3 #ifndef __CDS_CONTAINER_SPLIT_LIST_SET_H
4 #define __CDS_CONTAINER_SPLIT_LIST_SET_H
6 #include <cds/intrusive/split_list.h>
7 #include <cds/container/details/make_split_list_set.h>
8 #include <cds/details/functor_wrapper.h>
10 namespace cds { namespace container {
12 /// Split-ordered list set
13 /** @ingroup cds_nonintrusive_set
14 \anchor cds_nonintrusive_SplitListSet_hp
16 Hash table implementation based on split-ordered list algorithm discovered by Ori Shalev and Nir Shavit, see
17 - [2003] Ori Shalev, Nir Shavit "Split-Ordered Lists - Lock-free Resizable Hash Tables"
18 - [2008] Nir Shavit "The Art of Multiprocessor Programming"
20 See intrusive::SplitListSet for a brief description of the split-list algorithm.
23 - \p GC - Garbage collector used
24 - \p T - type stored in the split-list. The type must be default- and copy-constructible.
25 - \p Traits - type traits, default is split_list::type_traits. Instead of declaring split_list::type_traits -based
26 struct you may apply option-based notation with split_list::make_traits metafunction.
28 There are the specializations:
29 - for \ref cds_urcu_desc "RCU" - declared in <tt>cd/container/split_list_set_rcu.h</tt>,
30 see \ref cds_nonintrusive_SplitListSet_rcu "SplitListSet<RCU>".
31 - for \ref cds::gc::nogc declared in <tt>cds/container/split_list_set_nogc.h</tt>,
32 see \ref cds_nonintrusive_SplitListSet_nogc "SplitListSet<gc::nogc>".
36 You should decide what garbage collector you want, and what ordered list you want to use. Split-ordered list
37 is original data structure based on an ordered list. Suppose, you want construct split-list set based on gc::PTB GC
38 and LazyList as ordered list implementation. So, you beginning your program with following include:
40 #include <cds/container/lazy_list_ptb.h>
41 #include <cds/container/split_list_set.h>
43 namespace cc = cds::container;
45 // The data belonged to split-ordered list
47 int nKey; // key field
48 std::string strValue ; // value field
51 The inclusion order is important: first, include header for ordered-list implementation (for this example, <tt>cds/container/lazy_list_ptb.h</tt>),
52 then the header for split-list set <tt>cds/container/split_list_set.h</tt>.
54 Now, you should declare traits for split-list set. The main parts of traits are a hash functor for the set and a comparing functor for ordered list.
55 Note that we define several function in <tt>foo_hash</tt> and <tt>foo_less</tt> functors for different argument types since we want call our \p %SplitListSet
56 object by the key of type <tt>int</tt> and by the value of type <tt>foo</tt>.
58 The second attention: instead of using \p %LazyList in \p %SplitListSet traits we use a tag <tt>cds::contaner::lazy_list_tag</tt> for the lazy list.
59 The split-list requires significant support from underlying ordered list class and it is not good idea to dive you
60 into deep implementation details of split-list and ordered list interrelations. The tag paradigm simplifies split-list interface.
