The title pretty much sums up my question.
The deprecation and removal of case class inheritance is a pretty new one, and I wonder which things got removed/substantially changed before that. I remember something about val in for loops and a different name for object as well as some requires keyword.
I would love to see code examples of how things were used/how they were replaced later, with an actual version when it happened and with a rationale why!
PS: One item per answer seems to be a good idea!
It was possible in Scala 2.7 to declare things of type int (no capital "I"). Since Scala does not support the idea of primitive values and tries to be as consistent with everything as far as it can, this "feature" is deprecated.