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Haskell Platform 2010.1.0.0 Windows installer RC3
by Mikhail Glushenkov 30 Mar '10

30 Mar '10

Hi all, I've uploaded the third (and, hopefully, final) RC of the Haskell Platform 2010.1.0.0 Windows installer to http://code.haskell.org/~refold/HaskellPlatform-2010.1.0.0-setup.exe Unless someone finds serious bugs in this RC, it can be released unchanged. What's new in 2010.1.0.0-rc3: * Fixed a PATH issue that prevented alex and happy from working (reported by Krasimir Angelov) * $APPDATA/cabal/bin is now added to PATH (reported by Han Joosten) -- () ascii ribbon campaign - against html e-mail /\ www.asciiribbon.org - against proprietary attachments

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Bugs in SampleVar and an API proposal
by Bas van Dijk 30 Mar '10

30 Mar '10

Hello, I was browsing over the code of Control.Concurrent.SampleVar and noticed the same kind of bugs I also discovered yesterday in Data.Unique: * Throwing an asynchronous exception at the right time can make the state of a SampleVar inconsistent which can cause a dead-lock. * Numeric expressions are put in a MVar lazily which can cause a space leak. The attached patch bundle contains a patch that fixes them both. The bundle also contains another patch which changes the API of Control.Concurrent.SampleVar. So this patch has to go through the library submission procedure. I propose making SampleVar an abstract (new)type instead of a type synonym. Advantages: * Users can not "screw up" the internal state like they can do now. * We can define instances for SampleVars without using the TypeSynonymInstances language extension. (This is actually the reason I bumped into the type synonym nature of SampleVars. I'm making a small library that defines some classes and I couldn't make SampleVar instances for them) Disadvantages: * Potentially breaks existing code. However if it breaks your code you are probably touching the internals which you shouldn't do anyway. Discussion period: 1 week (Because I think this is a no-brainer) Note I didn't derive an instance for Typeable for the SampleVar newtype. This should be done, but I don't know the proper way (manually, LANGUAGE DeriveDataTypeable or INSTANCE_TYPEABLE1(SampleVar,sampleVarTc,"SampleVar") ?). regards, Bas

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Re: Haskell Platform 2010.1.0.0 Windows installer RC2
by Han Joosten 30 Mar '10

30 Mar '10

The new version is great! I really appreciate it. Thanks! However, I think that it would be nice if it would update the path to contain the cabal\bin directory, into which cabal will install all executables. Now the user has to do that manually. Is this possible? And is this the right place to do such requests? Han Joosten -- View this message in context: http://old.nabble.com/Haskell-Platform-2010.1.0.0-Windows-installer-RC2-tp2… Sent from the Haskell - Libraries mailing list archive at Nabble.com.

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Fwd: Haskell Platform 2010.1.0.0 Windows installer RC2
by Krasimir Angelov 30 Mar '10

30 Mar '10

I forgot to reply to haskell-platform(a)projects.haskell.org and libraries(a)haskell.org. ---------- Forwarded message ---------- From: Krasimir Angelov <kr.angelov(a)gmail.com> Date: Tue, Mar 30, 2010 at 8:43 AM Subject: Re: Haskell Platform 2010.1.0.0 Windows installer RC2 To: Mikhail Glushenkov <the.dead.shall.rise(a)gmail.com> The installation works fine but after that when I try to use Alex it fails with: alex.exe: C:\Program Files\Haskell Platform\2010.1.0.0\alex-2.3.2/AlexTemplate-ghc: openFile: does not exist (No such file or directory) It is the same for happy: happy.exe: C:\Program Files\Haskell Platform\2010.1.0.0\happy-1.18.4/HappyTemplate-arrays-coerce: openFile: does not exist (No such file or directory) On Sat, Mar 27, 2010 at 10:23 PM, Mikhail Glushenkov <the.dead.shall.rise(a)gmail.com> wrote: > Hi all, > > I've uploaded the second RC of the Haskell Platform 2010.1.0.0 > Windows installer to > > http://code.haskell.org/~refold/HaskellPlatform-2010.1.0.0-setup.exe > > Unless someone finds serious bugs in this RC, it can be released unchanged. > > What's new in 2010-1.0.0-rc2: > > * $INSTDIR/mingw/bin is now added to PATH (#114) > > * cabal-install version updated to 0.8.1 > > * regex-posix now works (thanks to Simon Marlow!) > > * WinGHCi version updated to 1.0.5 > > * Profiling versions of all libraries are now included (#87) > > -- > () ascii ribbon campaign - against html e-mail > /\ www.asciiribbon.org - against proprietary attachments > _______________________________________________ > Libraries mailing list > Libraries(a)haskell.org > http://www.haskell.org/mailman/listinfo/libraries >

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proposed change to transformers package
by Ross Paterson 29 Mar '10

