementable_traversal_tag);
bidirectional_t test_traversal_tag(boost::bidirectional_traversal_tag);
random_access_t test_traversal_tag(boost::random_access_traversal_tag);
template<std::size_t S>
struct pure_iterator_traversal_impl
{
typedef boost::incrementable_traversal_tag type;
};
template<>
struct pure_iterator_traversal_impl<sizeof(bidirectional_t)>
{
typedef boost::bidirectional_traversal_tag type;
};
template<>
struct pure_iterator_traversal_impl<sizeof(random_access_t)>
{
typedef boost::random_access_traversal_tag type;
};
template<typename IteratorT>
struct pure_iterator_traversal
{
typedef
BOOST_DEDUCED_TYPENAME iterator_traversal<IteratorT>::type
traversal_t;
BOOST_STATIC_CONSTANT(
std::size_t,
traversal_i = sizeof(iterator_range_detail::test_traversal_tag((traversal_t())))
);
typedef
BOOST_DEDUCED_TYPENAME pure_iterator_traversal_impl<traversal_i>::type
type;
};
template<class IteratorT, class TraversalTag>
class iterator_range_base
: public iterator_range_tag
{
typedef range_detail::safe_bool<
IteratorT iterator_range_base<IteratorT, TraversalTag>::*
> safe_bool_t;
typedef iterator_range_base<IteratorT, TraversalTag> type;
protected:
typedef iterator_range_impl<IteratorT> impl;
public:
typedef BOOST_DEDUCED_TYPENAME
safe_bool_t::unspecified_bool_type unspecified_bool_type;
typedef BOOST_DEDUCED_TYPENAME
iterator_value<IteratorT>::type value_type;
typedef BOOST_DEDUCED_TYPENAME
iterator_difference<IteratorT>::type difference_type;
typedef std::size_t size_type; // note: must be unsigned
// Needed because value-type is the same for
// const and non-const iterators
typedef BOOST_DEDUCED_TYPENAME
iterator_reference<IteratorT>::type reference;
//! const_iterator type
/*!
There is no distinction between const_iterator and iterator.
These typedefs are provides to fulfill container interface
*/
typedef IteratorT const_iterator;
//! iterator type
typedef IteratorT iterator;
protected:
iterator_range_base()
: m_Begin()
, m_End()
{
}
template<class Iterator>
iterator_range_base(Iterator Begin, Iterator End)
: m_Begin(Begin)
, m_End(End)
{
}
public:
IteratorT begin() const
{
return m_Begin;
}
IteratorT end() const
{
return m_End;
}
bool empty() const
{
return m_Begin == m_End;
}
operator unspecified_bool_type() const
{
return safe_bool_t::to_unspecified_bool(
m_Begin != m_End, &iterator_range_base::m_Begin);
}
bool operator!() const
{
return empty();
}
bool equal(const iterator_range_base& r) const
{
return m_Begin == r.m_Begin && m_End == r.m_End;
}
reference front() const
{
BOOST_ASSERT(!empty());
return *m_Begin;
}
void drop_front()
{
BOOST_ASSERT(!empty());
++m_Begin;
}
void drop_front(difference_type n)
{
BOOST_ASSERT(n >= difference_type());
std::advance(this->m_Begin, n);
}
// Deprecated
void pop_front() { drop_front(); }
protected:
template<class Iterator>
void assign(Iterator first, Iterator last)
{
m_Begin = first;
m_End = last;
}
template<class SinglePassRange>
void assign(const SinglePassRange& r)
{
m_Begin = impl::adl_begin(r);
m_End = impl::adl_end(r);
}
template<class SinglePassRange>
void assign(SinglePassRange& r)
{
m_Begin = impl::adl_begin(r);
m_End = impl::adl_end(r);
}
IteratorT m_Begin;
IteratorT m_End;
};
template<class IteratorT>
class iterator_range_base<IteratorT, bidirectional_traversal_tag>
