Boost logo

Boost :

From: Sebastian Redl (sebastian.redl_at_[hidden])
Date: 2006-03-09 15:03:38

Ralf W. Grosse-Kunstleve wrote:

>In contrast to the STLport implementation I use this approach to implement the
>copy constructor (and similarly for the assignment operator):
> class auto_array
> {
> mutable T* ptr;
> auto_array(auto_array const& other)
> {
> ptr = const_cast<auto_array*>(&other)->release();
> }
> };
>I know it works on a large number of platforms (several versions of EDG, VC,
>g++). valgrind also didn't have any complaints. Is the approach also OK from a
>theoretical viewpoint?
I don't know about STLport's approach, but const-casting the parameter
is definitely not OK from a theoretical viewpoint. Your const parameter
is a promise that you won't modify the parameter, but then you go ahead
and do it anyway.
You should make the parameter non-const, like the GNU C++ library does
with auto_ptr:
auto_ptr(auto_ptr& __a) throw() : _M_ptr(__a.release()) { }

Sebastian Redl

Boost list run by bdawes at, gregod at, cpdaniel at, john at