> On 16 Jul 2020, at 18:45, Thiago Macieira <thiago.macie...@intel.com> wrote: > > On Thursday, 16 July 2020 08:40:35 PDT Volker Hilsheimer wrote: >> action->text = document->title; // still no binding >> action->text = Qt::makePropertyBinding(document->title); // yay binding! >> >> >> These struct-methods are either inline forwards, or implemented by moc, and >> we need a differently named but identical struct for each property. >> >> The struct has no data itself, so ideally would be of size zero. > > That didn't answer how they can share an address. Suppose I have two > properties of type QString called "text" and "title". > > action->text = "foo"; > action->title = "bar"; > > Since std::is_same_v<decltype(action->text), decltype(action->title)> and > &action->text == &action->title, how does the code above even work?
action->text.structMemberFunction(); calls QAction::_qt_property_api_text::structMemberFunction, which is implemented by moc to operate on d->text whereas action->title.structMemberFunction(); calls QAction::_qt_property_api_title::structMemberFunction, which is implemented by moc to operate on d->title. The structMemberFunctions are different for each property, but that doesn't increase the size of QAction instances. The relevant macros are defined in qtmetamacros.h. Volker _______________________________________________ Development mailing list Development@qt-project.org https://lists.qt-project.org/listinfo/development
