On Fri, 18 Jul 2008, Brandon S. Allbery KF8NH wrote:
On 2008 Jul 18, at 11:05, Ian Lynagh wrote:
On Thu, Jul 17, 2008 at 09:16:36AM -0400, Isaac Dupree wrote:
I'm not entirely happy with this particular sketch of a proposal, but do people think that my initial issue is something to be concerned about at all? (I'd be glad to be disproved :-)
It's hard to say if it'll be a problem in practice - we don't have any experience with writing exception hierarchies.
I'm going to ask a possibly silly question: has anyone thought about this vis-a-vis Simon's proposal of a new signals API? It's not that unusual for signals (usually SIGUSR1/SIGUSR2, often SIGINT, SIGHUP, sometimes SIGABRT, SIGQUIT) to be used as asynchronous triggers --- which might be best represented in the "Haskell world" as special exceptions. Likewise, it often makes sense to treat SIGPIPE, SIGHUP, SIGINT as exceptions instead of signals.
I have seen this solution in Modula-3 (like exception ThreadAlerted), but I'm not happy with it, since the occurence of a signal is not specific to the IO action you call (like CouldNotOpenFile to 'open'). I would use a separate mechanism for signal handling.