65 size_t operator()( int key ) const { return std::hash( key ) ; }
66 size_t operator()( foo const& item ) const { return std::hash( item.nKey ) ; }
71 bool operator()(int i, foo const& f ) const { return i < f.nKey ; }
72 bool operator()(foo const& f, int i ) const { return f.nKey < i ; }
73 bool operator()(foo const& f1, foo const& f2) const { return f1.nKey < f2.nKey; }
76 // SplitListSet traits
77 struct foo_set_traits: public cc::split_list::type_traits
79 typedef cc::lazy_list_tag ordered_list ; // what type of ordered list we want to use
80 typedef foo_hash hash ; // hash functor for our data stored in split-list set
82 // Type traits for our LazyList class
83 struct ordered_list_traits: public cc::lazy_list::type_traits
85 typedef foo_less less ; // use our foo_less as comparator to order list nodes
90 Now you are ready to declare our set class based on \p %SplitListSet:
92 typedef cc::SplitListSet< cds::gc::PTB, foo, foo_set_traits > foo_set;
95 You may use the modern option-based declaration instead of classic type-traits-based one:
97 typedef cc:SplitListSet<
98 cs::gc::PTB // GC used
99 ,foo // type of data stored
100 ,cc::split_list::make_traits< // metafunction to build split-list traits
101 cc::split_list::ordered_list<cc::lazy_list_tag> // tag for underlying ordered list implementation
102 ,cc::opt::hash< foo_hash > // hash functor
103 ,cc::split_list::ordered_list_traits< // ordered list traits desired
104 cc::lazy_list::make_traits< // metafunction to build lazy list traits
105 cc::opt::less< foo_less > // less-based compare functor
111 In case of option-based declaration using split_list::make_traits metafunction
112 the struct \p foo_set_traits is not required.
114 Now, the set of type \p foo_set is ready to use in your program.
116 Note that in this example we show only mandatory type_traits parts, optional ones is the default and they are inherited
117 from cds::container::split_list::type_traits.
118 The <b>cds</b> library contains many other options for deep tuning of behavior of the split-list and
119 ordered-list containers.
124 #ifdef CDS_DOXYGEN_INVOKED
125 class Traits = split_list::type_traits
131 #ifdef CDS_DOXYGEN_INVOKED
132 protected intrusive::SplitListSet<GC, typename Traits::ordered_list, Traits>
134 protected details::make_split_list_set< GC, T, typename Traits::ordered_list, split_list::details::wrap_set_traits<T, Traits> >::type
139 typedef details::make_split_list_set< GC, T, typename Traits::ordered_list, split_list::details::wrap_set_traits<T, Traits> > maker;
140 typedef typename maker::type base_class;
144 typedef Traits options ; ///< \p Traits template argument
145 typedef typename maker::gc gc ; ///< Garbage collector
146 typedef typename maker::value_type value_type ; ///< type of value stored in the list
147 typedef typename maker::ordered_list ordered_list ; ///< Underlying ordered list class
148 typedef typename base_class::key_comparator key_comparator; ///< key compare functor
150 /// Hash functor for \p %value_type and all its derivatives that you use
151 typedef typename base_class::hash hash;
152 typedef typename base_class::item_counter item_counter ; ///< Item counter type
156 typedef typename maker::cxx_node_allocator cxx_node_allocator;
157 typedef typename maker::node_type node_type;
162 typedef cds::gc::guarded_ptr< gc, node_type, value_type, details::guarded_ptr_cast_set<node_type, value_type> > guarded_ptr;
166 template <typename Q>
167 static node_type * alloc_node(Q const& v )
169 return cxx_node_allocator().New( v );
172 template <typename Q, typename Func>
173 bool find_( Q& val, Func f )
175 # ifdef CDS_CXX11_LAMBDA_SUPPORT
176 return base_class::find( val, [&f]( node_type& item, Q& val ) { cds::unref(f)(item.m_Value, val) ; } );
178 find_functor_wrapper<Func> fw(f);
179 return base_class::find( val, cds::ref(fw) );
183 template <typename Q, typename Less, typename Func>
184 bool find_with_( Q& val, Less pred, Func f )
186 # ifdef CDS_CXX11_LAMBDA_SUPPORT
187 return base_class::find_with( val, typename maker::template predicate_wrapper<Less>::type(),
188 [&f]( node_type& item, Q& val ) { cds::unref(f)(item.m_Value, val) ; } );
190 find_functor_wrapper<Func> fw(f);
191 return base_class::find_with( val, typename maker::template predicate_wrapper<Less>::type(), cds::ref(fw) );
