- Glasgow-haskell-users

An attempt at foldr/build fusion for zip
by Matt Harden 23 Apr '01

23 Apr '01

Hi, I think I may have found a way to get zip & friends to fuse with *both* of their input lists. I am not a heavy ghc hacker, though, so I may be missing something important that makes this unworkable. I have no idea what kind of code this would actually end up creating. Anyway, here's my attempt; it ties in with the current foldr2 scheme. I eagerly any await comments or questions, especially from the foldr/build gurus. -- foldr2_both.lhs: Attempting to fuse zip with both input lists. We seem to be forced to use a recursive datatype to accomplish this. We're using newtype, so there should be no overhead from construction/deconstruction of this type, right? \begin{code} newtype BuildZip a b = BZ ((a -> (BuildZip a b) -> b) -> b) bz :: (forall b. (a->b->b)->b->b) -> b -> BuildZip a b bz f n = f (\x xs -> BZ (\c -> c x xs)) (BZ (\_ -> n)) {-# INLINE bz #-} foldr2_both :: (a->b->c->c) -> BuildZip a c -> BuildZip b c -> c foldr2_both k (BZ xs) (BZ ys) = xs (\x xs' -> ys (\y ys' -> k x y (foldr2_both k xs' ys') ) ) {-# RULES "foldr2/both" forall k n (f::forall z.(a->z->z)->z->z) (g::forall z.(b->z->z)->z->z) . foldr2 k n (build f) (build g) = foldr2_both k (bz f n) (bz g n) #-} \end{code} -- END foldr2_both.lhs Best regards, Matt Harden

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RE: The (Interactive) Glasgow Haskell Compiler -- version 5.00
by Simon Marlow 23 Apr '01

23 Apr '01

> Mon, 16 Apr 2001 00:15:39 +1000, Manuel M. T. Chakravarty > <chak(a)cse.unsw.edu.au> pisze: > > > The source tar ball misses the configure scripts (it has the > > `configure.in's, but the source tar ball should be > > autoconf'ed, shouldn't it?) > > BTW, IMHO 'make maintainer-clean' should not delete configure scripts > (comments say that it doesn't, but it does). I dunno. 'make distclean' leaves the configure scripts in place, 'make maintainer-clean' is supposed to get you back to a pristine tree as it would be if it were just checked out from CVS. Cheers, Simon

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RE: Stack trace on error (and packages)
by Simon Marlow 23 Apr '01

23 Apr '01

> Also, less importantly, how do I generate packages? I have a bunch of > .o files (modules) all compiled using -package-name and -c, > but I can't > find the correct ghc flag to link them into a library (.a/Linux). You use the usual 'ar' tool for making a .a library, something like: $ ar cru libfoo.a a.o b.o c.o To make this into a package, see the section on packages in the user's guide: http://www.haskell.org/ghc/docs/5.00/set/packages.html Cheers, Simon

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New InstallShield: Free At Last
by Reuben Thomas 23 Apr '01

23 Apr '01

I've uploaded a new InstallShield for GHC 4.08.2 for Windows which includes *all* the programs required to use and even rebuild GHC from source [GHC developers should note that it doesn't include everything needed to build from CVS; see the most recent 5.00 docs in CVS for details]. This means that there's no longer any need to install Cygwin. Since GHC needs bash to work, and building it requires mv, rm and cp, plus many other basic utilities, you get a reasonably nice minimal command-line environment anyway; I've added ls to the mix for extra comfort. Although the InstallShield is now 20M, overall there's far less to download, and now GHC should break far less often. Another implication of this development is that the Windows version of 5.00 should now happen sooner rather than later. One caveat: the installation instructions on haskell.org are now somewhat out of date. I'll try to correct that soonish. -- http://sc3d.org/rrt/ | Si hoc legere scis nimium eruditionis habes.

