scala 2.8 control Exception - what is the point?

Question

In the upcoming scala 2.8, a util.control package has been added which includes a break library and a construct for handling exceptions so that code which looks lik

Answer 1

As the guy who wrote it, the reasons are composition and encapsulation. The scala compiler (and I am betting most decent sized source bases) is littered with places which swallow all exceptions -- you can see these with -Ywarn-catches -- because the programmer is too lazy to enumerate the relevant ones, which is understandable because it's annoying. By making it possible to define, re-use, and compose catch and finally blocks independently of the try logic, I hoped to lower the barrier to writing sensible blocks.

And, it's not exactly finished, and I'm working on a million other areas too. If you look through the actors code you can see examples of huge cut-and-pasted multiply-nested try/catch/finally blocks. I was/am unwilling to settle for try { catch { try { catch { try { catch ...

My eventual plan is to have catch take an actual PartialFunction rather than require a literal list of case statements, which presents a whole new level of opportunity, i.e. try foo() catch getPF()