RE: Fail: thread killed
Marcin 'Qrczak' Kowalczyk wrote: [snip] Since the very purpose of killThread is to kill the damn thread, I find it inconvenient to have to wrap any thread which is supposed to be killable with Exception.catch to avoid the message. Worse: it should use block and unblock, otherwise there is a small window where killing the thread will still display the message. [snip] I agree with this. I also find it mildly irritating having to catch exceptions to stop GHC informing me that it's just garbage collected a thread which is permanently deadlocked. Ok, so which exceptions should be displayed? - Marcin says all async exceptions should be suppressed in child threads. - George says BlockedOnDeadMVar messages should also be suppressed (presumably only on child threads). any others? I'm not sure I agree that StackOverflow/HeapOverflow messages should be suppressed. It might be really confusing if your program just deadlocks instead of completing, when what actually happened was one of the child threads got a stack overflow and died silently. I can see the point about ThreadKilled though. There's only one way to kill a thread, and that's with killThread, so you don't want to see a message saying the thread was killed (except that the presence of the message indicates that the thread was alive before it was killed ;-). Cheers, Simon ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Re: Fail: thread killed
Marcin 'Qrczak' Kowalczyk wrote: [snip] Since the very purpose of killThread is to kill the damn thread, I find it inconvenient to have to wrap any thread which is supposed to be killable with Exception.catch to avoid the message. Worse: it should use block and unblock, otherwise there is a small window where killing the thread will still display the message. [snip] I agree with this. I also find it mildly irritating having to catch exceptions to stop GHC informing me that it's just garbage collected a thread which is permanently deadlocked. ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Fail: thread killed
I think I have raised the issue some time ago, but don't remember
why it hasn't been solved as I would like to.
Currently a thread which is killed displays Fail: thread killed,
e.g. in the following program:
import Concurrent
main:: IO ()
main = do
t - forkIO (threadDelay 100)
threadDelay 50
killThread t
threadDelay 50
Since the very purpose of killThread is to kill the damn thread,
I find it inconvenient to have to wrap any thread which is supposed
to be killable with Exception.catch to avoid the message. Worse:
it should use block and unblock, otherwise there is a small window
where killing the thread will still display the message.
I can probably agree that other kinds of exceptions are displayed;
maybe the programmer didn't know that exceptions are being thrown and
wants the diagnostic. It implies that any well-written code should
catch exceptions in all threads it creates (unless he is sure that the
code will not throw exceptions), since there shouldn't be compiler's
error output from a correct program. Not nice but I can live with that.
Should asynchronous exceptions be really displayed in threads other
than the main thread? IMHO not.
--
__(" Marcin Kowalczyk * [EMAIL PROTECTED] http://qrczak.ids.net.pl/
\__/
^^ SYGNATURA ZASTPCZA
QRCZAK
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