std::auto_ptr::auto_ptr
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                    | explicit auto_ptr( X* p = 0 ); | (1) | (deprecated) | 
| auto_ptr( auto_ptr& r ); | (2) | (deprecated) | 
| template< class Y > auto_ptr( auto_ptr<Y>& r ); | (3) | (deprecated) | 
| template< class Y > auto_ptr( auto_ptr_ref<Y> m ); | (4) | (deprecated) | 
Constructs the auto_ptr from a pointer that refers to the object to manage.
1) Constructs the 
auto_ptr with pointer p.2) Constructs the 
auto_ptr with the pointer held in r. r.release() is called to acquire the ownership of the object.3) Same as (2). Y* must be implicitly convertible to T*.
4) Constructs the 
auto_ptr with the pointer held in the auto_ptr instance referred to by m. p.release() is called for the auto_ptr p that m holds to acquire the ownership of the object. auto_ptr_ref is an implementation-defined type that holds a reference to auto_ptr. std::auto_ptr is implicitly convertible to and assignable from this type. The implementation is allowed to provide the template with a different name or implement equivalent functionality in other ways.[edit] Parameters
| p | - | a pointer to an object to manage | 
| r | - | another auto_ptrto transfer the ownership of the object from | 
| m | - | an implementation-defined type that holds a reference to auto_ptr | 
[edit] Exceptions
(none)
[edit] 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.


