<deque>
namespace std { template<class T, class A> class deque; // TEMPLATE FUNCTIONS template<class T, class A> bool operator==( const deque<T, A>& lhs, const deque<T, A>& rhs); template<class T, class A> bool operator!=( const deque<T, A>& lhs, const deque<T, A>& rhs); template<class T, class A> bool operator<( const deque<T, A>& lhs, const deque<T, A>& rhs); template<class T, class A> bool operator>( const deque<T, A>& lhs, const deque<T, A>& rhs); template<class T, class A> bool operator<=( const deque<T, A>& lhs, const deque<T, A>& rhs); template<class T, class A> bool operator>=( const deque<T, A>& lhs, const deque<T, A>& rhs); template<class T, class A> void swap( const deque<T, A>& lhs, const deque<T, A>& rhs); };
Include the STL
standard header <deque>
to define the
container
template class deque
and three supporting
templates.
deque
allocator_type
· assign
· at
· back
· begin
· clear
· const_iterator
· const_reference
· const_reverse_iterator
· deque
· difference_type
· empty
· end
· erase
· front
· get_allocator
· insert
· iterator
· max_size
· operator[]
· pop_back
· pop_front
· push_back
· push_front
· rbegin
· reference
· rend
· resize
· reverse_iterator
· size
· size_type
· swap
· value_type
template<class T, class A = allocator<T> > class deque { public: typedef A allocator_type; typedef typename A::size_type size_type; typedef typename A::difference_type difference_type; typedef typename A::reference reference; typedef typename A::const_reference const_reference; typedef typename A::value_type value_type; typedef T0 iterator; typedef T1 const_iterator; typedef reverse_iterator<const_iterator> const_reverse_iterator; typedef reverse_iterator<iterator> reverse_iterator; deque(); explicit deque(const A& al); explicit deque(size_type n); deque(size_type n, const T& v); deque(size_type n, const T& v, const A& al); deque(const deque& x); template<class InIt> deque(InIt first, InIt last); template<class InIt> deque(InIt first, InIt last, const A& al); iterator begin(); const_iterator begin() const; iterator end(); iterator end() const; reverse_iterator rbegin(); const_reverse_iterator rbegin() const; reverse_iterator rend(); const_reverse_iterator rend() const; void resize(size_type n); void resize(size_type n, T x); size_type size() const; size_type max_size() const; bool empty() const; A get_allocator() const; reference at(size_type pos); const_reference at(size_type pos) const; reference operator[](size_type pos); const_reference operator[](size_type pos); reference front(); const_reference front() const; reference back(); const_reference back() const; void push_front(const T& x); void pop_front(); void push_back(const T& x); void pop_back(); template<class InIt> void assign(InIt first, InIt last); void assign(size_type n); void assign(size_type n, const T& x); iterator insert(iterator it); iterator insert(iterator it, const T& x); void insert(iterator it, size_type n, const T& x); template<class InIt> void insert(iterator it, InIt first, InIt last); iterator erase(iterator it); iterator erase(iterator first, iterator last); void clear(); void swap(deque x); protected: A allocator; };
The template class describes an object that controls a
varying-length sequence of elements of type T
.
The sequence is represented in a way that permits insertion
and removal of an element at either end with a single element copy
(constant time).
Such operations in the middle of the sequence require element
copies and assignments proportional to the number of elements
in the sequence (linear time).
The object allocates and frees storage for the sequence it controls
through a protected object named
allocator
,
of class A
. Such an
allocator object must have
the same external interface as an object of template class
allocator
.
Note that allocator
is not copied when the
object is assigned.
Deque reallocation occurs when a member function must insert or erase elements of the controlled sequence:
begin()
and
end()
become
invalid.first()
,
then all iterators but no references,
that designate existing elements become invalid.end()
,
then end()
and all iterators,
but no references, that designate existing elements become
invalid.first()
,
only that iterator and references to the erased element
become invalid.last() - 1
,
only that iterator, last()
, and
references to the erased element become invalid.deque::allocator_type
typedef A allocator_type;
The type is a synonym for the template parameter A
.
deque::assign
template<class InIt> void assign(InIt first, InIt last); void assign(size_type n); void assign(size_type n, const T& x);
If InIt
is an integer type, the first member
function behaves the same as assign((size_type)first, (T)last)
.
Otherwise, the
first member function replaces the sequence
controlled by *this
with the sequence
[first, last)
, which must not overlap
the initial controlled sequence.
