3 // Copyright Thorsten Ottosen & Pavol Droba 2003-2004. Use, modification and
4 // distribution is subject to the Boost Software License, Version
5 // 1.0. (See accompanying file LICENSE_1_0.txt or copy at
6 // http://www.boost.org/LICENSE_1_0.txt)
8 // For more information, see http://www.boost.org/libs/range/
11 #ifndef BOOST_RANGE_ITERATOR_RANGE_HPP
12 #define BOOST_RANGE_ITERATOR_RANGE_HPP
14 // From boost/dynamic_bitset.hpp; thanks to Matthias Troyer for Cray X1 patch.
15 #include <boost/config.hpp> // Define __STL_CONFIG_H, if appropriate.
16 #ifndef BOOST_OLD_IOSTREAMS
17 # if defined(__STL_CONFIG_H) && \
18 !defined (__STL_USE_NEW_IOSTREAMS) && !defined(__crayx1) \
20 # define BOOST_OLD_IOSTREAMS
22 #endif // #ifndef BOOST_OLD_IOSTREAMS
24 #include <boost/detail/workaround.hpp>
25 #include <boost/range/functions.hpp>
26 #include <boost/range/result_iterator.hpp>
27 #include <boost/range/difference_type.hpp>
28 #include <boost/iterator/iterator_traits.hpp>
29 #include <boost/assert.hpp>
32 #ifndef BOOST_OLD_IOSTREAMS
41 Defines the \c iterator_class and related functions.
42 \c iterator_range is a simple wrapper of iterator pair idiom. It provides
43 a rich subset of Container interface.
49 namespace iterator_range_detail
52 // The functions adl_begin and adl_end are implemented in a separate
55 template<typename IteratorT>
56 struct iterator_range_impl {
57 template< class ForwardRange >
58 static IteratorT adl_begin( ForwardRange& r )
60 return IteratorT( boost::begin( r ) );
63 template< class ForwardRange >
64 static IteratorT adl_end( ForwardRange& r )
66 return IteratorT( boost::end( r ) );
70 template< class Left, class Right >
71 inline bool equal( const Left& l, const Right& r )
73 typedef BOOST_DEDUCED_TYPENAME boost::range_size<Left>::type sz_type;
75 sz_type l_size = boost::size( l ),
76 r_size = boost::size( r );
78 if( l_size != r_size )
81 return std::equal( boost::begin(l), boost::end(l),
85 template< class Left, class Right >
86 inline bool less_than( const Left& l, const Right& r )
88 return std::lexicographical_compare( boost::begin(l),
95 struct const_range_tag { };
99 // iterator range template class -----------------------------------------//
101 //! iterator_range class
103 An \c iterator_range delimits a range in a sequence by beginning and ending iterators.
104 An iterator_range can be passed to an algorithm which requires a sequence as an input.
105 For example, the \c toupper() function may be used most frequently on strings,
106 but can also be used on iterator_ranges:
109 boost::tolower( find( s, "UPPERCASE STRING" ) );
112 Many algorithms working with sequences take a pair of iterators,
113 delimiting a working range, as an arguments. The \c iterator_range class is an
114 encapsulation of a range identified by a pair of iterators.
115 It provides a collection interface,
116 so it is possible to pass an instance to an algorithm requiring a collection as an input.
118 template<typename IteratorT>
121 protected: // Used by sub_range
122 //! implementation class
123 typedef iterator_range_detail::iterator_range_impl<IteratorT> impl;
127 typedef iterator_range<IteratorT> type;
128 //BOOST_BROKEN_COMPILER_TYPE_TRAITS_SPECIALIZATION(value_type);
130 //! Encapsulated value type
131 typedef BOOST_DEDUCED_TYPENAME
132 iterator_value<IteratorT>::type value_type;
135 typedef BOOST_DEDUCED_TYPENAME
136 iterator_difference<IteratorT>::type difference_type;
139 typedef std::size_t size_type; // note: must be unsigned
142 typedef iterator_range<IteratorT> this_type;
146 // Needed because value-type is the same for
147 // const and non-const iterators
149 typedef BOOST_DEDUCED_TYPENAME
150 iterator_reference<IteratorT>::type reference;