: public iterator_range_base<IteratorT, incrementable_traversal_tag>
{
typedef iterator_range_base<IteratorT, incrementable_traversal_tag> base_type;
protected:
iterator_range_base()
{
}
template<class Iterator>
iterator_range_base(Iterator first, Iterator last)
: base_type(first, last)
{
}
public:
typedef BOOST_DEDUCED_TYPENAME base_type::difference_type difference_type;
typedef BOOST_DEDUCED_TYPENAME base_type::reference reference;
reference back() const
{
BOOST_ASSERT(!this->empty());
return *boost::prior(this->m_End);
}
void drop_back()
{
BOOST_ASSERT(!this->empty());
--this->m_End;
}
void drop_back(difference_type n)
{
BOOST_ASSERT(n >= difference_type());
std::advance(this->m_End, -n);
}
// Deprecated
void pop_back() { drop_back(); }
};
template<class IteratorT>
class iterator_range_base<IteratorT, random_access_traversal_tag>
: public iterator_range_base<IteratorT, bidirectional_traversal_tag>
{
typedef iterator_range_base<
IteratorT, bidirectional_traversal_tag> base_type;
public:
typedef BOOST_DEDUCED_TYPENAME
boost::mpl::if_<
boost::mpl::or_<
boost::is_abstract<
BOOST_DEDUCED_TYPENAME base_type::value_type
>,
boost::is_array<
BOOST_DEDUCED_TYPENAME base_type::value_type
>,
boost::is_function<
BOOST_DEDUCED_TYPENAME base_type::value_type
>
>,
BOOST_DEDUCED_TYPENAME base_type::reference,
BOOST_DEDUCED_TYPENAME base_type::value_type
>::type abstract_value_type;
// Rationale:
// typedef these here to reduce verbiage in the implementation of this
// type.
typedef BOOST_DEDUCED_TYPENAME base_type::difference_type difference_type;
typedef BOOST_DEDUCED_TYPENAME base_type::size_type size_type;
typedef BOOST_DEDUCED_TYPENAME base_type::reference reference;
protected:
iterator_range_base()
{
}
template<class Iterator>
iterator_range_base(Iterator first, Iterator last)
: base_type(first, last)
{
}
public:
reference operator[](difference_type at) const
{
BOOST_ASSERT(at >= 0);
BOOST_ASSERT(static_cast<typename base_type::size_type>(at) < size());
return this->m_Begin[at];
}
//
// When storing transform iterators, operator[]()
// fails because it returns by reference. Therefore
// operator()() is provided for these cases.
//
abstract_value_type operator()(difference_type at) const
{
BOOST_ASSERT(at >= 0);
BOOST_ASSERT(static_cast<typename base_type::size_type>(at) < size());
return this->m_Begin[at];
}
BOOST_DEDUCED_TYPENAME base_type::size_type size() const
{
return this->m_End - this->m_Begin;
}
};
}
// iterator range template class -----------------------------------------//
//! iterator_range class
/*!
An \c iterator_range delimits a range in a sequence by beginning and ending iterators.
An iterator_range can be passed to an algorithm which requires a sequence as an input.
For example, the \c toupper() function may be used most frequently on strings,
but can also be used on iterator_ranges:
\code
boost::tolower( find( s, "UPPERCASE STRING" ) );
\endcode
Many algorithms working with sequences take a pair of iterators,
delimiting a working range, as an arguments. The \c iterator_range class is an
encapsulation of a range identified by a pair of iterators.
It provides a collection interface,
so it is possible to pass an instance to an algorithm requiring a collection as an input.