The second member function replaces the sequence
controlled by *this
with a repetition of n
elements of value
T()
.
The third member function replaces the sequence
controlled by *this
with a repetition of n
elements of value x
.
deque::at
const_reference at(size_type pos) const; reference at(size_type pos);
The member function returns a reference to the element of the
controlled sequence at position pos
. If that position is
invalid, the function throws an object of class
out_of_range
.
deque::back
reference back(); const_reference back() const;
The member function returns a reference to the last element of the controlled sequence, which must be non-empty.
deque::begin
const_iterator begin() const; iterator begin();
The member function returns a random-access iterator that points at the first element of the sequence (or just beyond the end of an empty sequence).
deque::clear
void clear();
The member function calls
erase(
begin(),
end())
.
deque::const_iterator
typedef T1 const_iterator;
The type describes an object that can serve as a constant
random-access iterator for the controlled sequence.
It is described here as a
synonym for the unspecified type T1
.
deque::const_reference
typedef typename A::const_reference const_reference;
The type describes an object that can serve as a constant reference to an element of the controlled sequence.
deque::const_reverse_iterator
typedef reverse_iterator<const_iterator> const_reverse_iterator;
The type describes an object that can serve as a constant reverse random-access iterator for the controlled sequence.
deque::deque
deque(); explicit deque(const A& al); explicit deque(size_type n); deque(size_type n, const T& v); deque(size_type n, const T& v, const A& al); deque(const deque& x); template<class InIt> deque(InIt first, InIt last); template<class InIt> deque(InIt first, InIt last, const A& al);
All constructors store an
allocator object in
allocator
and
initialize the controlled sequence. The allocator object is the argument
al
, if present. For the copy constructor, it is
x.get_allocator()
.
Otherwise, it is A()
.
The first two constructors specify an
empty initial controlled sequence. The third constructor specifies
a repetition of n
elements of value T()
.
The fourth and fifth constructors specify
a repetition of n
elements of value x
.
The sixth constructor specifies a copy of the sequence controlled by
x
.
If InIt
is an integer type, the last two constructors
specify a repetition of (size_type)first
elements of value
(T)last
. Otherwise, the
last two constructors specify the sequence
[first, last)
.
deque::difference_type
typedef typename A::difference_type difference_type;
The signed integer type describes an object that can represent the difference between the addresses of any two elements in the controlled sequence.
deque::empty
bool empty() const;
The member function returns true for an empty controlled sequence.
deque::end
const_iterator end() const; iterator end();
The member function returns a random-access iterator that points just beyond the end of the sequence.
deque::erase
iterator erase(iterator it); iterator erase(iterator first, iterator last);
The first member function removes the element of the controlled
sequence pointed to by it
. The second member function
removes the elements of the controlled sequence
in the range [first, last)
.
Both return an iterator that designates the first element remaining
beyond any elements removed, or
end()
if no such element exists.
Removing N
elements causes N
destructor calls
and an assignment for each of the elements between the insertion
point and the nearer end of the sequence.
Removing an element at either end
invalidates only iterators and
references that designate the erased elements. Otherwise,
erasing an element invalidates all iterators and references.
deque::front
reference front(); const_reference front() const;
The member function returns a reference to the first element of the controlled sequence, which must be non-empty.
deque::get_allocator
A get_allocator() const;
The member function returns
allocator
.
deque::insert
iterator insert(iterator it); iterator insert(iterator it, const T& x); void insert(iterator it, size_type n, const T& x); template<class InIt> void insert(iterator it, InIt first, InIt last);
Each of the member functions inserts, before the element pointed to
by it
in the controlled sequence, a sequence
specified by the remaining operands.
The first member function inserts
a single element with value T()
and returns an iterator
that points to the newly inserted element.
The second member function inserts
a single element with value x
and returns an iterator
that points to the newly inserted element.
The third member function
inserts a repetition of n
elements of value x
.
If InIt
is an integer type, the last member
function behaves the same as insert(it, (size_type)first, (T)last)
.
Otherwise, the
last member function inserts the sequence
[first, last)
, which must not overlap
the initial controlled sequence.
When inserting a single element, the number of
element copies is linear in the number of elements between the insertion
point and the nearer end of the sequence. When inserting a single element
at either end of the sequence, the amortized number of element copies
is constant. When inserting N
elements,
the number of element copies is linear in
N
plus the number of elements between the insertion
point and the nearer end of the sequence -- except when the template member
is specialized for InIt
an input or forward iterator, which
behaves like N
single insertions.
