std::shared_ptr<T>::operator=
Declarations
// 1)
shared_ptr& operator=( const shared_ptr& r ) noexcept;
template< class Y >
shared_ptr& operator=( const shared_ptr<Y>& r ) noexcept;
// 2)
shared_ptr& operator=( shared_ptr&& r ) noexcept;
template< class Y >
shared_ptr& operator=( shared_ptr<Y>&& r ) noexcept;
// 3)
template< class Y >
shared_ptr& operator=( std::auto_ptr<Y>&& r ); // deprecated in C++11, removed in C++17
// 4)
template< class Y, class Deleter >
shared_ptr& operator=( std::unique_ptr<Y,Deleter>&& r );
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.
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, and 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
3-4) May throw implementation-defined exceptions.