...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
"boost/multi_index/sequenced_index_fwd.hpp"
synopsis"boost/multi_index/sequenced_index.hpp"
synopsis
"boost/multi_index/sequenced_index_fwd.hpp"
synopsisnamespace boost{ namespace multi_index{ // sequenced index specifier template<typename TagList=tag<> > struct sequenced; // indices namespace detail{ template<implementation defined> class index class name implementation defined; } // namespace boost::multi_index::detail } // namespace boost::multi_index } // namespace boost
sequenced_index_fwd.hpp
provides forward declarations for the
sequenced
index specifier and
its associated sequenced index class.
"boost/multi_index/sequenced_index.hpp"
synopsis#include <initializer_list> namespace boost{ namespace multi_index{ // sequenced index specifier template<typename TagList=tag<> > struct sequenced; // indices namespace detail{ template<implementation defined> class index class name implementation defined; // index comparison: // OP is any of ==,<,!=,>,>=,<= template<arg set 1,arg set 2> bool operator OP( const index class name<arg set 1>& x,const index class name<arg set 2>& y); // index specialized algorithms: template<implementation defined> void swap(index class name& x,index class name& y); } // namespace boost::multi_index::detail } // namespace boost::multi_index } // namespace boost
sequenced
index specifier
This index specifier allows for insertion of a sequenced index.
template<typename TagList=tag<> > struct sequenced;
If provided, TagList
must be an instantiation of
tag
.
Sequenced indices are modeled after the semantics of a bidirectional list
like std::list
. Elements in a sequenced index are by default
sorted according to their order of insertion: this means that new elements
inserted through a different index of the multi_index_container
are appended
to the end of the sequenced index. Additionally, the index allows for free
reordering of elements in the same vein as std::list
does.
Iterators (including to the end of the index) and pointers and references to an element
remain valid during the lifetime of the associated container (which can change
upon swapping), or until the referred-to element is erased or extracted;
pointers and references to an extracted element, but not so for iterators,
become valid again once the element is re-inserted.
Except where noted or if the corresponding interface does not exist, sequenced
indices verify the same container requirements as std::list
:
we only provide descriptions of those types and operations that are either not
present in std::list
or behave differently. Some of the
most important differences are:
std::list
.
std::list
, insertions into a sequenced index
may fail due to clashings with other indices. This alters the semantics
of the operations provided with respect to their analogues in
std::list
.
replace
and
modify
member functions.
namespace boost{ namespace multi_index{ namespace detail{ template<implementation defined: dependent on types Value, Allocator, TagList> class name is implementation defined { public: // types: typedef Value value_type; typedef boost::tuples::null_type ctor_args; typedef TagList tag_list; typedef Allocator allocator_type; typedef typename allocator_type::reference reference; typedef typename allocator_type::const_reference const_reference; typedef implementation defined iterator; typedef implementation defined const_iterator; typedef implementation defined size_type; typedef implementation defined difference_type; typedef typename allocator_type::pointer pointer; typedef typename allocator_type::const_pointer const_pointer; typedef equivalent to std::reverse_iterator<iterator> reverse_iterator; typedef equivalent to std::reverse_iterator<const_iterator> const_reverse_iterator; typedef same as owning container node_type; typedef following [container.insert.return] spec insert_return_type; // construct/copy/destroy: index class name& operator=(const index class name& x); index class name& operator=(std::initializer_list<value_type> list); template <class InputIterator> void assign(InputIterator first,InputIterator last); void assign(std::initializer_list<value_type> list); void assign(size_type n,const value_type& value); allocator_type get_allocator()const noexcept; // iterators: iterator begin()noexcept; const_iterator begin()const noexcept; iterator end()noexcept; const_iterator end()const noexcept; reverse_iterator rbegin()noexcept; const_reverse_iterator rbegin()const noexcept; reverse_iterator rend()noexcept; const_reverse_iterator rend()const noexcept; const_iterator cbegin()const noexcept; const_iterator cend()const noexcept; const_reverse_iterator crbegin()const noexcept; const_reverse_iterator crend()const noexcept; iterator iterator_to(const