std::shared_ptr::operator=

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Dynamic memory management
Uninitialized storage
(C++17)
(deprecated since c++17)
(deprecated since c++17)
(deprecated since c++17)
Garbage collection support
Miscellaneous
(C++11)
(C++11)
C Library
Low level memory management
 
 
shared_ptr& operator=( const shared_ptr& r );
(1)
template< class Y >
shared_ptr& operator=( const shared_ptr<Y>& r );
(1)
shared_ptr& operator=( shared_ptr&& r );
(2)
template< class Y >
shared_ptr& operator=( shared_ptr<Y>&& r );
(2)
template< class Y >
shared_ptr& operator=( std::auto_ptr<Y>&& r );
(3)
template< class Y, class Deleter >
shared_ptr& operator=( std::unique_ptr<Y,Deleter>&& r );
(4)

Replaces the managed object with the one managed by r.

If *this already owns an object and it is the last shared_ptr owning it, and r is not the same as *this, the object is destroyed through the owned deleter.

1) Shares ownership of the object managed by r. If r manages no object, *this manages no object too. Equivalent to shared_ptr<T>(r).swap(*this).

2) Move-assigns a shared_ptr from r. After the assignment, *this contains a copy of the previous state of r, r is empty. Equivalent to shared_ptr<T>(std::move(r)).swap(*this).

3) Transfers the ownership of the object managed by r to *this. If r manages no object, *this manages no object too. After the assignment, *this contains the pointer previously held by r, and use_count()==1; also r is empty. Equivalent to shared_ptr<T>(r).swap(*this).

4) Transfers the ownership of the object managed by r to *this. The deleter associated to r is stored for future deletion of the managed object. r manages no object after the call. Equivalent to shared_ptr<T>(std::move(r)).swap(*this).

Parameters

r - another smart pointer to share the ownership to or acquire the ownership from

Return value

*this

Notes

The implementation may meet the requirements without creating a temporary shared_ptr object.

Exceptions

1-2)
noexcept specification:  
noexcept
  

3) (none)

4) may throw exception

Example

See also

replaces the managed object
(public member function)