# std::auto_ptr<T>::operator=

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< cpp‎ | memory‎ | auto ptr

auto_ptr& operator=( auto_ptr& r ) throw(); | (1) | (deprecated in C++11) (removed in C++17)
template< class Y > auto_ptr& operator=( auto_ptr<Y>& r ) throw(); | (2) | (deprecated in C++11) (removed in C++17)
auto_ptr& operator=( auto_ptr_ref<T> m ) throw(); | (3) | (deprecated in C++11) (removed in C++17)

Replaces the managed object with the one managed by r or m.

1) Effectively calls reset(r.release()).
2) Effectively calls reset(r.release()). `Y*` must be implicitly convertible to `T*`.
3) Effectively calls reset(m.release()). `auto_ptr_ref` is an implementation-defined type that holds a reference to `auto_ptr`. std::auto_ptr is implicitly convertible to and from this type. The implementation is allowed to provide the template with a different name or implement equivalent functionality in other ways.

### Parameters

r | - | another `auto_ptr` to transfer the ownership of the object from
m | - | an object of implementation-defined type that holds a reference to `auto_ptr`

### Return value

*this.

### Notes

The constructor and the copy assignment operator from `auto_ptr_ref` is provided to allow copy-constructing and assigning std::auto_ptr from nameless temporaries. Since its copy constructor and copy assignment operator take the argument as non-const reference, they cannot bind rvalue arguments directly. However, a user-defined conversion can be executed (which releases the original `auto_ptr`), followed by a call to the constructor or copy-assignment operator that take `auto_ptr_ref` by value. This is an early implementation of move semantics.

### Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR | Applied to | Behavior as published | Correct behavior
--- | --- | --- | ---
LWG 127 | C++98 | `auto_ptr` was not assignable from `auto_ptr_ref` | added overload (3)

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