nominolo at googlemail.com
Tue Oct 7 10:25:50 EDT 2008
2008/10/7 Johannes Waldmann <waldmann at imn.htwk-leipzig.de>:
> with 6.10, the following does not typecheck:
> foo `Control.Exception.catch` \ _ -> return bar
> Ambiguous type variable `e' in the constraint:
> `Control.Exception.Exception e'
catch \(e :: SomeException) -> ...
This requires language ScopedTypeVariables (and perhaps PatternSignatures).
Of cause, you should try to be more specific about which exceptions
you want to catch as e.g., Ctrl-C and many other things are also
reported as exceptions.
> It is probably bad programming style anyway but what is the workaround?
> I found some references (in list emails) to catchAny, ignoreExceptions
> but these don't seem to have made it?
> Best regards, J.W.
> Glasgow-haskell-users mailing list
> Glasgow-haskell-users at haskell.org
More information about the Glasgow-haskell-users