Inserting an element at either end
invalidates all iterators,
but no references, that designate existing elements. Otherwise,
inserting an element invalidates all iterators and references.
deque::iterator
typedef T0 iterator;
The type describes an object that can serve as a random-access
iterator for the controlled sequence.
It is described here as a
synonym for the unspecified type T0
.
deque::max_size
size_type max_size() const;
The member function returns the length of the longest sequence that the object can control.
deque::operator[]
const_reference operator[](size_type pos) const; reference operator[](size_type pos);
The member function returns a reference to the element of the
controlled sequence at position pos
. If that position is
invalid, the behavior is undefined.
deque::pop_back
void pop_back();
The member function removes the last element of the controlled sequence, which must be non-empty. Removing the element invalidates only iterators and references that designate the erased element.
deque::push_back
void push_back(const T& x);
The member function inserts an element with value x
at the end of the controlled sequence. Inserting the element
invalidates all iterators,
but no references, to existing elements.
deque::pop_front
void pop_front();
The member function removes the first element of the controlled sequence, which must be non-empty. Removing the element invalidates only iterators and references that designate the erased element.
deque::push_front
void push_front(const T& x);
The member function inserts an element with value x
at the beginning of the controlled sequence. Inserting the element
invalidates all iterators,
but no references, to existing elements.
deque::rbegin
const_reverse_iterator rbegin() const; reverse_iterator rbegin();
The member function returns a reverse iterator that points just beyond the end of the controlled sequence. Hence, it designates the beginning of the reverse sequence.
deque::reference
typedef typename A::reference reference;
The type describes an object that can serve as a reference to an element of the controlled sequence.
deque::rend
const_reverse_iterator rend() const; reverse_iterator rend();
The member function returns a reverse iterator that points at the first element of the sequence (or just beyond the end of an empty sequence). Hence, it designates the end of the reverse sequence.
deque::resize
void resize(size_type n); void resize(size_type n, T x);
The member functions both ensure that
size()
henceforth
returns n
. If it must make the controlled sequence longer,
the first member function
appends elements with value T()
, while the second member function
appends elements with value x
.
To make the controlled sequence shorter, both member functions call
erase(begin() + n, end())
.
deque::reverse_iterator
typedef reverse_iterator<iterator> reverse_iterator;
The type describes an object that can serve as a reverse random-access iterator for the controlled sequence.
deque::size
size_type size() const;
The member function returns the length of the controlled sequence.
deque::size_type
typedef typename A::size_type size_type;
The unsigned integer type describes an object that can represent the length of any controlled sequence.
deque::swap
void swap(deque& str);
The member function swaps the controlled sequences between
*this
and str
. If
allocator
== str.allocator
, it does so in constant time;
and it throws no exceptions. Otherwise,
it performs a number of element assignments and constructor calls
proportional to the number of elements in the two controlled sequences.
deque::value_type
typedef typename A::value_type value_type;
The type is a synonym for the template parameter T
.
operator!=
template<class T, class A> bool operator!=( const deque <T, A>& lhs, const deque <T, A>& rhs);
The template function returns !(lhs == rhs)
.
operator==
template<class T, class A> bool operator==( const deque <T, A>& lhs, const deque <T, A>& rhs);
The template function overloads operator==
to compare
two objects of template class
deque
. The function returns
lhs.size() == rhs.size() &&
equal(lhs.
begin(), lhs.
end(), rhs.begin())
.
operator<
template<class T, class A> bool operator<( const deque <T, A>& lhs, const deque <T, A>& rhs);
The template function overloads operator<
to compare
two objects of template class
deque
. The function returns
lexicographical_compare(lhs.
begin(), lhs.
end(), rhs.begin(), rhs.end())
.
operator<=
template<class T, class A> bool operator<=( const deque <T, A>& lhs, const deque <T, A>& rhs);
The template function returns !(rhs < lhs)
.
operator>
template<class T, class A> bool operator>( const deque <T, A>& lhs, const deque <T, A>& rhs);
The template function returns rhs < lhs
.
operator>=
template<class T, class A> bool operator>=( const deque <T, A>& lhs, const deque <T, A>& rhs);
The template function returns !(rhs < lhs)
.
swap
template<class T, class A> void swap( const deque <T, A>& lhs, const deque <T, A>& rhs);
The template function executes
lhs.swap(rhs)
.
See also the Table of Contents and the Index.
Copyright © 1992-1996 by P.J. Plauger. Portions derived from work copyright © 1994 by Hewlett-Packard Company. All rights reserved.