Espaços nominais
Variantes
Acções

std::weak_ptr::owner_before

Da cppreference.com
< cpp‎ | memory‎ | weak ptr

 
 
Biblioteca de utilitários
Digite apoio (basic types, RTTI, type traits)
Gerenciamento de memória dinâmica
De tratamento de erros
Utilidades do programa
Variadic funções
Data e hora
Objetos de função
initializer_list(C++11)
bitset
hash(C++11)
Os operadores relacionais
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>=
Pares e tuplas
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)
Troque, avançar e avançar
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)
 
Gerenciamento de memória dinâmica
Gerenciamento de memória de baixo nível
Alocadores
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)
Uninitialized armazenamento
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
Ponteiros inteligentes
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(obsoleta)
owner_less(C++11)
enable_shared_from_this(C++11)
bad_weak_ptr(C++11)
default_delete(C++11)
Apoio a coleta de lixo
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)
Diversos
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
Funções de membro
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=
Modificadores
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
Observadores
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
Não-membros funções
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
 
template< class T >
bool owner_before( const weak_ptr<T>& other) const;
template< class T >
bool owner_before( const std::shared_ptr<T>& other) const;
Verifica se esta weak_ptr precede other na aplicação definida proprietário baseado (em oposição ao valor) ordem. A ordem é tal que dois ponteiros inteligentes comparar equivalente só se forem ambos vazios ou se ambos do próprio objeto, mesmo se os valores dos indicadores obtidos pelo get () são diferentes (por exemplo, porque eles apontam subobjetos diferentes dentro do mesmo objeto)
Original:
Checks whether this weak_ptr precedes other in implementation defined owner-based (as opposed to value-based) order. The order is such that two smart pointers compare equivalent only if they are both empty or if they both own the same object, even if the values of the pointers obtained by get() are different (e.g. because they point at different subobjects within the same object)
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
Esta ordenação é usado para fazer partilhada e ponteiros fracos utilizável como chaves em recipientes associativos, tipicamente através std::owner_less.
Original:
This ordering is used to make shared and weak pointers usable as keys in associative containers, typically through std::owner_less.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

Índice

[editar] Parâmetros

other -
o std::shared_ptr ou std::weak_ptr a ser comparada
Original:
the std::shared_ptr or std::weak_ptr to be compared
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

[editar] Valor de retorno

true se *this precede other, false contrário. Implementações comuns comparar os endereços dos blocos de controle.
Original:
true if *this precedes other, false otherwise. Common implementations compare the addresses of the control blocks.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

[editar] Exemplo

#include <iostream>
#include <memory>
 
struct Foo {
    int n1;
    int n2; 
    Foo(int a, int b) : n1(a), n2(b) {}
};
int main()
{   
    auto p1 = std::make_shared<Foo>(1, 2);
    std::shared_ptr<int> p2(p1, &p1->n1);
    std::shared_ptr<int> p3(p1, &p1->n2);
 
    std::cout << std::boolalpha
              << "p2 < p3 " << (p2 < p3) << '\n'
              << "p3 < p2 " << (p3 < p2) << '\n'
              << "p2.owner_before(p3) " << p2.owner_before(p3) << '\n'
              << "p3.owner_before(p2) " << p3.owner_before(p2) << '\n';
 
    std::weak_ptr<int> w2(p2);
    std::weak_ptr<int> w3(p3);
    std::cout 
//              << "w2 < w3 " << (w2 < w3) << '\n'  // won't compile 
//              << "w3 < w2 " << (w3 < w2) << '\n'  // won't compile
              << "w2.owner_before(w3) " << w2.owner_before(w3) << '\n'
              << "w3.owner_before(w2) " << w3.owner_before(w2) << '\n';
 
}

Output:

p2 < p3 true
p3 < p2 false
p2.owner_before(p3) false
p3.owner_before(p2) false
w2.owner_before(w3) false
w3.owner_before(w2) false

[editar] Veja também

fornece de tipo misto ordenação proprietário baseado de ponteiros compartilhados e fraco
Original:
provides mixed-type owner-based ordering of shared and weak pointers
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

(modelo de classe) [edit]