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From: Schoenborn, Oliver (Oliver.Schoenborn_at_[hidden])
Date: 2002-10-07 09:18:21

> -----Original Message-----
> From: Daniel Frey [mailto:daniel.frey_at_[hidden]]
> I haven't followed the discussion closely, so please forgive if this has
> been suggested before or if I misunderstood the problem. You want ptr<T>
> to be usable as a ptr< const T >? What about:
> template< typename T > class ptr
> {
> ...
> public:
> operator const ptr< const T >&() const
> {
> return reinterpret_cast< const ptr< const T >& >( *this );
> }
> ...
> };
> Or is reinterpret_cast considered too
> dangerous/non-portable/...? For my
> own pointer-class, this works well (GCC 3.2).

Interesting, I'd like to know if there are any situations where it is not
safe. Since the member data and functions for T and const T are exactly the
same perhaps this is safe. But I would guess that unless something like that
is specified in the standard (about the action of reinterpret_cast on
template classes of T vs on const T), it's probably non-portable in theory
(though in practice it may be). Hopefully some of the experts on the list
will share their opinions. Have you posted this to other newsgroups like


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