value_type& x); const_iterator iterator_to(const value_type& x)const; // capacity: bool empty()const noexcept; size_type size()const noexcept; size_type max_size()const noexcept; void resize(size_type n); void resize(size_type n,const value_type& x); // access: const_reference front()const; const_reference back()const; // modifiers: template<typename... Args> std::pair<iterator,bool> emplace_front(Args&&... args); std::pair<iterator,bool> push_front(const value_type& x); std::pair<iterator,bool> push_front(value_type&& x); void pop_front(); template<typename... Args> std::pair<iterator,bool> emplace_back(Args&&... args); std::pair<iterator,bool> push_back(const value_type& x); std::pair<iterator,bool> push_back(value_type&& x); void pop_back(); template<typename... Args> std::pair<iterator,bool> emplace(iterator position,Args&&... args); std::pair<iterator,bool> insert(iterator position,const value_type& x); std::pair<iterator,bool> insert(iterator position,value_type&& x); void insert(iterator position,size_type n,const value_type& x); template<typename InputIterator> void insert(iterator position,InputIterator first,InputIterator last); void insert(iterator position,std::initializer_list<value_type> list); insert_return_type insert(const_iterator position,node_type&& nh); node_type extract(const_iterator position); iterator erase(iterator position); iterator erase(iterator first,iterator last); bool replace(iterator position,const value_type& x); bool replace(iterator position,value_type&& x); template<typename Modifier> bool modify(iterator position,Modifier mod); template<typename Modifier,typename Rollback> bool modify(iterator position,Modifier mod,Rollback back); void swap(index class name& x); void clear()noexcept; // list operations: template<typename Index> void splice(const_iterator position,Index&& x); template<typename Index> std::pair<iterator,bool> splice( const_iterator position,Index&& x, typename std::remove_reference_t<Index>::const_iterator i); template<typename Index> void splice( const_iterator position,Index&& x, typename std::remove_reference_t<Index>::const_iterator first, typename std::remove_reference_t<Index>::const_iterator last); void remove(const value_type& value); template<typename Predicate> void remove_if(Predicate pred); void unique(); template <class BinaryPredicate> void unique(BinaryPredicate binary_pred); void merge(index class name& x); template <typename Compare> void merge(index class name& x,Compare comp); void sort(); template <typename Compare> void sort(Compare comp); void reverse()noexcept; // rearrange operations: void relocate(iterator position,iterator i); void relocate(iterator position,iterator first,iterator last); template<typename InputIterator> void rearrange(InputIterator first); } // index comparison: template<arg set 1,arg set 2> bool operator==( const index class name<arg set 1>& x, const index class name<arg set 2>& y) { return x.size()==y.size()&&std::equal(x.begin(),x.end(),y.begin()); } template<arg set 1,arg set 2> bool operator<( const index class name<arg set 1>& x, const index class name<arg set 2>& y) { return std::lexicographical_compare(x.begin(),x.end(),y.begin(),y.end()); } template<arg set 1,arg set 2> bool operator!=( const index class name<arg set 1>& x, const index class name<arg set 2>& y) { return !(x==y); } template<arg set 1,arg set 2> bool operator>( const index class name<arg set 1>& x ,const index class name<arg set 2>& y) { return y<x; } template<arg set 1,arg set 2> bool operator>=( const index class name<arg set 1>& x, const index class name<arg set 2>& y) { return !(x<y); } template<arg set 1,arg set 2> bool operator<=( const index class name<arg set 1>& x, const index class name<arg set 2>& y) { return !(x>y); } // index specialized algorithms: template<implementation defined> void swap(index class name& x,index class name& y); } // namespace boost::multi_index::detail } // namespace boost::multi_index } // namespace boost
Here and in the descriptions of operations of sequenced indices, we adopt the scheme outlined in the complexity signature section. The complexity signature of sequenced indices is:
c(n)=n*log(n)
,i(n)=1
(constant),h(n)=1
(constant),d(n)=1
(constant),r(n)=1
(constant),m(n)=1
(constant).Sequenced indices are instantiated internally to multi_index_container
and specified by means of
indexed_by
with the sequenced
index specifier. Instantiations are dependent on the following types:
Value
from multi_index_container
,Allocator
from multi_index_container
,TagList
from the index specifier (if provided, otherwise tag<>
is assumed).TagList
must be an instantiation of
tag
.
iterator
const_iterator
These types depend only onnode_type
and the position of the index in themulti_index_container
.
