[Development] Namespaces (was: Qt Platform Extras)

[Saether Jan-Arve]

> -----Original Message-----
> From: development-bounces+jan-arve.saether=digia.com at qt-project.org
> [mailto:development-bounces+jan-arve.saether=digia.com at qt-project.org]
> On Behalf Of Nurmi J-P
> Sent: 16. september 2013 12:49
> To: development at qt-project.org
> Subject: [Development] Namespaces (was: Qt Platform Extras)
> 
> On Sep 14, 2013, at 2:56 AM, Sze Howe Koh <szehowe.koh at gmail.com> wrote:
> 
>> On 11 September 2013 01:07, Laszlo Papp <lpapp at kde.org> wrote:
>>> On Tue, Sep 10, 2013 at 4:46 PM, Thiago Macieira
>>> <thiago.macieira at intel.com>
>>> wrote:
>>>> 
>>>> On terça-feira, 10 de setembro de 2013 22:31:53, Sze Howe Koh wrote:
>>>>> On 10 September 2013 14:27, Knoll Lars <Lars.Knoll at digia.com>
> wrote:
>>>>>> Ok, let's use QtWin for the namespace. For the module itself it
>>>>>> makes IMO to keep the 'Extras' in the name.
>>>>>> 
>>>>>> Cheers,
>>>>>> Lars
>>>>> 
>>>>> QtWin or QWin?
>>>> 
>>>> QtWin, it's a namespace.
>>> 
>>> 
>>> I believe he is aware of that...
>>> 
>>> I think, Sze please correct me if I am wrong, he just wanted to
>>> make sure because there was several emails last year about QFoo or
>>> QtFoo for the namespace, and it seemed that the suboptimal naming
>>> was chosen for other reasons.
>> 
>> Laszlo is correct.
>> 
>> Before Qt 5 was released, most public namespaces had the "QFoo" format
>> -- QSsl, QDBus, QAudio, etc. A few had the "QtFoo format --
>> QtMultimedia::MetaData (unreleased), QtMultimedia (unreleased), and
>> QtConcurrent. I suggested making them uniform. [1]
>> 
>> Lars said that he preferred "QFoo" -> "QtFoo", but that change was the
>> much more intrusive one. Qt 5 was close to Beta 2 at the time, so he
>> chose the lower-risk "QtFoo" -> "QFoo". [2]
>> 
>> As of Qt 5.1, all public namespaces are "QFoo", except "Qt" and
>> "QtConcurrent". Thiago blocked the latter on the basis that (i)
>> development on that module has stopped, and (ii) QtConcurrent is quite
>> different from all the other namespaces anyway. [3]
>> 
>> With all that in mind, do we want "QtWin" or "QWin"? The benefit of
>> "QWin" is consistency with existing conventions; the downside is having
>> to wait till Qt 6 if we want to switch to the preferred "QtFoo".
>> "QtWin" has the benefit of introducing users to the preferred naming
>> convention now (and a smaller list of namespace changes if/when the
>> change occurs), at the cost of introducing more inconsistencies.
>> 
>> I vote for "QWin" for consistency, and I'm not sure that an extra
>> ':%s/QWin::/QtWin::/g' will make a difference to users if they're
>> doing the same for all other namespaces in Qt 6.
> 
> Consistent or not, do we want to introduce more namespaces with
> suboptimal names? IMHO it would be better to go for the optimal naming
> with new namespaces, and eventually fix the old remaining ones in Qt 6.
> That would give us cute names and less changes needed in the future
> while porting to Qt 6.
> 
> One could also argue whether for example the QSsl namespace is that
> bad after all. The scope of that particular namespace is to provide
> enums for a small set of SSL classes, whereas namespaces like QtWin
> and QtMac are module-wide. To me it would make sense to enforce the
> QtFoo naming convention for such module-wide enums, but still allow
> QFoo style naming for "targeted" namespaces.
>
I think I agree with JP. AFAICS, no other module is using module-wide namespaces, so it would not be inconsistent to name it QtFoo.

Also, using QtFoo makes it consistent with the module-wide include:
#include <QtFoo>

(And it cannot be #include <QFoo> since that would be inconsistent with our other module-wide includes)

Jan Arve