[Kde-bindings] Qyoto Delegate Patch

[Arno Rehn]

Am Donnerstag, 12. Juli 2007 schrieb Richard Dale:
> On Thursday 12 July 2007, Arno Rehn wrote:
> > Hi,
> >
> > based on the discussion Richard and I had at akademy about signals
> > mapping onto delegates, I hacked kalyptus to generate generic delegates
> > but keep the various overloaded 'Connect' methods. In my opinion it's
> > simply the less ugliest possibility.
> >
> > Now you can say:
> > Connect(button, SIGNAL("clicked(bool)"), delegate(bool b) {
> > 	Console.WriteLine("Bool {0}", b);
> > });
> >
> > or
> > button.AddClickedHandler(delegate(bool b) {
> > 	Console.WriteLine("Bool {0}", b);
> > });
> >
> > Instead of an anonymous delegate you could of course give a normal method
> > to the functions.
> >
> > The other possibility would have been to make also the Connect method
> > generic, which would then look like this:
> > Connect<bool>(button, SIGNAL("clicked(bool)"), delegate(bool b) {
> > 	Console.WriteLine("Bool {0}", b);
> > });
> >
> > With this version we would have to check what delegate type the
> > programmer actually used and then connect to the appropiate imternal
> > slot. So the actual amount of code generated wouldn't decrease, we'd only
> > have less overloaded 'Connect' methods.
> > Personally spoken, I think the first version without a generic Connect is
> > much nicer.
> > I uploaded a patch here since it's quite a large one:
> > http://pumphaus.kilu.de/programming/delegate_patch.patch
> > It also adds a new option to the CMakeLists.txt with which you can
> > enable/disable the new experimental API (ENABLE_QYOTO_EXPERIMENTAL,
> > disabled by default). Patch from the top level kdebindings directory,
> > with -p0.
>
> I'm not keen on 100 or so extra connect methods polluting a public class
> like QObject, and so I prefer the generic version. I think most uses of
> this form of Connect would be with no args, or just an int arg. This is why
> I think it was a good idea to not rush into adding delegate things to the
> first release of Qyoto. If we have users, we can talk about use cases -
> otherwise it is a bit hard to judge which is the least ugly solution.
Yeah, because of this I didn't check this in.

> Arno - now that kdedevelopers.org is hosted on a KDE Ev machine which won't
> go missing, how about getting an account and blogging about this sort of
> issue? Also a blog somewhere about how non-C# language work with Qyoto
> would be really interesting. Then you would need to contact clee to get the
> blog aggregated on kde planet org.
I didn't know kdedevelopers.org is online again. I thought about blogging on 
that issue but failed to look whether kdedevelopers.org is online again.
It will the first thing I'll do tomorrow ;)

-- 
Arno Rehn
arno at arnorehn.de