std::experimental::static_pointer_cast, std::experimental::dynamic_pointer_cast, std::experimental::const_pointer_cast, std::experimental::reinterpret_pointer_cast
From cppreference.com
< cpp | experimental | shared ptr
| template< class T, class U > std::experimental::shared_ptr<T> static_pointer_cast( const std::experimental::shared_ptr<U>& r ) noexcept; |
(1) | (library fundamentals TS) |
| template< class T, class U > std::experimental::shared_ptr<T> dynamic_pointer_cast( const std::experimental::shared_ptr<U>& r ) noexcept; |
(2) | (library fundamentals TS) |
| template< class T, class U > std::experimental::shared_ptr<T> const_pointer_cast( const std::experimental::shared_ptr<U>& r ) noexcept; |
(3) | (library fundamentals TS) |
| template< class T, class U > std::experimental::shared_ptr<T> reinterpret_pointer_cast( const std::experimental::shared_ptr<U>& r ) noexcept; |
(4) | (library fundamentals TS) |
Creates a new instance of std::experimental::shared_ptr whose stored pointer is obtained from r's stored pointer using a cast expression. If r is empty, so is the new shared_ptr (but its stored pointer is not necessarily null).
Otherwise, the new shared_ptr will share ownership with r, except that it is empty if the dynamic_cast performed by dynamic_pointer_cast returns a null pointer.
Let Y be typename std::experimental::shared_ptr<T>::element_type, then the resulting std::experimental::shared_ptr's stored pointer will be obtained by calling (in respective order):
1) static_cast<Y*>(r.get()).
2) dynamic_cast<Y*>(r.get()) (If the result of the
dynamic_cast is a null pointer value, the returned shared_ptr will be empty).3) const_cast<Y*>(r.get()).
4) reinterpret_cast<Y*>(r.get()).
The behavior of these functions is undefined unless the corresponding cast from U* to T* is well formed:
1) The behavior is undefined unless static_cast<T*>((U*)nullptr) is well formed.
2) The behavior is undefined unless dynamic_cast<T*>((U*)nullptr) is well formed.
3) The behavior is undefined unless const_cast<T*>((U*)nullptr) is well formed.
4) The behavior is undefined unless reinterpret_cast<T*>((U*)nullptr) is well formed.
Parameters
| r | - | The pointer to convert |
Example
| This section is incomplete Reason: no example |
See also
constructs new shared_ptr (public member function) | |
| applies static_cast, dynamic_cast, const_cast, or reinterpret_cast to the stored pointer (function template) |