std::experimental::weak_ptr<T>::weak_ptr

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Technical specifications
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constexpr weak_ptr() noexcept;
(1) (library fundamentals TS)
weak_ptr( const weak_ptr& r ) noexcept;
(2) (library fundamentals TS)
template< class Y >
weak_ptr( const weak_ptr<Y>& r ) noexcept;
(2) (library fundamentals TS)
template< class Y >
weak_ptr( const std::experimental::shared_ptr<Y>& r ) noexcept;
(2) (library fundamentals TS)
weak_ptr( weak_ptr&& r ) noexcept;
(3) (library fundamentals TS)
template< class Y >
weak_ptr( weak_ptr<Y>&& r ) noexcept;
(3) (library fundamentals TS)

Constructs a new weak_ptr that potentially shares an object with r.

1) Default constructor. Constructs empty weak_ptr.
2) Constructs new weak_ptr which shares an object managed by r. If r manages no object, *this manages no object too. The templated overloads don't participate in overload resolution unless either Y* is implicitly convertible to T*, or Y is the type "array of N U" for some type U and some number N, and T is the type "array of unknown bound of (possibly cv-qualified) U".
3) Move constructors. Moves a weak_ptr instance from r into *this. After this, r is empty and r.use_count() == 0. The templated overload doesn't participate in overload resolution unless either Y* is implicitly convertible to T*, or Y is the type "array of N U" for some type U and some number N, and T is the type "array of unknown bound of (possibly cv-qualified) U".

Parameters

r - a std::experimental::shared_ptr or std::experimental::weak_ptr that will be viewed by this std::experimental::weak_ptr

Exceptions

noexcept specification:  
noexcept
  

Example

See also

creates a new weak_ptr
(public member function of std::weak_ptr<T>)
assigns the weak_ptr
(public member function of std::weak_ptr<T>)