As explained in the index concepts section, indices do not have public constructors or destructors. Assignment, on the other hand, is provided.
index class name& operator=(const index class name& x);
Effects:wherea=b;a
andb
are themulti_index_container
objects to which*this
andx
belong, respectively.
Returns:*this
.
index class name& operator=(std::initializer_list<value_type> list);
Effects:wherea=list;a
is themulti_index_container
object to which*this
belongs.
Returns:*this
.
template <class InputIterator>
void assign(InputIterator first,InputIterator last);
Effects:clear(); insert(end(),first,last);
void assign(std::initializer_list<value_type> list);
Effects:assign(list.begin(),list.end());
void assign(size_type n,const value_type& value);
Effects:clear(); for(size_type i=0;i<n;++n)push_back(v);
iterator iterator_to(const value_type& x);
const_iterator iterator_to(const value_type& x)const;
Requires:x
is a reference to an element of the container.
Returns: An iterator tox
.
Complexity: Constant.
Exception safety:nothrow
.
void resize(size_type n);
void resize(size_type n,const value_type& x);
Requires (first version):value_type
isDefaultInsertable
intomulti_index_container
.
Requires (second version):value_type
isCopyInsertable
intomulti_index_container
.
Effects: Ifsize()<n
, tries to appendn-size()
default-inserted elements (first version) or copies ofx
(second version) at the end of the index. Ifn<size()
, erases the lastsize()-n
elements.
Note: If an expansion is requested, the size of the index is not guaranteed to ben
after this operation (other indices may ban insertions.)
template<typename... Args>
std::pair<iterator,bool> emplace_front(Args&&... args);
Effects:Returns: The return value is a pairemplace(begin(),std::forward<Args>(args)...);p
.p.second
istrue
if and only if insertion took place. On successful insertion,p.first
points to the element inserted; otherwise,p.first
points to an element that caused the insertion to be banned. Note that more than one element can be causing insertion not to be allowed.
std::pair<iterator,bool> push_front(const value_type& x);
std::pair<iterator,bool> push_front(value_type&& x);
Effects:Returns: The return value is a pairinsert(begin(),x); // lvalue ref version insert(begin(),std::move(x)); // rvalue ref versionp
.p.second
istrue
if and only if insertion took place. On successful insertion,p.first
points to the element inserted; otherwise,p.first
points to an element that caused the insertion to be banned. Note that more than one element can be causing insertion not to be allowed.
template<typename... Args>
std::pair<iterator,bool> emplace_back(Args&&... args);
Effects:Returns: The return value is a pairemplace(end(),std::forward<Args>(args)...);p
.p.second
istrue
if and only if insertion took place. On successful insertion,p.first
points to the element inserted; otherwise,p.first
points to an element that caused the insertion to be banned. Note that more than one element can be causing insertion not to be allowed.
std::pair<iterator,bool> push_back(const value_type& x);
std::pair<iterator,bool> push_back(value_type&& x);
Effects:Returns: The return value is a pairinsert(end(),x); // lvalue ref version insert(end(),std::move(x)); // rvalue ref versionp
.p.second
istrue
if and only if insertion took place. On successful insertion,p.first
points to the element inserted; otherwise,p.first
points to an element that caused the insertion to be banned. Note that more than one element can be causing insertion not to be allowed.
template<typename... Args>
std::pair<iterator,bool> emplace(iterator position,Args&&... args);
Requires:value_type
isEmplaceConstructible
intomulti_index_container
fromargs
.
Effects: Inserts avalue_type
object constructed withstd::forward<Args>(args)...
beforeposition
if insertion is allowed by all other indices of themulti_index_container
.
Returns: The return value is a pairp
.p.second
istrue
if and only if insertion took place. On successful insertion,p.first
points to the element inserted; otherwise,p.first
points to an element that caused the insertion to be banned. Note that more than one element can be causing insertion not to be allowed.
Complexity:O(I(n))
.