195 # ifdef CDS_EMPLACE_SUPPORT
196 template <typename... Args>
197 static node_type * alloc_node( Args&&... args )
199 return cxx_node_allocator().MoveNew( std::forward<Args>(args)...);
203 static void free_node( node_type * pNode )
205 cxx_node_allocator().Delete( pNode );
208 struct node_disposer {
209 void operator()( node_type * pNode )
214 typedef std::unique_ptr< node_type, node_disposer > scoped_node_ptr;
216 bool insert_node( node_type * pNode )
218 assert( pNode != nullptr );
219 scoped_node_ptr p(pNode);
221 if ( base_class::insert( *pNode ) ) {
233 # ifndef CDS_CXX11_LAMBDA_SUPPORT
234 template <typename Func>
235 class insert_functor_wrapper: protected cds::details::functor_wrapper<Func>
237 typedef cds::details::functor_wrapper<Func> base_class;
239 insert_functor_wrapper( Func f ): base_class(f) {}
241 void operator()(node_type& node)
243 base_class::get()( node.m_Value );
247 template <typename Func, typename Q>
248 class ensure_functor_wrapper: protected cds::details::functor_wrapper<Func>
250 typedef cds::details::functor_wrapper<Func> base_class;
253 ensure_functor_wrapper( Func f, Q const& v ): base_class(f), m_val(v) {}
255 void operator()( bool bNew, node_type& item, node_type const& /*val*/ )
257 base_class::get()( bNew, item.m_Value, m_val );
261 template <typename Func>
262 class find_functor_wrapper: protected cds::details::functor_wrapper<Func>
264 typedef cds::details::functor_wrapper<Func> base_class;
266 find_functor_wrapper( Func f ): base_class(f) {}
268 template <typename Q>
269 void operator()( node_type& item, Q& val )
271 base_class::get()( item.m_Value, val );
275 template <typename Func>
276 class erase_functor_wrapper: protected cds::details::functor_wrapper<Func>
278 typedef cds::details::functor_wrapper<Func> base_class;
280 erase_functor_wrapper( Func f ): base_class( f ) {}
282 void operator()(node_type& node)
284 base_class::get()( node.m_Value );
287 # endif // ifndef CDS_CXX11_LAMBDA_SUPPORT
293 \p IsConst - constness boolean flag
295 The forward iterator for a split-list has the following features:
296 - it has no post-increment operator
297 - it depends on underlying ordered list iterator
298 - The iterator object cannot be moved across thread boundary since it contains GC's guard that is thread-private GC data.
299 - Iterator ensures thread-safety even if you delete the item that iterator points to. However, in case of concurrent
300 deleting operations it is no guarantee that you iterate all item in the split-list.
302 Therefore, the use of iterators in concurrent environment is not good idea. Use it for debug purpose only.
304 template <bool IsConst>
305 class iterator_type: protected base_class::template iterator_type<IsConst>
308 typedef typename base_class::template iterator_type<IsConst> iterator_base_class;
309 friend class SplitListSet;
312 /// Value pointer type (const for const iterator)
313 typedef typename cds::details::make_const_type<value_type, IsConst>::pointer value_ptr;
314 /// Value reference type (const for const iterator)
315 typedef typename cds::details::make_const_type<value_type, IsConst>::reference value_ref;
323 iterator_type( iterator_type const& src )
324 : iterator_base_class( src )
329 explicit iterator_type( iterator_base_class const& src )
330 : iterator_base_class( src )
335 /// Dereference operator
336 value_ptr operator ->() const
338 return &(iterator_base_class::operator->()->m_Value);
341 /// Dereference operator
342 value_ref operator *() const
344 return iterator_base_class::operator*().m_Value;
348 iterator_type& operator ++()
350 iterator_base_class::operator++();
354 /// Assignment operator
355 iterator_type& operator = (iterator_type const& src)
357 iterator_base_class::operator=(src);
361 /// Equality operator
363 bool operator ==(iterator_type<C> const& i ) const
365 return iterator_base_class::operator==(i);
368 /// Equality operator
370 bool operator !=(iterator_type<C> const& i ) const
372 return iterator_base_class::operator!=(i);
377 /// Initializes split-ordered list of default capacity
379 The default capacity is defined in bucket table constructor.
380 See intrusive::split_list::expandable_bucket_table, intrusive::split_list::static_bucket_table
381 which selects by intrusive::split_list::dynamic_bucket_table option.
