[Interest] QSharedDataPointer detach too much ( don't call const )

[Philippe]

This is a (logical) C++ aspect, not a Qt thing:
non-constant pointers call non-contant methods in priority.

Philippe

On Thu, 20 Sep 2018 11:02:44 +0200
Michal Lazo <xlazom00 at gmail.com> wrote:

I still don't see reason why compiler don't call const variants to access raw pointer 
> http://code.qt.io/cgit/qt/qtbase.git/tree/src/corelib/tools/qshareddata.h#n76
> 
> 
> 
> for example here(QTextCursor)
> http://code.qt.io/cgit/qt/qtbase.git/tree/src/gui/text/qtextcursor.cpp#n1151
> 
> I would expect calling const variant and I think that author of that lines expect same.
> 
> 
> 
> 
> On Thu, Sep 20, 2018 at 10:55 AM Philippe <philwave at gmail.com> wrote:
> 
>> You just have to change your line:
>> 
>> Car * carPtr = &car;
>> 
>> with
>> 
>> const Car * carPtr = &car;
>> 
>> Philippe
>> 
>> On Thu, 20 Sep 2018 10:40:01 +0200
>> Michal Lazo <xlazom00 at gmail.com> wrote:
>> 
>>> 
>>> Hello
>>> example
>>> https://pastebin.com/xL9yWhKe
>>> 
>>> 
>>> 
>>> I never used QSharedDataPointer in my code but is is heavily used in Qt
>>> My problem is that I found that QSharedDataPointer prefer non const operator for access raw pointer to object instead of const variant.
>>> And at the end non const variant call detach() = cloning object
>>> Look at my example and plz debug if conditions
>>> 
>>> 
>>> I use compiler MSVC 2015, 2017
>>> 
>>> 
>>> My problem is that for example QTextCursor use this constructions and it heavily call detach. And simple call const variant of method should fix this.
>>> 
>>> 
>>> Anybody can explain this behaviour?  
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 


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