Exception safety: Strong.
std::pair<iterator,bool> insert(iterator position,const value_type& x);
std::pair<iterator,bool> insert(iterator position,value_type&& x);
Requires (first version):value_type
isCopyInsertable
intomulti_index_container
.position
is a valid iterator of the index.
Requires (second version):value_type
isMoveInsertable
intomulti_index_container
.position
is a valid iterator of the index.
Effects: Insertsx
beforeposition
if insertion is allowed by all other indices of themulti_index_container
.
Returns: The return value is a pairp
.p.second
istrue
if and only if insertion took place. On successful insertion,p.first
points to the element inserted; otherwise,p.first
points to an element that caused the insertion to be banned. Note that more than one element can be causing insertion not to be allowed.
Complexity:O(I(n))
.
Exception safety: Strong.
void insert(iterator position,size_type n,const value_type& x);
Effects:for(size_type i=0;i<n;++i)insert(position,x);
template<typename InputIterator>
void insert(iterator position,InputIterator first,InputIterator last);
Requires:position
is a valid iterator of the index.InputIterator
is an input iterator.value_type
isEmplaceConstructible
intomulti_index_container
from*first
.first
andlast
are not iterators into any index of themulti_index_container
to which this index belongs.last
is reachable fromfirst
.
Effects: For each element of [first
,last
), in this order, inserts it beforeposition
if insertion is allowed by all other indices of themulti_index_container
.
Complexity:O(m*I(n+m))
, wherem
is the number of elements in [first
,last
).
Exception safety: Basic.
void insert(iterator position,std::initializer_list<value_type> list);
Effects:insert(position,list.begin(),list.end());
insert_return_type insert(const_iterator position,node_type&& nh);
Requires:nh.empty() || get_allocator()==nh.get_allocator()
.
Effects: Does nothing ifnh
is empty; otherwise, inserts the node owned bynh
beforeposition
if insertion is allowed by all other indices of themulti_index_container
.
Postconditions:nh
is empty.
Returns: A valuep
of typeinsert_return_type
. Ifnh
is empty,p.position
isend()
,p.inserted
isfalse
andp.node
is empty; on successful insertion,p.position
points to the element inserted,p.inserted
istrue
andp.node
is empty; if the insertion failed,p.position
points to an element that caused the insertion to be banned,p.inserted
isfalse
andp.node
owns the original node. Note that more than one element can be causing insertion not to be allowed.
Complexity:O(I(n))
.
Exception safety: Strong. If an exception is thrown,nh
is not changed.
node_type extract(const_iterator position);
Requires:position
is a valid dereferenceable iterator of the index.
Effects: Extracts the node of the element pointed to byposition
.
Returns: A node handle owning the extracted node.
Complexity:O(D(n))
.
Exception safety:nothrow
.
iterator erase(iterator position);
Requires:position
is a valid dereferenceable iterator of the index.
Effects: Deletes the element pointed to byposition
.
Returns: An iterator pointing to the element immediately following the one that was deleted, orend()
if no such element exists.
Complexity:O(D(n))
.
Exception safety:nothrow
.
iterator erase(iterator first,iterator last);
Requires: [first
,last
) is a valid range of the index.
Effects: Deletes the elements in [first
,last
).
Returns:last
.
Complexity:O(m*D(n))
, wherem
is the number of elements in [first
,last
).
Exception safety:nothrow
.
bool replace(iterator position,const value_type& x);
bool replace(iterator position,value_type&& x);
Requires (first version):value_type
isCopyAssignable
.position
is a valid dereferenceable iterator of the index.
Requires (second version):value_type
isMoveAssignable
.position
is a valid dereferenceable iterator of the index.
Effects: Assigns the valuex
to the element pointed to byposition
into themulti_index_container
to which the index belongs if replacing is allowed by all other indices of themulti_index_container
.
Postconditions: Validity ofposition
is preserved in all cases.
Returns:true
if the replacement took place,false
otherwise.
Complexity:O(R(n))
.
Exception safety: Strong. If an exception is thrown by some user-provided operation themulti_index_container
to which the index belongs remains in its original state.
template<typename Modifier> bool modify(iterator position,Modifier mod);
Requires:mod
is a unary function object accepting arguments of typevalue_type&
.position
is a valid dereferenceable iterator of the index. The execution ofmod(e)
, wheree
is the element pointed to byposition
, does not invoke any operation of themulti_index_container
aftere
is directly modified or, before modification, if the operation would invalidateposition
.
