Re: Virtual Ctor Idiom and auto_ptr
* Yechezkel Mett:
Alf P. Steinbach wrote:
class Base
{
private:
virtual Base* cloneImpl() const
{ return new Base( *this ); }
public:
typedef std::auto_ptr<Base> AutoPtr;
virtual ~Base() {}
virtual AutoPtr virtualClone() const
{
return AutoPtr( cloneImpl() );
}
AutoPtr clone() const { return AutoPtr( cloneImpl() ); }
};
class Derived: public Base
{
private:
virtual Derived* cloneImpl() const
{ return new Derived( *this ); }
public:
typedef std::auto_ptr<Derived> AutoPtr;
virtual Base::AutoPtr virtualClone() const
{
return Base::AutoPtr( cloneImpl() );
}
AutoPtr clone() const { return AutoPtr( cloneImpl() ); }
};
Why do you need virtualClone()? clone() seems to give everything needed.
You're 100% right.
I don't recall why I wrote that (virtualClone) code in the first place:
it should have been removed before I hit "Send".
Sorry 'bout that.
Cheers,
- Alf
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