[Development] Qt Coding style and C++11

[Shawn Rutledge]

> On 18 Sep 2017, at 09:37, André Somers <andre at familiesomers.nl> wrote:
> 
> Op 18/09/2017 om 09:02 schreef Lorn Potter:
>>> On 15 Sep 2017, at 6:47 pm, Kevin Funk <kevin.funk at kdab.com> wrote:
>>> 
>>> (2) And maybe your request:
>>> - Use C++11 member initialization where possible
>>> (IOW: Run clang-tidy cppcoreguidelines-pro-type-member-init checker
>>> on code base and apply all fixes)
>> But then files will begin to have a mixture of the two conventions, which is not necessarily a good thing. Wide scale changing of this is probably not a good idea.
> I don't get this. Wouldn't doing this do as much cleanup as is
> reasonably possible across the whole code base? How do you end up with a
> mixture then?

I’m not sure what Lorn meant, but there are cases where you can’t do the initialization along with the declaration: for example bitfields.  Or when the initialization needs to be different in different constructors.  So as long as we accept that it will never be 100%, I think it doesn’t hurt to use it where we can.

>>> I personally think that (1) would be useful (despite it costing us a lot of 
>>> code churn when doing the transition) because it's much easier to read 
>>> `nullptr` than `Q_NULLPTR`, or `override` instead of `Q_DECL_OVERRIDE` in 
>>> code. Other opinions may vary, but it's definitely more comfortable for 
>>> newcomers to read familiar C++ keywords than custom macros.
>>> 
>>> I'd be willing to provide the patches for (1) and maybe even (2) if there's a 
>>> clear sentiment towards the change(s).

+1 yes please… I always do (1) in new code and strongly encourage it in code reviews, for a long time already.

> It is less error-phrone to initialize at the place of declaration,
> instead of in a different file. This gets worse if you have multiple
> constructors. So, naturally, we end up with uninitialized member
> variables, with all the mahem that may cause.

Yep; and the lazy reason to like it is that you don’t have to worry about keeping initialization in the same order as declaration, with all the $#@% warnings if you don’t.  (If this pedantry is so important, why can’t it be automated?  And now it finally is.)

Slight downside: it’s going to make merges harder for a while.  I guess we will do such wholesale changes only on dev branch?