Effects: Callsmod(e)
wheree
is the element pointed to byposition
and rearranges*position
into all the indices of themulti_index_container
. Rearrangement on sequenced indices does not change the position of the element with respect to the index; rearrangement on other indices may or might not succeed. If the rearrangement fails, the element is erased.
Postconditions: Validity ofposition
is preserved if the operation succeeds.
Returns:true
if the operation succeeded,false
otherwise.
Complexity:O(M(n))
.
Exception safety: Basic. If an exception is thrown by some user-provided operation (includingmod
), then the element pointed to byposition
is erased.
template<typename Modifier,typename Rollback>
bool modify(iterator position,Modifier mod,Rollback back);
Requires:mod
andback
are unary function objects accepting arguments of typevalue_type&
.position
is a valid dereferenceable iterator of the index. The execution ofmod(e)
, wheree
is the element pointed to byposition
, does not invoke any operation of themulti_index_container
aftere
is directly modified or, before modification, if the operation would invalidateposition
.back(e)
does not invoke any operation of themulti_index_container
.
Effects: Callsmod(e)
wheree
is the element pointed to byposition
and tries to rearrange*position
into all the indices of themulti_index_container
. Rearrangement on sequenced indices does not change the position of the element with respect to the index; rearrangement on other indices may or might not succeed. If the rearrangement fails,back(e)
is invoked: if the resulting value ofe
is consistent with its original position and constraints in all indices, the element is kept, otherwise it is erased.
Postconditions: Validity ofposition
is preserved except if the element is erased under the conditions described below.
Returns:true
if the operation succeeded,false
otherwise.
Complexity:O(M(n))
.
Exception safety: Strong, except ifmod
orback
throw an exception orback(e)
fails to properly restore the element or there is a throwing user-provided operation after invokingback(e)
, in which cases the modified element is erased. Ifback
throws inside the handling code executing after some other user-provided operation has thrown, it is the exception generated byback
that is rethrown.
Sequenced indices provide the full set of list operations found in
std::list
, extended in some cases such as splice
;
the semantics of these member functions, however,
typically differs from that of std::list
as insertions
may not succeed due to banning by other indices. Similarly, the complexity
of the operations may depend on the other indices belonging to the
same multi_index_container
.
template<typename Index> void splice(const_iterator position,Index&& x);
Requires:x
is a non-const reference to an index of a node-compatiblemulti_index_container
.position
is a valid iterator of the index, and must be exactlyend()
if the source and destination containers are the same.
Effects:splice(position,x,x.begin(),x.end());
template<typename Index> std::pair<iterator,bool> splice(
const_iterator position,Index&& x,
typename std::remove_reference_t<Index>::const_iterator i);
Requires:x
is a non-const reference to an index of a node-compatiblemulti_index_container
. Ifget_allocator()!=x.get_allocator()
,value_type
must beCopyInsertable
into the destinationmulti_index_container
.position
is a valid iterator of the index.i
is a valid dereferenceable iterator ofx
.
Effects:Postconditions: If transfer succeeds, for any index in the source container having the same
- (Same container) if the source and destination containers are the same, repositions the element pointed to by
i
beforeposition
unless both iterators refer to the same element.- (Transfer splice) else, if
get_allocator()==x.get_allocator()
, transfers the node of the element referred to byi
into the destinationmulti_index_container
right beforeposition
if insertion is allowed by all other indices of themulti_index_container
.- (Destructive splice) else, insertion of
*i
is tried beforeposition
; if the operation is successful, the element is erased fromx
.iterator
/const_iterator
types as the corresponding index in the destination container, iterators referring to*i
remain valid and behave as iterators of the destination index.
Returns: The return value is a pairp
.p.second
istrue
if and only if insertion (either through transfer or copy insertion) took place or the source and destination containers are the same. Ifp.second
istrue
,p.first
points to the inserted element or to*i
if the source and destination containers are the same; otherwise,p.first
points to an element that caused the insertion to be banned. Note that more than one element can be causing insertion not to be allowed.
