Luca, to use Control.Parallel, you need to download and install two packages, deepseq and parallel, from hackage.haskell.org. Most likely this will work with cabal, or you just download the two tarballs . The reason is, when packaging "parallel", this package has been removed from the GHC core libraries. BTW I am unsure whether this is at all clever, since it needs specific GHC support (at least for now - am I right here?) In addition, be informed that Control.Parallel.Strategies has been heavily restructured just last month (splitting it into deepseq and parallel is one of the changes, but not the most fundamental). If you want to try examples from GpH publications, you will certainly have some problems. parallel-1.x versions containing the original definitions are on hackage as well and should work for experiments. Cheers Jost Berthold PS: Loading Control.Parallel into ghci is a handy debugging procedure for the sequential parts of your program without any hassle, but if you do not compile and link your program, it will not use any parallelism (and run slow anyway).

From: Luca Ciciriello Subject: RE: ANNOUNCE: GHC version 6.12.1 To: , Message-ID: Content-Type: text/plain; charset="iso-8859-1"

Installed 6.12.1 on MacOS X 10.6Now I'm unable to load in GHCi of that modules containing "import Control.Parallel"I'm missing something? Luca

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From: marco-oweber@gmx.de To: glasgow-haskell-users@haskell.org Date: Mon, 14 Dec 2009 15:24:48 +0100 Subject: RE: ANNOUNCE: GHC version 6.12.1

Excerpts from Luca Ciciriello's message of Mon Dec 14 15:12:45 +0100 2009:

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I've the 6.10.4 version installed on my MacOS X 10.6 OS. Have I to uninstall this version of GHC before installing the Mac .pkg for the 6.12.1?

Hi Luca,

You should be able to get some hints by looking at where ghc is installed.

By default ghc puts its libraries into directory which contains the ghc release name. So libs can be installed at the same time. There are also ghc(i)-pkg-$GHC_VERSION executables. So it should be possible. However I don't know about Mac details.

But maybe someone else can give you a more accurate answer.

Sincerly Marc Weber