387 /// Initializes split-ordered list
389 size_t nItemCount ///< estimate average of item count
390 , size_t nLoadFactor = 1 ///< load factor - average item count per bucket. Small integer up to 8, default is 1.
392 : base_class( nItemCount, nLoadFactor )
397 typedef iterator_type<false> iterator;
399 /// Const forward iterator
400 typedef iterator_type<true> const_iterator;
402 /// Returns a forward iterator addressing the first element in a set
404 For empty set \code begin() == end() \endcode
408 return iterator( base_class::begin() );
411 /// Returns an iterator that addresses the location succeeding the last element in a set
413 Do not use the value returned by <tt>end</tt> function to access any item.
414 The returned value can be used only to control reaching the end of the set.
415 For empty set \code begin() == end() \endcode
419 return iterator( base_class::end() );
422 /// Returns a forward const iterator addressing the first element in a set
423 const_iterator begin() const
425 return const_iterator( base_class::begin() );
428 /// Returns an const iterator that addresses the location succeeding the last element in a set
429 const_iterator end() const
431 return const_iterator( base_class::end() );
437 The function creates a node with copy of \p val value
438 and then inserts the node created into the set.
440 The type \p Q should contain as minimum the complete key for the node.
441 The object of \ref value_type should be constructible from a value of type \p Q.
442 In trivial case, \p Q is equal to \ref value_type.
444 Returns \p true if \p val is inserted into the set, \p false otherwise.
446 template <typename Q>
447 bool insert( Q const& val )
449 return insert_node( alloc_node( val ) );
454 The function allows to split creating of new item into two part:
455 - create item with key only
456 - insert new item into the set
457 - if inserting is success, calls \p f functor to initialize value-field of \p val.
459 The functor signature is:
461 void func( value_type& val );
463 where \p val is the item inserted. User-defined functor \p f should guarantee that during changing
464 \p val no any other changes could be made on this set's item by concurrent threads.
465 The user-defined functor is called only if the inserting is success. It may be passed by reference
466 using <tt>boost::ref</tt>
468 template <typename Q, typename Func>
469 bool insert( Q const& val, Func f )
471 scoped_node_ptr pNode( alloc_node( val ));
473 # ifdef CDS_CXX11_LAMBDA_SUPPORT
474 if ( base_class::insert( *pNode, [&f](node_type& node) { cds::unref(f)( node.m_Value ) ; } ))
476 insert_functor_wrapper<Func> fw(f);
477 if ( base_class::insert( *pNode, cds::ref(fw) ) )
486 # ifdef CDS_EMPLACE_SUPPORT
487 /// Inserts data of type \p %value_type constructed with <tt>std::forward<Args>(args)...</tt>
489 Returns \p true if inserting successful, \p false otherwise.
491 @note This function is available only for compiler that supports
492 variadic template and move semantics
494 template <typename... Args>
495 bool emplace( Args&&... args )
497 return insert_node( alloc_node( std::forward<Args>(args)...));
501 /// Ensures that the \p item exists in the set
503 The operation performs inserting or changing data with lock-free manner.
505 If the \p val key not found in the set, then the new item created from \p val
506 is inserted into the set. Otherwise, the functor \p func is called with the item found.
507 The functor \p Func should be a function with signature:
509 void func( bool bNew, value_type& item, const Q& val );
514 void operator()( bool bNew, value_type& item, const Q& val );
519 - \p bNew - \p true if the item has been inserted, \p false otherwise
520 - \p item - item of the set
521 - \p val - argument \p val passed into the \p ensure function
523 The functor may change non-key fields of the \p item; however, \p func must guarantee
524 that during changing no any other modifications could be made on this item by concurrent threads.
