Generator / Visitor version of QObject::findChildren

QObject::findChildren returns a QList of the objects that match the search criteria.

One could instead imagine

1. a visitChildren function:

object->visitChildren<QLabel *>(QString(), [](QLabel *label) { label->setText("42"); });

2. a generator API:

for (QLabel *label : object->children<QLabel *>())  // not sure about a good name here
  label->setText("42");

Because if the point is to do an action for each child found this way, then one doesn't need to allocate and return a QList of results.

Do we want both? Only 2.?