On Sat, Apr 08, 2006 at 12:11:51AM -0400, David Menendez wrote:

...

newtype ArithException a = ArithException a

data DivideByZero

throw (ArithException DivideByZero)

your code:

data MultiplyByZero throw (ArithException MultiplyByZero)

How would you use this to write a handler that captures any ArithException?

You would use the Typeable1 class in Data.Typeable. not perfect, but exception hierarchies shouldn't be too deep so it is not so bad. John -- John Meacham - ⑆repetae.net⑆john⑈