526 You may pass \p func argument by reference using <tt>boost::ref</tt>.
528 Returns <tt> std::pair<bool, bool> </tt> where \p first is true if operation is successfull,
529 \p second is true if new item has been added or \p false if the item with \p key
530 already is in the set.
532 template <typename Q, typename Func>
533 std::pair<bool, bool> ensure( Q const& val, Func func )
535 scoped_node_ptr pNode( alloc_node( val ));
537 # ifdef CDS_CXX11_LAMBDA_SUPPORT
538 std::pair<bool, bool> bRet = base_class::ensure( *pNode,
539 [&func, &val]( bool bNew, node_type& item, node_type const& /*val*/ ) {
540 cds::unref(func)( bNew, item.m_Value, val );
543 ensure_functor_wrapper<Func, Q> fw( func, val );
544 std::pair<bool, bool> bRet = base_class::ensure( *pNode, cds::ref(fw) );
547 if ( bRet.first && bRet.second )
552 /// Deletes \p key from the set
553 /** \anchor cds_nonintrusive_SplitListSet_erase_val
555 The item comparator should be able to compare the values of type \p value_type
558 Return \p true if key is found and deleted, \p false otherwise
560 template <typename Q>
561 bool erase( Q const& key )
563 return base_class::erase( key );
566 /// Deletes the item from the set using \p pred predicate for searching
568 The function is an analog of \ref cds_nonintrusive_SplitListSet_erase_val "erase(Q const&)"
569 but \p pred is used for key comparing.
570 \p Less functor has the interface like \p std::less.
571 \p Less must imply the same element order as the comparator used for building the set.
573 template <typename Q, typename Less>
574 bool erase_with( Q const& key, Less pred )
576 return base_class::erase_with( key, typename maker::template predicate_wrapper<Less>::type() );
579 /// Deletes \p key from the set
580 /** \anchor cds_nonintrusive_SplitListSet_erase_func
582 The function searches an item with key \p key, calls \p f functor
583 and deletes the item. If \p key is not found, the functor is not called.
585 The functor \p Func interface:
588 void operator()(value_type const& val);
591 The functor may be passed by reference using <tt>boost:ref</tt>
593 Since the key of SplitListSet's \p value_type is not explicitly specified,
594 template parameter \p Q defines the key type searching in the list.
595 The list item comparator should be able to compare the values of the type \p value_type
598 Return \p true if key is found and deleted, \p false otherwise
600 template <typename Q, typename Func>
601 bool erase( Q const& key, Func f )
603 # ifdef CDS_CXX11_LAMBDA_SUPPORT
604 return base_class::erase( key, [&f](node_type& node) { cds::unref(f)( node.m_Value ); } );
606 erase_functor_wrapper<Func> fw( f );
607 return base_class::erase( key, cds::ref(fw) );
611 /// Deletes the item from the set using \p pred predicate for searching
613 The function is an analog of \ref cds_nonintrusive_SplitListSet_erase_func "erase(Q const&, Func)"
614 but \p pred is used for key comparing.
615 \p Less functor has the interface like \p std::less.
616 \p Less must imply the same element order as the comparator used for building the set.
618 template <typename Q, typename Less, typename Func>
619 bool erase_with( Q const& key, Less pred, Func f )
621 # ifdef CDS_CXX11_LAMBDA_SUPPORT
622 return base_class::erase_with( key, typename maker::template predicate_wrapper<Less>::type(),
623 [&f](node_type& node) { cds::unref(f)( node.m_Value ); } );
625 erase_functor_wrapper<Func> fw( f );
626 return base_class::erase_with( key, typename maker::template predicate_wrapper<Less>::type(), cds::ref(fw) );
630 /// Extracts the item with specified \p key
631 /** \anchor cds_nonintrusive_SplitListSet_hp_extract
632 The function searches an item with key equal to \p key,
633 unlinks it from the set, and returns it in \p dest parameter.