Complexity: If the source and destination containers are the same, constant; otherwise,O(I(n)+D(x.size()))
.
Exception safety: If the source and destination containers are the same,nothrow
; otherwise strong.
Implementation note: The destructive variant of this operation is provided for reasons of backwards compatibility with previous versions of this library where allocator equality was not required.
template<typename Index> void splice(
const_iterator position,Index&& x,
typename std::remove_reference_t<Index>::const_iterator first,
typename std::remove_reference_t<Index>::const_iterator last);
Requires:x
is a non-const reference to an index of a node-compatiblemulti_index_container
. Ifget_allocator()!=x.get_allocator()
,value_type
must beCopyInsertable
into the destinationmulti_index_container
.position
is a valid iterator of the index and does not point to any element in [first
,last
). [first
,last
) is a valid range ofx
.
Effects:Postconditions: For any index in the source container having the same
- (Same container) if the source and destination containers are the same, repositions all the elements of [
first
,last
), in this order, beforeposition
.- (Transfer splice) else, if
get_allocator()==x.get_allocator()
, then, for each node in [first
,last
), in this order, the node is transferred to themulti_index_container
right beforeposition
if insertion is allowed by all other indices of themulti_index_container
.- (Destructive splice) else, for each element in [
first
,last
), in this order, insertion is tried beforeposition
; if the operation is successful, the element is erased fromx
.iterator
/const_iterator
types as the corresponding index in the destination container, iterators referring to the transferred elements remain valid and behave as iterators of the destination index.
Complexity: If&x==this
, constant; else, if the source and destination containers are the same,O(m)
; otherwise,O(m*(I(n+m)+D(x.size())))
, wherem
is the number of elements in [first
,last
).
Exception safety: If the source and destination containers are the same,nothrow
; otherwise basic.
Implementation note: The destructive variant of this operation is provided for reasons of backwards compatibility with previous versions of this library where allocator equality was not required.
void remove(const value_type& value);
Effects: Erases all elements of the index which compare equal tovalue
.
Complexity:O(n + m*D(n))
, wherem
is the number of elements erased.
Exception safety: Basic.
template<typename Predicate> void remove_if(Predicate pred);
Effects: Erases all elementsx
of the index for whichpred(x)
holds.
Complexity:O(n + m*D(n))
, wherem
is the number of elements erased.
Exception safety: Basic.
void unique();
Effects: Eliminates all but the first element from every consecutive group of equal elements referred to by the iteratori
in the range [first+1
,last
) for which*i==*(i-1)
.
Complexity:O(n + m*D(n))
, wherem
is the number of elements erased.
Exception safety: Basic.
template <class BinaryPredicate> void unique(BinaryPredicate binary_pred);
Effects: Eliminates all but the first element from every consecutive group of elements referred to by the iteratori
in the range [first+1
,last
) for whichbinary_pred(*i,*(i-1))
holds.
Complexity:O(n + m*D(n))
, wherem
is the number of elements erased.
Exception safety: Basic.
void merge(index class name& x);
Requires: Eitherget_allocator()==x.get_allocator()
orvalue_type
isCopyInsertable
into themulti_index_container
.std::less<value_type>
induces a strict weak ordering overvalue_type
. Both the index andx
are sorted according tostd::less<value_type>
.
Effects: Attempts to splice every element ofx
into the corresponding position of the index (according to the order). The resulting sequence is stable, i.e. equivalent elements of either container preserve their relative position. In the special case&x==this
, no operation is performed.
Postconditions: Elements in the index and remaining elements inx
are sorted. Validity of iterators and references is preserved, except to elements removed fromx
ifget_allocator()!=x.get_allocator()
.
Complexity: If&x==this
, constant; otherwiseO(n + x.size()*I(n+x.size()) + x.size()*D(x.size()))
.
Exception safety: If&x==this
,nothrow
; otherwise, basic.
template <typename Compare> void merge(index class name& x,Compare comp);
Requires: Eitherget_allocator()==x.get_allocator()
orvalue_type
isCopyInsertable
into themulti_index_container
.Compare
induces a strict weak ordering overvalue_type
. Both the index andx
are sorted according tocomp
.
