deduction guides for std::pair

 

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pair tuple (C++11) apply (C++17) make_from_tuple (C++17)	optional (C++17) any (C++17) variant (C++17)
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std::pair

Member functions

pair::pair

pair::operator=

pair::swap

Non-member functions

make_pair

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

std::swap

get (C++11)

Deduction guides(C++17)

Helper classes

tuple_size (C++11)

tuple_element (C++11)

 

Defined in header <utility>
template<class T1, class T2> pair(T1, T2) -> pair<T1, T2>;		(since C++17)

One deduction guide is provided for std::pair to account for the edge cases missed by the implicit deduction guides.

In particular, non-copyable arguments and array to pointer conversion

Example

Run this code

#include <utility>
 
int main()
{
    int a[2], b[3];
    std::pair p{a, b}; // explicit deduction guide is used in this case
}