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GHC 5.0 - InstallShield for Windows?
by Christian Lescher 20 Apr '01

20 Apr '01

When do you expect an InstallShield version of GHC 5.0 for Windows? Christian

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no problem with .sgml
by S.D.Mechveliani 20 Apr '01

20 Apr '01

I wrote recently | I want to install GHC-5.00 (from binaries, on Linux). | But the installation guide, as most documentation, is in the .sgml | format. I can read ASCII, .dvi, .ps, .tex, html texts. | But what to do with .sgml, please? Forget this question, please. Because I un-archivated the binaries and found there the needed docs on ghc in the needed formats. ----------------- Serge Mechveliani mechvel(a)botik.ru

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RE: sgml
by Julian Seward (Intl Vendor) 20 Apr '01

20 Apr '01

The documentation should be supplied in .html and .ps files, at least in the .tar.bz2 binary build I did, and, I presume in the RedHat 6.2/7.0 RPMs. Are you saying this is not the case? J | -----Original Message----- | From: S.D.Mechveliani [mailto:mechvel@math.botik.ru] | Sent: Tuesday, April 17, 2001 1:08 PM | To: glasgow-haskell-users(a)haskell.org | Subject: sgml | | | Hello, | | I want to install GHC-5.00 (from binaries, on Linux). | But the installation guide, as most documentation, is in the .sgml | format. I can read ASCII, .dvi, .ps, .tex, html texts. | But what to do with .sgml, please? | | ----------------- | Serge Mechveliani | mechvel(a)botik.ru | | _______________________________________________ | Glasgow-haskell-users mailing list | Glasgow-haskell-users(a)haskell.org | http://www.haskell.org/mailman/listinfo/glasgow-haskell-users |

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RE: The (Interactive) Glasgow Haskell Compiler -- version 5.00
by Julian Seward (Intl Vendor) 20 Apr '01

20 Apr '01

Thanks, Tom & Manuel. I've put them on the web page. | There are now also x86 RPMS for RedHat Linux 6.2 at | | | ftp://ftp.cse.unsw.edu.au/pub/users/chak/jibunmaki/i386-rh6.2/ | ghc-5.00-2.i386.rpm | | ftp://ftp.cse.unsw.edu.au/pub/users/chak/jibunmaki/i386-rh6.2/ | ghc-prof-5.00-2.i386.rpm | | This build has been kindly contributed by Tom Moertel. | | Manuel |

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how to implement timeouts for IO operations?
by Johannes Waldmann 19 Apr '01

19 Apr '01

what is the Right Way to impose a timeout condition on IO actions? the GHC manual says ( http://www.haskell.org/ghc/docs/5.00/set/select.html ) "use threadDelay and asynchronous exceptions". When I do this: timed :: Int -> IO a -> IO a timed d action = do let timer = do threadDelay d throw $ AssertionFailed "timer expired" t <- forkIO timer x <- action killThread t return x it seems to work, but how do I turn off the "Fail: thread killed" messages? -- -- Johannes Waldmann ---- http://www.informatik.uni-leipzig.de/~joe/ -- -- joe(a)informatik.uni-leipzig.de -- phone/fax (+49) 341 9732 204/252 --

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Where can I get "Main.dll_o" and "PrelMain.dll_o"?
by andreas.siglreithmayr＠sdm-research.de 19 Apr '01

19 Apr '01

I run ghc under cygwin WinNT. If I compile a simple HelloWorld program as described in the instalation descripton, I get the following error: $ ghc -o main main.hs gcc: D:/Unix/ghc/lib/Main.dll_o: No such file or directory gcc: D:/Unix/ghc/lib/PrelMain.dll_o: No such file or directory Do you know whats wrong? Or where can I get the files? -- Andreas Siglreithmayr mailto:Andreas.Siglreithmayr@sdm-research.de sd&m Research GmbH http://www.sdm.de Thomas-Dehler-Str. 18 , D-81737 Muenchen, Germany Tel +49 89 63812-917 Fax -150

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