std::shared_ptr<T>:: operator=

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C++
Utilities library
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(C++11) (until C++23)
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(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)



std::shared_ptr
Member functions
shared_ptr::operator=
Modifiers
Observers
(C++17)
( until C++20* )
(C++26)
(C++26)
Non-member functions
(C++20)
(C++20)
(C++17)
(until C++20) (until C++20) (until C++20) (until C++20) (until C++20) (C++20)
functions ( until C++26* )
Helper classes
(C++20)
Deduction guides (C++17)
shared_ptr & operator = ( const shared_ptr & r ) noexcept ;
(1)
template < class Y >
shared_ptr & operator = ( const shared_ptr < Y > & r ) noexcept ;
(2)
shared_ptr & operator = ( shared_ptr && r ) noexcept ;
(3)
template < class Y >
shared_ptr & operator = ( shared_ptr < Y > && r ) noexcept ;
(4)
template < class Y >
shared_ptr & operator = ( std:: auto_ptr < Y > && r ) ;
(5) (deprecated in C++11)
(removed in C++17)
template < class Y, class Deleter >
shared_ptr & operator = ( std:: unique_ptr < Y, Deleter > && r ) ;
(6)

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.

1,2) 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 ) .
3,4) 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 ) .
5) 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 ) .
6) 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

5,6) May throw implementation-defined exceptions.

Example

This section is incomplete
Reason: no example

See also

replaces the managed object
(public member function)
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