std::tuple_size<std::tuple>

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C++

Linguaggio

Concetti

Libreria di Utilità

Stringhe

Contenitori

Algoritmi

Iteratori

Libreria matematca

Input/output

Localizzazione

Espressioni regolari (C++11)

Operazioni atomicche (C++11)

Multithreading (C++11)

 

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)

 

std::tuple

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.

tuple::tuple

tuple::operator=

tuple::swap

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.

make_tuple

tie

forward_as_tuple

None

operator= operator!= operator< operator<= operator> operator>=

std::swap

get

Helper classi Original: Helper classes The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

tuple_size

tuple_element

uses_allocator

ignore

 

<tbody> </tbody>

Elemento definito nell'header <tuple>
template< class T > class tuple_size; /*undefined*/	(1)	(dal C++11)
template< class... Types > class tuple_size<tuple<Types...> > : public std::integral_constant<std::size_t, sizeof...(Types)> { };	(2)	(dal C++11)
template< class T > class tuple_size<const T> : public std::integral_constant< typename std::remove_cv<decltype(std::tuple_size<T>::value)>::type, std::tuple_size<Tp>::value> { };	(3)	(dal C++11)
template< class T > class tuple_size< volatile T > : public std::integral_constant< typename std::remove_cv<decltype(std::tuple_size<T>::value)>::type, std::tuple_size<Tp>::value> { };	(4)	(dal C++11)
template< class T > class tuple_size< const volatile T > : public std::integral_constant< typename std::remove_cv<decltype(std::tuple_size<T>::value)>::type, std::tuple_size<Tp>::value> { };	(5)	(dal C++11)

Consente di accedere al numero di elementi in una tupla come un tempo di compilazione espressione costante.

Original:

Provides access to the number of elements in a tuple as a compile-time constant expression.

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

Inherited from std::integral_constant

Member constants

value [statico]	sizeof...(Types) (pubblico membro statico costante)

Member functions

operator std::size_t	converte l'oggetto in std::size_t, restituisce value Original: converts the object to std::size_t, returns value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (metodo pubblico)

Member types

Tipo Original: Type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.	Definition
value_type	std::size_t
type	std::integral_constant<std::size_t, value>

Esempio

#include <iostream>
#include <tuple>

template<class T>
void test(T t)
{
    int a[std::tuple_size<T>::value]; // can be used at compile time
    std::cout << std::tuple_size<T>::value << '\n'; // or at run time
}

int main()
{
    test(std::make_tuple(1, 2, 3.14));
}

Output:

3

Vedi anche

std::tuple_size<std::array>	ottiene la dimensione di un array Original: obtains the size of an array The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (classe modello di specializzazione)
std::tuple_size<std::pair> (C++11)	ottiene la dimensione di un pair Original: obtains the size of a pair The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (classe modello di specializzazione)
std::get(std::tuple)	tupla accede elemento specificato Original: tuple accesses specified element The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (funzione di modello)
tuple_element	ottiene il tipo dell'elemento specificato Original: obtains the type of the specified element The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (classe modello di specializzazione)