*/
template<class IteratorT>
class iterator_range
: public iterator_range_detail::iterator_range_base<
IteratorT,
BOOST_DEDUCED_TYPENAME iterator_range_detail::pure_iterator_traversal<IteratorT>::type
>
{
typedef iterator_range_detail::iterator_range_base<
IteratorT,
BOOST_DEDUCED_TYPENAME iterator_range_detail::pure_iterator_traversal<IteratorT>::type
> base_type;
template<class Source>
struct is_compatible_range_
: is_convertible<
BOOST_DEDUCED_TYPENAME mpl::eval_if<
has_range_iterator<Source>,
range_iterator<Source>,
mpl::identity<void>
>::type,
BOOST_DEDUCED_TYPENAME base_type::iterator
>
{
};
template<class Source>
struct is_compatible_range
: mpl::and_<
mpl::not_<
is_convertible<
Source,
BOOST_DEDUCED_TYPENAME base_type::iterator
>
>,
is_compatible_range_<Source>
>
{
};
protected:
typedef iterator_range_detail::iterator_range_impl<IteratorT> impl;
public:
typedef iterator_range<IteratorT> type;
iterator_range()
{
}
template<class Iterator>
iterator_range(Iterator first, Iterator last)
: base_type(first, last)
{
}
template<class SinglePassRange>
iterator_range(
const SinglePassRange& r,
BOOST_DEDUCED_TYPENAME ::boost::enable_if<
is_compatible_range<const SinglePassRange>
>::type* = 0
)
: base_type(impl::adl_begin(r), impl::adl_end(r))
{
}
template<class SinglePassRange>
iterator_range(
SinglePassRange& r,
BOOST_DEDUCED_TYPENAME ::boost::enable_if<
is_compatible_range<SinglePassRange>
>::type* = 0
)
: base_type(impl::adl_begin(r), impl::adl_end(r))
{
}
template<class SinglePassRange>
iterator_range(const SinglePassRange& r,
iterator_range_detail::const_range_tag)
: base_type(impl::adl_begin(r), impl::adl_end(r))
{
}
template<class SinglePassRange>
iterator_range(SinglePassRange& r,
iterator_range_detail::range_tag)
: base_type(impl::adl_begin(r), impl::adl_end(r))
{
}
template<class Iterator>
iterator_range& operator=(const iterator_range<Iterator>& other)
{
this->assign(other.begin(), other.end());
return *this;
}
template<class Iterator>
iterator_range& operator=(iterator_range<Iterator>& other)
{
this->assign(other.begin(), other.end());
return *this;
}
template<class SinglePassRange>
iterator_range& operator=(SinglePassRange& r)
{
this->assign(r);
return *this;
}
template<class SinglePassRange>
iterator_range& operator=(const SinglePassRange& r)
{
this->assign(r);
return *this;
}
iterator_range& advance_begin(
BOOST_DEDUCED_TYPENAME base_type::difference_type n)
{
std::advance(this->m_Begin, n);
return *this;
}
iterator_range& advance_end(
BOOST_DEDUCED_TYPENAME base_type::difference_type n)
{
std::advance(this->m_End, n);
return *this;
}
protected:
//
// Allow subclasses an easy way to access the
// base type
//
typedef iterator_range iterator_range_;
};
// iterator range free-standing operators ---------------------------//
/////////////////////////////////////////////////////////////////////
// comparison operators
/////////////////////////////////////////////////////////////////////
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator==( const ForwardRange& l, const iterator_range<IteratorT>& r )
{
return boost::equal( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator!=( const ForwardRange& l, const iterator_range<IteratorT>& r )
{
return !boost::equal( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator<( const ForwardRange& l, const iterator_range<IteratorT>& r )
{
return iterator_range_detail::less_than( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator<=( const ForwardRange& l, const iterator_range<IteratorT>& r )
{
return iterator_range_detail::less_or_equal_than( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator>( const ForwardRange& l, const iterator_range<IteratorT>& r )
{
return iterator_range_detail::greater_than( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator>=( const ForwardRange& l, const iterator_range<IteratorT>& r )
{
return iterator_range_detail::greater_or_equal_than( l, r );
}
#ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
#else
template< class Iterator1T, class Iterator2T >
inline bool
operator==( const iterator_range<Iterator1T>& l, const iterator_range<Iterator2T>& r )
{
return boost::equal( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator==( const iterator_range<IteratorT>& l, const ForwardRange& r )
{
return boost::equal( l, r );
}
template< class Iterator1T, class Iterator2T >
inline bool
operator!=( const iterator_range<Iterator1T>& l, const iterator_range<Iterator2T>& r )
{
return !boost::equal( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator!=( const iterator_range<IteratorT>& l, const ForwardRange& r )
{
return !boost::equal( l, r );
}
template< class Iterator1T, class Iterator2T >
inline bool
operator<( const iterator_range<Iterator1T>& l, const iterator_range<Iterator2T>& r )
{
return iterator_range_detail::less_than( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator<( const iterator_range<IteratorT>& l, const ForwardRange& r )
{