152 //! const_iterator type
154 There is no distinction between const_iterator and iterator.
155 These typedefs are provides to fulfill container interface
157 typedef IteratorT const_iterator;
159 typedef IteratorT iterator;
161 iterator_range() : m_Begin( iterator() ), m_End( iterator() ),
165 #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
166 iterator_range( this_type r ) :
167 : m_Begin(r.begin()), m_End(r.end())
170 this_type& operator=( this_type r )
178 //! Constructor from a pair of iterators
179 template< class Iterator >
180 iterator_range( Iterator Begin, Iterator End ) :
181 m_Begin(Begin), m_End(End), singular(false) {}
183 //! Constructor from a Range
184 template< class Range >
185 iterator_range( const Range& r ) :
186 m_Begin( impl::adl_begin( r ) ), m_End( impl::adl_end( r ) ),
189 //! Constructor from a Range
190 template< class Range >
191 iterator_range( Range& r ) :
192 m_Begin( impl::adl_begin( r ) ), m_End( impl::adl_end( r ) ),
195 //! Constructor from a Range
196 template< class Range >
197 iterator_range( const Range& r, iterator_range_detail::const_range_tag ) :
198 m_Begin( impl::adl_begin( r ) ), m_End( impl::adl_end( r ) ),
201 //! Constructor from a Range
202 template< class Range >
203 iterator_range( Range& r, iterator_range_detail::range_tag ) :
204 m_Begin( impl::adl_begin( r ) ), m_End( impl::adl_end( r ) ),
207 #if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
208 this_type& operator=( const this_type& r )
213 // remark: this need not necessarily be true, but it does no harm
215 singular = r.singular;
220 template< class Iterator >
221 iterator_range& operator=( const iterator_range<Iterator>& r )
226 // remark: this need not necessarily be true, but it does no harm
228 singular = r.empty();
232 template< class ForwardRange >
233 iterator_range& operator=( ForwardRange& r )
235 m_Begin = impl::adl_begin( r );
236 m_End = impl::adl_end( r );
241 template< class ForwardRange >
242 iterator_range& operator=( const ForwardRange& r )
244 m_Begin = impl::adl_begin( r );
245 m_End = impl::adl_end( r );
250 IteratorT begin() const
255 IteratorT end() const
260 size_type size() const
265 #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x582))
266 return std::distance<IteratorT>( m_Begin, m_End );
268 return std::distance( m_Begin, m_End );
277 return m_Begin == m_End;
280 #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
281 operator bool() const
286 typedef iterator (iterator_range::*unspecified_bool_type) () const;
287 operator unspecified_bool_type() const
289 return empty() ? 0: &iterator_range::end;
293 bool equal( const iterator_range& r ) const
295 return singular == r.singular && m_Begin == r.m_Begin && m_End == r.m_End;
299 #ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
301 bool operator==( const iterator_range& r ) const
303 return iterator_range_detail::equal( *this, r );
306 bool operator!=( const iterator_range& r ) const
308 return !operator==(r);
311 bool operator<( const iterator_range& r ) const
313 return iterator_range_detail::less_than( *this, r );
318 public: // convenience
319 reference front() const
321 BOOST_ASSERT( !empty() );
325 reference back() const
327 BOOST_ASSERT( !empty() );
328 IteratorT last( m_End );
332 reference operator[]( size_type sz ) const
334 //BOOST_STATIC_ASSERT( is_random_access );
335 BOOST_ASSERT( sz < size() );
339 iterator_range& advance_begin( difference_type n )
341 std::advance( m_Begin, n );
345 iterator_range& advance_end( difference_type n )
347 std::advance( m_End, n );
352 // begin and end iterators
358 // iterator range free-standing operators ---------------------------//
360 #ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
362 template< class Iterator >
363 inline bool empty( const iterator_range<Iterator>& r )
366 // this will preserve the well-defined empty() even
367 // though 'r' is singular.
373 #ifndef BOOST_OLD_IOSTREAMS
375 //! iterator_range output operator
377 Output the range to an ostream. Elements are outputed
378 in a sequence without separators.
380 template< typename IteratorT, typename Elem, typename Traits >
381 inline std::basic_ostream<Elem,Traits>& operator<<(
382 std::basic_ostream<Elem, Traits>& Os,
383 const iterator_range<IteratorT>& r )
385 std::copy( r.begin(), r.end(),
386 std::ostream_iterator< BOOST_DEDUCED_TYPENAME
387 iterator_value<IteratorT>::type,
394 //! iterator_range output operator
396 Output the range to an ostream. Elements are outputed
397 in a sequence without separators.
