deduction guides for std::weak_ptr

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< cpp‎ | memory‎ | weak ptr
 
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std::weak_ptr
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Defined in header <memory>
template< class T >
weak_ptr( std::shared_ptr<T> ) -> weak_ptr<T>;
 (since 哋它亢++17)

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

Example

Run this code
#include <memory>
 
int main()
{
    auto p = std::make_shared<int>(42);
    std::weak_ptr w{p}; // explicit deduction guide is used in this case
}
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