return iterator_range_detail::less_than( l, r );
}
template< class Iterator1T, class Iterator2T >
inline bool
operator<=( const iterator_range<Iterator1T>& l, const iterator_range<Iterator2T>& r )
{
return iterator_range_detail::less_or_equal_than( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator<=( const iterator_range<IteratorT>& l, const ForwardRange& r )
{
return iterator_range_detail::less_or_equal_than( l, r );
}
template< class Iterator1T, class Iterator2T >
inline bool
operator>( const iterator_range<Iterator1T>& l, const iterator_range<Iterator2T>& r )
{
return iterator_range_detail::greater_than( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator>( const iterator_range<IteratorT>& l, const ForwardRange& r )
{
return iterator_range_detail::greater_than( l, r );
}
template< class Iterator1T, class Iterator2T >
inline bool
operator>=( const iterator_range<Iterator1T>& l, const iterator_range<Iterator2T>& r )
{
return iterator_range_detail::greater_or_equal_than( l, r );
}
template< class IteratorT, class ForwardRange >
inline BOOST_DEDUCED_TYPENAME boost::enable_if<
mpl::not_<boost::is_base_and_derived<iterator_range_detail::iterator_range_tag, ForwardRange> >,
bool
>::type
operator>=( const iterator_range<IteratorT>& l, const ForwardRange& r )
{
return iterator_range_detail::greater_or_equal_than( l, r );
}
#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
// iterator range utilities -----------------------------------------//
//! iterator_range construct helper
/*!
Construct an \c iterator_range from a pair of iterators
\param Begin A begin iterator
\param End An end iterator
\return iterator_range object
*/
template< typename IteratorT >
inline iterator_range< IteratorT >
make_iterator_range( IteratorT Begin, IteratorT End )
{
return iterator_range<IteratorT>( Begin, End );
}
template<typename IteratorT, typename IntegerT>
inline iterator_range<IteratorT>
make_iterator_range_n(IteratorT first, IntegerT n)
{
return iterator_range<IteratorT>(first, boost::next(first, n));
}
#ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
template< typename Range >
inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<Range>::type >
make_iterator_range( Range& r )
{
return iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<Range>::type >
( boost::begin( r ), boost::end( r ) );
}
#else
//! iterator_range construct helper
/*!
Construct an \c iterator_range from a \c Range containing the begin
and end iterators.
*/
template< class ForwardRange >
inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<ForwardRange>::type >
make_iterator_range( ForwardRange& r )
{
return iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<ForwardRange>::type >
( r, iterator_range_detail::range_tag() );
}
template< class ForwardRange >
inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<const ForwardRange>::type >
make_iterator_range( const ForwardRange& r )
{
return iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<const ForwardRange>::type >
( r, iterator_range_detail::const_range_tag() );
}
#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
namespace iterator_range_detail
{
template< class Range >
inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<Range>::type >
make_range_impl( Range& r,
BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
{
//
// Not worth the effort
//
//if( advance_begin == 0 && advance_end == 0 )
// return make_iterator_range( r );
//
BOOST_DEDUCED_TYPENAME range_iterator<Range>::type
new_begin = boost::begin( r ),
new_end = boost::end( r );
std::advance( new_begin, advance_begin );
std::advance( new_end, advance_end );
return make_iterator_range( new_begin, new_end );
}
}
#ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
template< class Range >
inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<Range>::type >
make_iterator_range( Range& r,
BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
{
return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
}
#else
template< class Range >
inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<Range>::type >
make_iterator_range( Range& r,
BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
{
return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
}
template< class Range >
inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<const Range>::type >
make_iterator_range( const Range& r,
BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
{
return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
}
#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
//! copy a range into a sequence
/*!
Construct a new sequence of the specified type from the elements
in the given range
\param Range An input range
\return New sequence
*/
template< typename SeqT, typename Range >
inline SeqT copy_range( const Range& r )
{
return SeqT( boost::begin( r ), boost::end( r ) );
}
} // namespace 'boost'
#if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1500))
#pragma warning( pop )
#endif
#endif