Better is this:
data MalformedAddressException = MalformedAddressException String deriving (Show, Typeable)
throwDynIO x = throwIO (DynException $ toDyn x) You are right. Anyway the DynException will not be needed in the future because you can
On Wed, Sep 17, 2008 at 09:54:13PM -0700, Ryan Ingram wrote: throw arbitrary types directly.. But if you change the code the type checker won't fail, you'll keep catching the old user error while the new dyn type is beeing thrown. That's the mess. The only thing to do is whenever you start using inet_addr implement an HUnit test to ensure it still throws a user exception.. That's the only reliable way to get notified if the behaviour changes.. But the strength of haskell is that we don't have to write tests for everything because the type checker will do most work for us.. Another solution would be telling the compiler that the exception beeing caught must be thrown within this thread... But that's not possible with the new SomeException either. So my result is that Exceptions should not be used here (?) or there should be an alternative function.. Is that feasable to have to functions so that you can choose? inet_addr_ThrowEx ? inet_addr_Maybe ? Java would have recignized if the exception type changes from user error to dyn type. Haskell can't :-( Marc Weber