634 If the item with key equal to \p key is not found the function returns \p false.
636 Note the compare functor should accept a parameter of type \p Q that may be not the same as \p value_type.
638 The extracted item is freed automatically when returned \ref guarded_ptr object will be destroyed or released.
639 @note Each \p guarded_ptr object uses the GC's guard that can be limited resource.
643 typedef cds::container::SplitListSet< your_template_args > splitlist_set;
644 splitlist_set theSet;
647 splitlist_set::guarded_ptr gp;
648 theSet.extract( gp, 5 );
652 // Destructor of gp releases internal HP guard
656 template <typename Q>
657 bool extract( guarded_ptr& dest, Q const& key )
659 return extract_( dest.guard(), key );
662 /// Extracts the item using compare functor \p pred
664 The function is an analog of \ref cds_nonintrusive_SplitListSet_hp_extract "extract(guarded_ptr&, Q const&)"
665 but \p pred predicate is used for key comparing.
667 \p Less functor has the semantics like \p std::less but should take arguments of type \ref value_type and \p Q
669 \p pred must imply the same element order as the comparator used for building the set.
671 template <typename Q, typename Less>
672 bool extract_with( guarded_ptr& dest, Q const& key, Less pred )
674 return extract_with_( dest.guard(), key, pred );
677 /// Finds the key \p val
678 /** \anchor cds_nonintrusive_SplitListSet_find_func
680 The function searches the item with key equal to \p val and calls the functor \p f for item found.
681 The interface of \p Func functor is:
684 void operator()( value_type& item, Q& val );
687 where \p item is the item found, \p val is the <tt>find</tt> function argument.
689 You may pass \p f argument by reference using <tt>boost::ref</tt> or cds::ref.
691 The functor may change non-key fields of \p item. Note that the functor is only guarantee
692 that \p item cannot be disposed during functor is executing.
693 The functor does not serialize simultaneous access to the set's \p item. If such access is
694 possible you must provide your own synchronization schema on item level to exclude unsafe item modifications.
696 The \p val argument is non-const since it can be used as \p f functor destination i.e., the functor
697 may modify both arguments.
699 Note the hash functor specified for class \p Traits template parameter
700 should accept a parameter of type \p Q that can be not the same as \p value_type.
702 The function returns \p true if \p val is found, \p false otherwise.
704 template <typename Q, typename Func>
705 bool find( Q& val, Func f )
707 return find_( val, f );
710 /// Finds the key \p val using \p pred predicate for searching
712 The function is an analog of \ref cds_nonintrusive_SplitListSet_find_func "find(Q&, Func)"
713 but \p pred is used for key comparing.
714 \p Less functor has the interface like \p std::less.
715 \p Less must imply the same element order as the comparator used for building the set.
717 template <typename Q, typename Less, typename Func>
718 bool find_with( Q& val, Less pred, Func f )
720 return find_with_( val, pred, f );
723 /// Finds the key \p val
724 /** \anchor cds_nonintrusive_SplitListSet_find_cfunc
726 The function searches the item with key equal to \p val and calls the functor \p f for item found.
727 The interface of \p Func functor is:
730 void operator()( value_type& item, Q const& val );
733 where \p item is the item found, \p val is the <tt>find</tt> function argument.
735 You may pass \p f argument by reference using <tt>boost::ref</tt> or cds::ref.
737 The functor may change non-key fields of \p item. Note that the functor is only guarantee
738 that \p item cannot be disposed during functor is executing.
739 The functor does not serialize simultaneous access to the set's \p item. If such access is
740 possible you must provide your own synchronization schema on item level to exclude unsafe item modifications.
742 Note the hash functor specified for class \p Traits template parameter
743 should accept a parameter of type \p Q that can be not the same as \p value_type.
745 The function returns \p true if \p val is found, \p false otherwise.
747 template <typename Q, typename Func>
748 bool find( Q const& val, Func f )
750 return find_( val, f );
753 /// Finds the key \p val using \p pred predicate for searching
755 The function is an analog of \ref cds_nonintrusive_SplitListSet_find_cfunc "find(Q const&, Func)"
756 but \p pred is used for key comparing.
