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GeneralRe: Invalidate problem Pin
dlhson17-Aug-02 9:09
dlhson17-Aug-02 9:09 
Questionhow to get access to accept null values through code? Pin
nss16-Aug-02 17:09
nss16-Aug-02 17:09 
AnswerRe: how to get access to accept null values through code? Pin
Todd Smith16-Aug-02 17:32
Todd Smith16-Aug-02 17:32 
GeneralRe: how to get access to accept null values through code? Pin
nss16-Aug-02 18:08
nss16-Aug-02 18:08 
GeneralRe: how to get access to accept null values through code? Pin
nss16-Aug-02 18:13
nss16-Aug-02 18:13 
GeneralA strange compiler error C2440 Pin
IFREETA16-Aug-02 13:56
IFREETA16-Aug-02 13:56 
GeneralRe: A strange compiler error C2440 Pin
Daniel Lohmann16-Aug-02 21:34
Daniel Lohmann16-Aug-02 21:34 
GeneralRe: A strange compiler error C2440 Pin
Stuart Dootson17-Aug-02 0:30
professionalStuart Dootson17-Aug-02 0:30 
You're dead right - it's because the auto_ptr copy constructor takes a non-const reference. The reason it's like that (i.e. not using mutable on the ownership flag) is that containers require that their content elements can be copied without altering the element being copied. For example (and I'm quoting Herb Sutter's Exceptional C++), sort algorithms (particularly those based on partitioning & sorting, I suspect) take copies of elements of containers. This would result in the element being deleted, but it's reference still being in the container.

auto_ptr is really best used as a scoped pointer container, i.e. without transfer of ownership. It does help make things easier then, especially with helping to ensure exception safety.

Stuart Dootson

'Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p'
GeneralRe: A strange compiler error C2440 Pin
Daniel Lohmann17-Aug-02 11:27
Daniel Lohmann17-Aug-02 11:27 
GeneralRe: A strange compiler error C2440 Pin
IFREETA17-Aug-02 1:57
IFREETA17-Aug-02 1:57 
GeneralRe: A strange compiler error C2440 Pin
dlhson17-Aug-02 9:12
dlhson17-Aug-02 9:12 
GeneralNot so simple Pin
IFREETA17-Aug-02 3:28
IFREETA17-Aug-02 3:28 
GeneralRe: Not so simple Pin
Daniel Lohmann17-Aug-02 11:30
Daniel Lohmann17-Aug-02 11:30 
GeneralRe: Not so simple Pin
Stuart Dootson17-Aug-02 11:35
professionalStuart Dootson17-Aug-02 11:35 
GeneralRe: A strange compiler error C2440 Pin
Stuart Dootson17-Aug-02 21:59
professionalStuart Dootson17-Aug-02 21:59 
GeneralRe: A strange compiler error C2440 Pin
Mike Nordell17-Aug-02 23:25
Mike Nordell17-Aug-02 23:25 
GeneralNeed a help with CDialog and WM_QWERYENDSESSION Pin
Pavel Sokolov16-Aug-02 13:19
Pavel Sokolov16-Aug-02 13:19 
GeneralRe: Need a help with CDialog and WM_QWERYENDSESSION Pin
Daniel Ferguson16-Aug-02 21:05
Daniel Ferguson16-Aug-02 21:05 
GeneralRe: Need a help with CDialog and WM_QWERYENDSESSION Pin
Pavel Sokolov17-Aug-02 0:16
Pavel Sokolov17-Aug-02 0:16 
GeneralReal document in View Pin
RocardoS16-Aug-02 13:00
sussRocardoS16-Aug-02 13:00 
GeneralMFC newbie needs help with CString Pin
Raskolnikov16-Aug-02 12:42
Raskolnikov16-Aug-02 12:42 
GeneralRe: MFC newbie needs help with CString Pin
valikac16-Aug-02 13:14
valikac16-Aug-02 13:14 
GeneralRe: MFC newbie needs help with CString Pin
Christian Graus16-Aug-02 13:19
protectorChristian Graus16-Aug-02 13:19 
GeneralCString Trim Pin
Shotgun16-Aug-02 12:26
Shotgun16-Aug-02 12:26 
GeneralRe: CString Trim Pin
Michael Dunn16-Aug-02 12:32
sitebuilderMichael Dunn16-Aug-02 12:32 

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