On Wed, Nov 25, 2020 at 07:40:48AM +0100, Markus Armbruster wrote: > Eduardo Habkost <ehabk...@redhat.com> writes: > > > On Tue, Nov 24, 2020 at 04:20:37PM +0100, Markus Armbruster wrote: > >> Eduardo Habkost <ehabk...@redhat.com> writes: > >> > >> > On Tue, Nov 24, 2020 at 09:49:30AM +0100, Markus Armbruster wrote: > >> >> Eduardo Habkost <ehabk...@redhat.com> writes: > >> >> > >> >> > On Mon, Nov 23, 2020 at 08:51:27AM +0100, Markus Armbruster wrote: > >> >> >> Eduardo Habkost <ehabk...@redhat.com> writes: > >> >> >> > >> >> >> > On Fri, Nov 20, 2020 at 06:29:16AM +0100, Markus Armbruster wrote: > >> >> >> [...] > >> >> >> >> When the structure of a data type is to be kept away from its > >> >> >> >> users, I > >> >> >> >> prefer to keep it out of the public header, so the compiler > >> >> >> >> enforces the > >> >> >> >> encapsulation. > >> >> >> > > >> >> >> > I prefer that too, except that it is impossible when users of the > >> >> >> > API need the compiler to know the struct size. > >> >> >> > >> >> >> There are cases where the structure of a data type should be > >> >> >> encapsulated, yet its size must be made known for performance (avoid > >> >> >> dynamic memory allocation and pointer chasing). > >> >> >> > >> >> >> Need for encapsulation correlates with complex algorithms and data > >> >> >> structures. The cost of dynamic allocation is often in the noise > >> >> >> then. > >> >> > > >> >> > I don't know what we are talking about anymore. None of this > >> >> > applies to the QNum API, right? > >> >> > > >> >> > QNum/QNumValue are not complex data structures, and the reason we > >> >> > need the compiler to know the size of QNumValue is not related to > >> >> > performance at all. > >> >> > >> >> We started with the question whether to make QNumValue's members > >> >> private. We digressed to the question when to make members private. > >> >> So back to the original question. > >> >> > >> >> > We might still want to discourage users of the QNum API from > >> >> > accessing QNum.u/QNumValue.u directly. Documenting the field as > >> >> > private is a very easy way to do it. > >> >> > >> >> It's a complete non-issue. QNum has been around for years, and we > >> >> haven't had any issues that could've been plausibly avoided by asking > >> >> people to refrain from accessing its members. > >> >> > >> >> If there was an actual need to keep the members private, I'd move the > >> >> struct out of the header, so the compiler enforces privacy. > >> > > >> > Understood. There's still a question I'd like to answer, to > >> > decide how the API documentation should look like: > >> > > >> > Is QNum.u/QNumValue.u required to be part of the API > >> > documentation? > >> > > >> > If accessing that field directly is not necessary for using the > >> > API, I don't think it should appear in the documentation (because > >> > it would be just noise). > >> > >> The current patch's comment on QNumValue looks good to me. > >> > >> Does this answer your question? > > > > The current patch (v3) doesn't address the question. It doesn't > > include documentation for the field, but doesn't hide it. > > kernel-doc will print a warning on that case. > > Do we care?
Yes. Peter will reject pull requests if it generates kernel-doc warnings. > How many such warnings exist before the patch? Zero. > Does this series add just this one, or more? The current series (v3) doesn't add any, because I dropped the patch that added QObject and QNum documentation to docs/devel. I still want to resubmit that patch later, though. > > Use your judgement, then be ready to explain it :) OK! -- Eduardo