ghci, -O
I fear there is certain misunderstanding about -O usage with ghc-5.00 interactive. Simon Marlow and User's Guide (Section 4.4) say that -O does not work with ghci. For technical reason, the bytecode compiler doesn't interact well with one of the optimization passes [..] What is a bytecode compiler? The one that prepares a lightly compiled code for the interpreter? What I meant is something like this: to compile ghc -c -O Foo.hs in the batch mode and then run ghci ... Preude :load Foo ... Foo sm [1..000] I tried this with certain small function Foo.sm, and it works, and runs better than when compied with -Onot. Now, as I see that ghci can load and run the code made by -O, I wonder what the User's Guide means by saying -O does not work with GHCi. Maybe ghci -O ? could be meaningful? - Serge Mechveliani [EMAIL PROTECTED] ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
catchAllIO
Dear all, I keep getting problems with expections. In the example catchAllIO ( action ) $ \ any - return foo is it guaranteed that *no* exception that is raised in `action' propagates to the outside? (This is with ghc-4.08. Should I upgrade? Well, I will upgrade sometime anyway, but would it help with respect to this problem?) Regards, -- -- Johannes Waldmann http://www.informatik.uni-leipzig.de/~joe/ -- -- [EMAIL PROTECTED] -- phone/fax (+49) 341 9732 204/252 -- ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Exceptions and sockets
OK now I upgraded to ghc-5.00 but the situation didn't change. My suspicion is that it's not the fault of `catch'. I think what happens is this: I `Socket.accept' a connection and get a handle. Now, if the connections dies, but I still write to the handle, the whole thing crashes - without throwing an exception. (I checked that the RTS thinks `hIsWritable h' even if `h' does no longer exist in reality.) How could I work around this? SocketPrim? -- -- Johannes Waldmann http://www.informatik.uni-leipzig.de/~joe/ -- -- [EMAIL PROTECTED] -- phone/fax (+49) 341 9732 204/252 -- ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Re: Exceptions and sockets
In local.glasgow-haskell-users, you wrote: I `Socket.accept' a connection and get a handle. Now, if the connections dies, but I still write to the handle, the whole thing crashes - without throwing an exception. (I checked that the RTS thinks `hIsWritable h' even if `h' does no longer exist in reality.) Looks to me like you're forgetting that the OS will give you a sigPIPE on (semi-)closed sockets, which translates to a segfault unless you install a signal handler: - http://www.haskell.org/ghc/docs/latest/set/socket.html#AEN13989 - socket(2) -- Abstrakte Syntaxträume. Volker Stolz * [EMAIL PROTECTED] * PGP + S/MIME ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
RE: ghci, -O
Now, as I see that ghci can load and run the code made by -O, I wonder what the User's Guide means by saying -O does not work with GHCi. Maybe ghci -O ? could be meaningful? ghci -O is exactly the combination that doesn't work. Cheers, Simon ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Re: GHC and the Lazy Functional State Threads Paper
So you can fix it for example by using a specialized version of freezeArr inside accumArray, of type (Ix i, IArray a e) = STArray s i e - ST s (a i e) This will give quite general type of accumArray: arbitrary immutable array from the IArray class. freezeArr2:: (Ix i, IArray.IArray a e) = STArray s i e - ST s (a i e) freezeArr2 = MArray.freeze If the immutable array type used was particularly UArray, it would be more efficient to use the corresponding STUArray instead of STArray, so freezing could just copy a memory block (there are magic specializations in ghc's libraries for such case). But if the element type was to remain generic, the type would have to be constrained over STUArray freezeArr3:: (Ix i, MArray.MArray (MArray.STUArray s) e (ST s), IArray.IArray a e) = (MArray.STUArray s i e) - ST s (a i e) freezeArr3 = MArray.freeze Is this the way to do it? I wonder a bit if this triggers the optimization if 'a' is of type STUArray. (By the way I still have problems to see where unboxed values are a good thing and were you should better avoid them.) In addition I wonder why there are so many array types. Are both STArray and IOArray really necessary and what's the difference between them? What about DiffArray? I'm still surprised by operations like 'unsafeFreezeArray' and 'freezeArray'. Shouldn't the garbage collector juge if there are still other references to a distinct object? Regards, Thomas ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