757 \p Less functor has the interface like \p std::less.
758 \p Less must imply the same element order as the comparator used for building the set.
760 template <typename Q, typename Less, typename Func>
761 bool find_with( Q const& val, Less pred, Func f )
763 return find_with_( val, pred, f );
766 /// Finds the key \p val
767 /** \anchor cds_nonintrusive_SplitListSet_find_val
769 The function searches the item with key equal to \p val
770 and returns \p true if it is found, and \p false otherwise.
772 Note the hash functor specified for class \p Traits template parameter
773 should accept a parameter of type \p Q that can be not the same as \ref value_type.
775 template <typename Q>
776 bool find( Q const& val )
778 return base_class::find( val );
781 /// Finds the key \p val using \p pred predicate for searching
783 The function is an analog of \ref cds_nonintrusive_SplitListSet_find_val "find(Q const&)"
784 but \p pred is used for key comparing.
785 \p Less functor has the interface like \p std::less.
786 \p Less must imply the same element order as the comparator used for building the set.
788 template <typename Q, typename Less>
789 bool find_with( Q const& val, Less pred )
791 return base_class::find_with( val, typename maker::template predicate_wrapper<Less>::type() );
794 /// Finds the key \p key and return the item found
795 /** \anchor cds_nonintrusive_SplitListSet_hp_get
796 The function searches the item with key equal to \p key
797 and assigns the item found to guarded pointer \p ptr.
798 The function returns \p true if \p key is found, and \p false otherwise.
799 If \p key is not found the \p ptr parameter is not changed.
801 @note Each \p guarded_ptr object uses one GC's guard which can be limited resource.
805 typedef cds::container::SplitListSet< your_template_params > splitlist_set;
806 splitlist_set theSet;
809 splitlist_set::guarded_ptr gp;
810 if ( theSet.get( gp, 5 )) {
814 // Destructor of guarded_ptr releases internal HP guard
818 Note the compare functor specified for split-list set
819 should accept a parameter of type \p Q that can be not the same as \p value_type.
821 template <typename Q>
822 bool get( guarded_ptr& ptr, Q const& key )
824 return get_( ptr.guard(), key );
827 /// Finds \p key and return the item found
829 The function is an analog of \ref cds_nonintrusive_SplitListSet_hp_get "get( guarded_ptr&, Q const&)"
830 but \p pred is used for comparing the keys.
832 \p Less functor has the semantics like \p std::less but should take arguments of type \ref value_type and \p Q
834 \p pred must imply the same element order as the comparator used for building the set.
836 template <typename Q, typename Less>
837 bool get_with( guarded_ptr& ptr, Q const& key, Less pred )
839 return get_with_( ptr.guard(), key, pred );
842 /// Clears the set (non-atomic)
844 The function unlink all items from the set.
845 The function is not atomic and not lock-free and should be used for debugging only.
852 /// Checks if the set is empty
854 Emptiness is checked by item counting: if item count is zero then assume that the set is empty.
855 Thus, the correct item counting feature is an important part of split-list set implementation.
859 return base_class::empty();
862 /// Returns item count in the set
865 return base_class::size();
870 using base_class::extract_;
871 using base_class::get_;
873 template <typename Q, typename Less>
874 bool extract_with_( typename gc::Guard& guard, Q const& key, Less pred )
876 return base_class::extract_with_( guard, key, typename maker::template predicate_wrapper<Less>::type() );
879 template <typename Q, typename Less>
880 bool get_with_( typename gc::Guard& guard, Q const& key, Less pred )
882 return base_class::get_with_( guard, key, typename maker::template predicate_wrapper<Less>::type() );
890 }} // namespace cds::container
892 #endif // #ifndef __CDS_CONTAINER_SPLIT_LIST_SET_H