std::make_pair

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C++

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initializer_list (C++11)

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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)

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declval (C++11)

 

std::pair

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.

pair::pair

pair::operator=

pair::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_pair

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

std::swap

get (C++11)

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 (C++11)

tuple_element (C++11)

 

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Elemento definito nell'header <utility>
template< class T1, class T2 > std::pair<T1,T2> make_pair( T1 t, T2 u ); template< class T1, class T2 > std::pair<V1,V2> make_pair( T1&& t, T2&& u );		(fino al c++11) (dal C++11)

Crea un oggetto std::pair, dedurre il tipo di destinazione dai tipi di argomenti.

Original:

Creates a std::pair object, deducing the target type from the types of arguments.

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I tipi sono dedotte std::decay<T1>::type e std::decay<T2>::type (le trasformazioni di tipo applicando i consueti argomenti di funzioni passati per valore) salvo applicazione di risultati std::decay in std::reference_wrapper<X> per qualche tipo X, nel qual caso il tipo viene dedotto è X&. (dal C++11)

Original:

The deduced types are std::decay<T1>::type and std::decay<T2>::type (the usual type transformations applied to arguments of functions passed by value) unless application of std::decay results in std::reference_wrapper<X> for some type X, in which case the deduced type is is X&. (dal C++11)

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Parametri

t, u

-

i valori di costruire la coppia da Original: the values to construct the pair from The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Valore di ritorno

un oggetto std::pair contenente i valori indicati.

Original:

an std::pair object containing the given values.

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Esempio

#include <iostream>
#include <utility>
#include <functional>

int main()
{
    int n = 1;
    int a[5] = {1,2,3,4,5};

    // build a pair from two ints
    auto p1 = std::make_pair(n, a[1]);
    std::cout << "The value of p1 is "
              << "(" << p1.first << ", " << p1.second << ")\n";

    // build a pair from a reference to int and an array (decayed to pointer)
    auto p2 = std::make_pair(std::ref(n), a);
    n = 7;
    std::cout << "The value of p2 is "
              << "(" << p2.first << ", " << *(p2.second+1) << ")\n";
}

Output:

The value of p1 is (1, 2)
The value of p2 is (7, 2)