Namespace
Varianti

std::weak_ptr::weak_ptr

Da cppreference.com.
< cpp‎ | memory‎ | weak ptr

 
 
Utilità libreria
Tipo di supporto (basic types, RTTI, type traits)
Gestione della memoria dinamica
La gestione degli errori
Programma di utilità
Funzioni variadic
Data e ora
Funzione oggetti
initializer_list(C++11)
bitset
hash(C++11)
Gli operatori relazionali
Original:
Relational operators
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
rel_ops::operator!=
rel_ops::operator>
rel_ops::operator<=
rel_ops::operator>=
Coppie e tuple
Original:
Pairs and tuples
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
pair
tuple(C++11)
piecewise_construct_t(C++11)
piecewise_construct(C++11)
Swap, in avanti e spostare
Original:
Swap, forward and move
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
swap
forward(C++11)
move(C++11)
move_if_noexcept(C++11)
declval(C++11)
 
Gestione della memoria dinamica
Basso livello di gestione della memoria
Allocatori
Original:
Allocators
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
allocator
allocator_traits(C++11)
allocator_arg_t(C++11)
allocator_arg(C++11)
uses_allocator(C++11)
scoped_allocator_adaptor(C++11)
Non inizializzata stoccaggio
Original:
Uninitialized storage
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
uninitialized_copy
uninitialized_copy_n(C++11)
uninitialized_fill
uninitialized_fill_n
raw_storage_iterator
get_temporary_buffer
return_temporary_buffer
Puntatori intelligenti
Original:
Smart pointers
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
unique_ptr(C++11)
shared_ptr(C++11)
weak_ptr(C++11)
auto_ptr(deprecato)
owner_less(C++11)
enable_shared_from_this(C++11)
bad_weak_ptr(C++11)
default_delete(C++11)
Garbage collection supporto
Original:
Garbage collection support
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
declare_reachable(C++11)
undeclare_reachable(C++11)
declare_no_pointers(C++11)
undeclare_no_pointers(C++11)
pointer_safety(C++11)
get_pointer_safety(C++11)
Varie
Original:
Miscellaneous
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
pointer_traits(C++11)
addressof(C++11)
align(C++11)
C Library
Original:
C Library
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
 
std::weak_ptr
Membri funzioni
Original:
Member functions
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
weak_ptr::weak_ptr
weak_ptr::~weak_ptr
weak_ptr::operator=
Modificatori
Original:
Modifiers
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
weak_ptr::reset
weak_ptr::swap
Osservatori
Original:
Observers
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
weak_ptr::use_count
weak_ptr::expired
weak_ptr::lock
weak_ptr::owner_before
Non membri funzioni
Original:
Non-member functions
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
std::swap
 
constexpr weak_ptr();
(1) (dal C++11)
weak_ptr( const weak_ptr& r );
(2) (dal C++11)
template< class Y >
weak_ptr( const weak_ptr<Y>& r );
(2) (dal C++11)
template< class Y >
weak_ptr( const std::shared_ptr<Y>& r );
(2) (dal C++11)
Costruisce weak_ptr nuova che condivide potenzialmente un oggetto con r.
Original:
Constructs new weak_ptr that potentially shares an object with r.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
1)
Costruttore di default. Costruisce weak_ptr vuoto.
Original:
Default constructor. Constructs empty weak_ptr.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
2)
Costruisce weak_ptr nuova che condivide un oggetto gestito da r. Se r gestisce nessun oggetto, *this gestisce nessun oggetto troppo. Gli overload basate su modelli non prende parte alla risoluzione di sovraccarico a meno Y* la conversione implicita in T*.
Original:
Constructs new weak_ptr which shares an object managed by r. If r manages no object, *this manages no object too. The templated overloads don't participate in the overload resolution unless Y* is implicitly convertible to T*.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

Indice

[modifica] Parametri

r -
un std::shared_ptr o std::weak_ptr che verrà visualizzato da questo std::weak_ptr
Original:
a std::shared_ptr or std::weak_ptr that will be viewed by this std::weak_ptr
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

[modifica] Eccezioni

noexcept specification:  
noexcept
  (dal C++11)

[modifica] Esempio

#include <memory>
#include <iostream>
 
struct Foo {};
 
int main()
{
   std::weak_ptr<Foo> w_ptr;
 
   {
      auto ptr = std::make_shared<Foo>();
      w_ptr = ptr;
      std::cout << "w_ptr.use_count() inside scope: " << w_ptr.use_count() << '\n';
   }
 
   std::cout << "w_ptr.use_count() out of scope: " << w_ptr.use_count() << '\n';
}

Output:

w_ptr.use_count() inside scope: 1
w_ptr.use_count() out of scope: 0

[modifica] Vedi anche

assegna il weak_ptr
Original:
assigns the weak_ptr
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

(membro pubblico funzione) [edit]