29 Mar '10

I propose to rename some of the modules in the transformers package so that it no longer conflicts with the mtl package: Control.Monad.Identity renamed as Data.Functor.Identity Control.Monad.Trans split between Control.Monad.Trans.Class and Control.IO.Trans.Class Then Control.Monad.Identity and Control.Monad.Trans are added to monads-fd making it closer to mtl. Darcs repositories: http://code.haskell.org/~ross/transformers/ http://code.haskell.org/~ross/monads-fd/ Docs: http://code.haskell.org/~ross/transformers/dist/doc/html/transformers/ http://code.haskell.org/~ross/monads-fd/dist/doc/html/monads-fd/

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Bugfixes for withThread and runInUnboundThread
by Bas van Dijk 29 Mar '10

29 Mar '10

Hello, I discovered two similar bugs in Control.Concurrent: * In the function: 'runInUnboundThread' a thread is forked which first installs an exception handler before performing the given IO computation. However it should first block asynchronous exceptions before forking the thread to ensure that the exception handler is always installed. In the attached patch I use the 'blockedApply' function which also ensures that the forked IO computation has the same blocked state as its parent thread. * There's a similar problem in the internal withThread function (which AFAIKS is only called in threadWaitRead). withThead also forgets to properly block asynchronous exceptions before forking a thread which needs to install an exception handler. In this case I didn't use blockedApply but only used block because withThread is only called with 'waitFd' which only performs an FFI call which can't receive asynchronous exceptions anyway. Should I make a bugreport or can this be applied immediately? regards, Bas

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Compiling regex-posix on Windows
by Mikhail Glushenkov 29 Mar '10

29 Mar '10

Hi all, The only problem stalling the release of the Windows installer for the new Haskell Platform is the bug in regex-posix. It compiles fine (using the libregex.a library from MinGW), but fails at runtime with the following error: Prelude> import Text.Regex.Posix Prelude Text.Regex.Posix> "bar" =~ "(foo|bar)" ::Bool Loading package array-0.3.0.0 ... linking ... done. Loading package bytestring-0.9.1.5 ... linking ... done. Loading package containers-0.3.0.0 ... linking ... done. Loading package mtl-1.1.0.2 ... linking ... done. Loading package regex-base-0.93.1 ... linking ... done. Loading package regex-posix-0.94.1 ... linking ... <interactive>: E:\Program Fil es (x86)\Haskell\regex-posix-0.94.1\ghc-6.12.1\HSregex-posix-0.94.1.o: unknown s ymbol `_regerror' : unable to load package `regex-posix-0.94.1' Prelude Text.Regex.Posix> Unfortunately, Chris, the maintainer, doesn't have access to a Windows machine with GHC currently, and therefore can't help me. I'd appreciate any pointers on how to fix this. -- () ascii ribbon campaign - against html e-mail /\ www.asciiribbon.org - against proprietary attachments

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Asynchronous exceptions and laziness bugs in Control.Concurrent.QSem/QSemN
by Bas van Dijk 29 Mar '10

29 Mar '10

Hello, after discovering the bugs regarding asynchronous exceptions and laziness in Data.Unique and Control.Concurrent.SampleVar I became a bit suspicious about the other concurrency mechanisms. It looks like Control.Concurrent.Chan is safe because it uses modifyMVar_ internally which performs the necessary block. Control.Concurrent.QSem and QSemN are not alright however! They both suffer the same bugs: * Potential dead-lock due to not blocking asynchronous exceptions. * Potential space-leak because of lazily putting numeric expression in a MVar. The attached patch fixes these bugs. regards, Bas

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Agda fails to install
by Dominic Steinitz 29 Mar '10

29 Mar '10

I'm guessing if I install happy then haskell-src will install and the agda will install but I'm not clear why this doesn't happen automatically. Hmm even installing happy doesn't seem to improve things. Aha su-ing and then installing happy with the --global flag did the trick. But now I have the same problem with alex :-) Ok now everything builds. I thought cabal was supposed to relieve me of this sort of dependency chasing? Dominic. > cabal: Error: some packages failed to install: > Agda-2.2.6 depends on haskell-src-1.0.1.3 which failed to install. > haskell-src-1.0.1.3 failed during the building phase. The exception was: > ExitFailure 1

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change to base to remove obsolete todo
by Jason Dagit 26 Mar '10

26 Mar '10

Hello, This is my first library patch. It's probably a bit silly to follow the full process on such a simple patch, but it does give me a chance to practice the policy. http://hackage.haskell.org/trac/ghc/ticket/3939 Should there be a timescale field on the ticket for following this step of the process? Did I overlook it? "Tracking. Add a Trac ticket of type proposal for the appropriate library component, with a timescale for consideration (to focus the community's attention for a limited period), adding the patch file as an attachment." I'm thinking one week should be reasonable for such a simple change. Thanks, Jason

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