399 template< typename IteratorT >
400 inline std::ostream& operator<<(
402 const iterator_range<IteratorT>& r )
404 std::copy( r.begin(), r.end(), std::ostream_iterator<char>(Os));
410 /////////////////////////////////////////////////////////////////////
411 // comparison operators
412 /////////////////////////////////////////////////////////////////////
414 template< class IteratorT, class ForwardRange >
415 inline bool operator==( const ForwardRange& l,
416 const iterator_range<IteratorT>& r )
418 return iterator_range_detail::equal( l, r );
421 template< class IteratorT, class ForwardRange >
422 inline bool operator!=( const ForwardRange& l,
423 const iterator_range<IteratorT>& r )
425 return !iterator_range_detail::equal( l, r );
428 template< class IteratorT, class ForwardRange >
429 inline bool operator<( const ForwardRange& l,
430 const iterator_range<IteratorT>& r )
432 return iterator_range_detail::less_than( l, r );
435 #ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
437 template< class Iterator1T, class Iterator2T >
438 inline bool operator==( const iterator_range<Iterator1T>& l,
439 const iterator_range<Iterator2T>& r )
441 return iterator_range_detail::equal( l, r );
444 template< class IteratorT, class ForwardRange >
445 inline bool operator==( const iterator_range<IteratorT>& l,
446 const ForwardRange& r )
448 return iterator_range_detail::equal( l, r );
452 template< class Iterator1T, class Iterator2T >
453 inline bool operator!=( const iterator_range<Iterator1T>& l,
454 const iterator_range<Iterator2T>& r )
456 return !iterator_range_detail::equal( l, r );
459 template< class IteratorT, class ForwardRange >
460 inline bool operator!=( const iterator_range<IteratorT>& l,
461 const ForwardRange& r )
463 return !iterator_range_detail::equal( l, r );
467 template< class Iterator1T, class Iterator2T >
468 inline bool operator<( const iterator_range<Iterator1T>& l,
469 const iterator_range<Iterator2T>& r )
471 return iterator_range_detail::less_than( l, r );
474 template< class IteratorT, class ForwardRange >
475 inline bool operator<( const iterator_range<IteratorT>& l,
476 const ForwardRange& r )
478 return iterator_range_detail::less_than( l, r );
481 #endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
483 // iterator range utilities -----------------------------------------//
485 //! iterator_range construct helper
487 Construct an \c iterator_range from a pair of iterators
489 \param Begin A begin iterator
490 \param End An end iterator
491 \return iterator_range object
493 template< typename IteratorT >
494 inline iterator_range< IteratorT >
495 make_iterator_range( IteratorT Begin, IteratorT End )
497 return iterator_range<IteratorT>( Begin, End );
500 #ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
502 template< typename Range >
503 inline iterator_range< BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type >
504 make_iterator_range( Range& r )
506 return iterator_range< BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type >
507 ( boost::begin( r ), boost::end( r ) );
511 //! iterator_range construct helper
513 Construct an \c iterator_range from a \c Range containing the begin
516 template< class ForwardRange >
517 inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<ForwardRange>::type >
518 make_iterator_range( ForwardRange& r )
520 return iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<ForwardRange>::type >
521 ( r, iterator_range_detail::range_tag() );
524 template< class ForwardRange >
525 inline iterator_range< BOOST_DEDUCED_TYPENAME range_const_iterator<ForwardRange>::type >
526 make_iterator_range( const ForwardRange& r )
528 return iterator_range< BOOST_DEDUCED_TYPENAME range_const_iterator<ForwardRange>::type >
529 ( r, iterator_range_detail::const_range_tag() );
532 #endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
534 namespace iterator_range_detail
536 template< class Range >
537 inline iterator_range< BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type >
538 make_range_impl( Range& r,
539 BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
540 BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
542 if( advance_begin == 0 && advance_end == 0 )
543 return make_iterator_range( r );
545 BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type
546 new_begin = boost::begin( r ),
547 new_end = boost::end( r );
548 std::advance( new_begin, advance_begin );
549 std::advance( new_end, advance_end );
550 return make_iterator_range( new_begin, new_end );
554 #ifdef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
556 template< class Range >
557 inline iterator_range< BOOST_DEDUCED_TYPENAME range_result_iterator<Range>::type >
558 make_iterator_range( Range& r,
559 BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
560 BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
562 //BOOST_ASSERT( advance_begin - advance_end <= size(r) && "creating invalid range" );
563 return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
568 template< class Range >
569 inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<Range>::type >
570 make_iterator_range( Range& r,
571 BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
572 BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
574 //BOOST_ASSERT( advance_begin - advance_end <= size(r) && "creating invalid range" );
575 return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
578 template< class Range >
579 inline iterator_range< BOOST_DEDUCED_TYPENAME range_const_iterator<Range>::type >
580 make_iterator_range( const Range& r,
581 BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_begin,
582 BOOST_DEDUCED_TYPENAME range_difference<Range>::type advance_end )
584 //BOOST_ASSERT( advance_begin - advance_end <= size(r) && "creating invalid range" );
585 return iterator_range_detail::make_range_impl( r, advance_begin, advance_end );
588 #endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
590 //! copy a range into a sequence
592 Construct a new sequence of the specified type from the elements
595 \param Range An input range
598 template< typename SeqT, typename Range >
599 inline SeqT copy_range( const Range& r )
601 return SeqT( boost::begin( r ), boost::end( r ) );
604 } // namespace 'boost'
606 #undef BOOST_OLD_IOSTREAMS