On Fri, Apr 07, 2006 at 03:49:40PM +0100, Simon Marlow wrote: > John, have you seen this? > > http://haskell.galois.com/cgi-bin/haskell-prime/trac.cgi/wiki/Extensible > Exceptions
Yes, and maybe I'm missing something, but I don't think it quite helps. I followed the link to the example page at: http://haskell.galois.com/cgi-bin/haskell-prime/trac.cgi/browser/HaskellPrime/Exception.hs Down towards the bottom, there is a definition of ArithException, and an example where it is used to throw Control.Exception.DivideByZero. But here's my concern. Let's say that I wanted to, for some reason, create a MultiplyByZero exception. It should be broadly considered an ArithException, and any code that catches an ArithException should be able to catch my MultiplyByZero exception. But the ArithException type is limited to storing errors that are defined by Control.Exception.ArithException. My MultiplyByZero is not defined there, so I am out of luck. The best I could do is define a new MultiplyByZero, and catch it in my own code. But any code that others have written to catch ArithExceptions would be blind to MultiplyByZero. -- John _______________________________________________ Haskell-prime mailing list Haskell-prime@haskell.org http://haskell.org/mailman/listinfo/haskell-prime