From: John (john_at_[hidden])
Date: 2008-06-24 11:13:03
Thanks, I did see that in the archives before I posted. Please correct me if I'm
wrong, but the code from 2003 doesn't provide a solution, since the clone()
method is not virtual. i.e., you can't do this with it:
shared_ptr<A> a = foo();
shared_ptr<A> a2 = a->clone ();
which is the goal of the pattern.
Frank Mori Hess wrote:
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> On Tuesday 24 June 2008 09:43 am, John wrote:
>> This pattern/idiom is well-established:
>>
>> struct A {
>> virtual A* clone () = 0;
>> };
>>
>> struct B : public A {
>> virtual B* clone ();
>> };
>>
>>
>> But the above does not work when the pointers A* and B* are replaced by
>> shared_ptr<A> and shared_ptr<B>:
>>
>> struct A {
>> virtual shared_ptr<A> clone () = 0;
>> };
>>
>> struct B : public A {
>> virtual shared_ptr<B> clone ();
>> };
>>
>>
>> Is there a workaround? Another way to solve the same problem? Thanks!
>
> See:
>
> http://listarchives.boost.org/boost-users/2003/02/2996.php
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