[Development] Changes to QObject::connect and other functor-taking API implementations

[Volker Hilsheimer]

Hi,


What started as an attempt to provide a few building blocks for making it easier to build asynchronous APIs taking any kind of callable (like QTimer::singleShot or QHostInfo::lookupHost) [1] has turned into a bit of a longer journey to the core.

[1] https://codereview.qt-project.org/c/qt/qtbase/+/470341
[2] https://codereview.qt-project.org/c/qt/qtbase/+/475168

Thanks to input and reviews from Thiago, Mårten, and others, the code of QObject::connect has now been simplified quite a bit as well.

[3] https://codereview.qt-project.org/c/qt/qtbase/+/475169/8
[4] https://codereview.qt-project.org/c/qt/qtbase/+/475174


Thanks to the very through coverage of those code-paths in qtbase code and tests I’m fairly confident that this should go fairly unnoticed for submodules and existing applications. Nevertheless, more testing and reviewing is always a good thing for changes to these APIs.

So, great if you want to start with an early header review for those APIs in particular, and if you run into any problems with your code after these changes, please file a P0 JIRA ticket for me.


Cheers,
Volker