Effects: Attempts to splice every element ofx
into the corresponding position of the index (according tocomp
). The resulting sequence is stable, i.e. equivalent elements of either container preserve their relative position. In the special case&x==this
, no operation is performed.
Postconditions: Elements in the index and remaining elements inx
are sorted according tocomp
. Validity of iterators and references is preserved, except to elements removed fromx
ifget_allocator()!=x.get_allocator()
.
Complexity: If&x==this
, constant; otherwiseO(n + x.size()*I(n+x.size()) + x.size()*D(x.size()))
.
Exception safety: If&x==this
,nothrow
; otherwise, basic.
void sort();
Requires:std::less<value_type>
induces a strict weark ordering overvalue_type
.
Effects: Sorts the index according tostd::less<value_type>
. The sorting is stable, i.e. equivalent elements preserve their relative position.
Postconditions: Validity of iterators and references is preserved.
Complexity:O(n*log(n))
.
Exception safety:nothrow
ifstd::less<value_type>
does not throw; otherwise, basic.
template <typename Compare> void sort(Compare comp);
Requires:Compare
induces a strict weak ordering overvalue_type
.
Effects: Sorts the index according tocomp
. The sorting is stable, i.e. equivalent elements preserve their relative position.
Postconditions: Validity of iterators and references is preserved.
Complexity:O(n*log(n))
.
Exception safety:nothrow
ifcomp
does not throw; otherwise, basic.
void reverse()noexcept;
Effects: Reverses the order of the elements in the index.
Postconditions: Validity of iterators and references is preserved.
Complexity:O(n)
.
These operations, without counterpart in std::list
(although splice
provides partially overlapping
functionality), perform individual and global repositioning of elements
inside the index.
void relocate(iterator position,iterator i);
Requires:position
is a valid iterator of the index.i
is a valid dereferenceable iterator of the index.
Effects: Inserts the element pointed to byi
beforeposition
. Ifposition==i
, no operation is performed.
Postconditions: No iterator or reference is invalidated.
Complexity: Constant.
Exception safety:nothrow
.
void relocate(iterator position,iterator first,iterator last);
Requires:position
is a valid iterator of the index.first
andlast
are valid iterators of the index.last
is reachable fromfirst
.position
is not in the range [first
,last
).
Effects: The range of elements [first
,last
) is repositioned just beforeposition
.
Postconditions: No iterator or reference is invalidated.
Complexity: Constant.
Exception safety:nothrow
.
template<typename InputIterator> void rearrange(InputIterator first);
Requires: The range [first
,std::advance(first,n)
), wheren
is the size of the index, is a free view of the index.
Effects: The elements are rearranged so as to match the order of the previously described view.
Postconditions: No iterator or reference is invalidated.
Complexity:O(n)
.
Exception safety: Basic.
Indices cannot be serialized on their own, but only as part of the
multi_index_container
into which they are embedded. In describing
the additional preconditions and guarantees associated to sequenced indices
with respect to serialization of their embedding containers, we
use the concepts defined in the multi_index_container
serialization section.
multi_index_container
m
to an
output archive (XML archive) ar
.
Requires: No additional requirements to those imposed by the container.Operation: loading of a
multi_index_container
m'
from an
input archive (XML archive) ar
.
Requires: No additional requirements to those imposed by the container.Operation: saving of an
Postconditions: On successful loading, each of the elements of [begin()
,end()
) is a restored copy of the corresponding element in [m.get<i>().begin()
,m.get<i>().end()
), wherei
is the position of the sequenced index in the container.
iterator
or const_iterator
it
to an output archive (XML archive) ar
.
Requires:Operation: loading of anit
is a valid iterator of the index. The associatedmulti_index_container
has been previously saved.
iterator
or const_iterator
it'
from an input archive (XML archive) ar
.
Postconditions: On successful loading, ifit
was dereferenceable then*it'
is the restored copy of*it
, otherwiseit'==end()
.
Note: It is allowed thatit
be aconst_iterator
and the restoredit'
aniterator
, or viceversa.
Revised August 30th 2021
© Copyright 2003-2021 Joaquín M López Muñoz. Distributed under 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)