[Development] Lack of base classes/interfaces? Q*, Q*F

[Jason H]

I am wondering why all the Q* and Q*F classes (where $1 in [Rect, Point, etc]) don't use an interface? I recently moved some code from ints to floats, and I had to change far more code than I should have had to.

My proposal is to change QRect to QRectI, and make QRect an interface.

In the past, I think I remember some pain points between QList and QVector, (or was it QMap, QHash?) which should be QIterable (QIndexable)? Similarly all the string types. 

I'm not fan of MS's Ieverything, but I think base classes/interfaces are under used in Qt. Why aren't there more of them?