- jhc - Haskell.org

JHC exception implementation status
by Csaba Hruska 14 Jan '19

14 Jan '19

Hi, I did not find an explicit statement about the current status of the implementation of exceptions in JHC. I've looked the source code have some clue. To me it seems that - GRIN backend only supports fatal ioError. The catch function does nothing (probably) because any raise operation will halt the program anyway. - There is an experimental (and disabled) GHC backend which would map JHC catch/raise primps to the corresponding GHC primops. In short the GHC's async exception system is not implemented and JHC's current exception system can only halt the program. Are these assumptions correct? Regards, Csaba Hruska

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Fwd: JHC Haskell compiler split into reusable components
by Csaba Hruska 19 Dec '18

19 Dec '18

Hello, I've added stack and cabal build support for JHC. I also split it into components. What do you think? https://github.com/csabahruska/jhc-components Regards, Csaba Hruska

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ffi: context reduction, no instance for: Jhc.Class.Real.Fractional Jhc.Type.C.CDouble
by Nawal Husnoo 23 Sep '17

23 Sep '17

Hi, I can't get the FFI to work as advertised - any ideas? Thanks, Nawal. Tutorial from here: http://book.realworldhaskell.org/read/interfacing-with-c-the-ffi.html $ cat fore.hs {-# LANGUAGE ForeignFunctionInterface #-} import Prelude import Foreign import Foreign.C.Types foreign import ccall "math.h sin" c_sin :: CDouble -> CDouble fastsin :: Double -> Double fastsin x = realToFrac (c_sin (realToFrac x)) main = print (fastsin 0.5) $ jhc -phaskell2010 fore.hs -o bin/fore jhc -phaskell2010 fore.hs -o bin/fore jhc 0.8.2 (mydniquipepo-32) Finding Dependencies... Using Ho Cache: '/home/nawal/.jhc/cache' Main [fore.hs] Typechecking... [1 of 1] Main (......................jhc: user error ( What: failure Why: context reduction, no instance for: Jhc.Class.Real.Fractional Jhc.Type.C.CDouble Where: on line 12 in fore.hs in the explicitly typed Main.fastsin Main.1_x = Jhc.Num.realToFrac (Main.c_sin (Jhc.Num.realToFrac Main.1_x)) {- on line 12 -} Compilation of module: Main)

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withFile, withBinaryFile using 'bracket'
by Henning Thielemann 03 Jan '16

03 Jan '16

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JHC homepage offline?
by Erik Deijl 28 Sep '15

28 Sep '15

I want to work with JHC but the homepage at http://repetae.net/computer/jhc/ <http://repetae.net/computer/jhc/> seems te be offline, is there a mirror?

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Compiling bytestring in jhc
by Nawal Husnoo 16 Aug '15

16 Aug '15

Hi, I'm trying to compile bytestring using JHC, but I'm getting an error: Why: context reduction, no instance for: Jhc.Class.Ord.Eq (Jhc.ForeignPtr.ForeignPtr Jhc.Type.Word.Word8) Any ideas? jhc -V jhc 0.8.2 (mydniquipepo-32) compiled by ghc-7.8 on a x86_64 running darwin Thanks, Nawal. nawal ~/000_Level_1/095_haskell_2015/jhc/jhc-0.8.2-build$jhc --build-hl tmp/build/bytestring-0.9.2.0/bytestring.yaml -L- -L. -i- -itmp/build/bytestring-0.9.2.0 jhc --build-hl tmp/build/bytestring-0.9.2.0/bytestring.yaml -L- -L. -i- -itmp/build/bytestring-0.9.2.0 jhc 0.8.2 (mydniquipepo-32) Creating library from description file: "tmp/build/bytestring-0.9.2.0/bytestring.yaml" Reading: "tmp/build/bytestring-0.9.2.0/bytestring.yaml" Finding Dependencies... Using Ho Cache: '/Users/nawal/.jhc/cache' Data.ByteString [tmp/build/bytestring-0.9.2.0/Data/ByteString.hs] Data.ByteString.Internal [tmp/build/bytestring-0.9.2.0/Data/ByteString/Internal.hs] Data.ByteString.Unsafe [tmp/build/bytestring-0.9.2.0/Data/ByteString/Unsafe.hs] Data.ByteString.Char8 [tmp/build/bytestring-0.9.2.0/Data/ByteString/Char8.hs] Data.ByteString.Fusion [tmp/build/bytestring-0.9.2.0/Data/ByteString/Fusion.hs] Data.ByteString.Lazy [tmp/build/bytestring-0.9.2.0/Data/ByteString/Lazy.hs] Data.ByteString.Lazy.Internal [tmp/build/bytestring-0.9.2.0/Data/ByteString/Lazy/Internal.hs] Data.ByteString.Lazy.Char8 [tmp/build/bytestring-0.9.2.0/Data/ByteString/Lazy/Char8.hs] Typechecking... [1 of 8] Data.ByteString.Internal(.............................................) [2 of 8] Data.ByteString.Unsafe(.............................................) [3 of 8] Data.ByteString (.........................jhc: user error ( What: failure Why: context reduction, no instance for: Jhc.Class.Ord.Eq (Jhc.ForeignPtr.ForeignPtr Jhc.Type.Word.Word8) Where: on line 333 in tmp/build/bytestring-0.9.2.0/Data/ByteString.hs in the explicitly typed Data.ByteString.eq ‹Data.ByteString.1_a(a)(Data.ByteString.Internal.PS Data.ByteString.2_p Data.ByteString.3_s Data.ByteString.4_l)› ‹Data.ByteString.5_b(a)(Data.ByteString.Internal.PS Data.ByteString.6_p' Data.ByteString.7_s' Data.ByteString.8_l')› | (Jhc.Class.Ord./=) Data.ByteString.4_l Data.ByteString.8_l' = Jhc.Prim.Prim.False | (Jhc.Order.&&) ((Jhc.Class.Ord.==) Data.ByteString.2_p Data.ByteString.6_p') ((Jhc.Class.Ord.==) Data.ByteString.3_s Data.ByteString.7_s') = Jhc.Prim.Prim.True | Jhc.Order.otherwise = (Jhc.Class.Ord.==) (Data.ByteString.compareBytes Data.ByteString.1_a Data.ByteString.5_b) Jhc.Prim.Prim.EQ {- on line 333 -} Compilation of module: Data.ByteString) nawal ~/000_Level_1/095_haskell_2015/jhc/jhc-0.8.2-build$ -- The best way to predict the future is to invent it. - Alan Kay http://www.husnoo.com/ -- The best way to predict the future is to invent it. - Alan Kay http://www.husnoo.com/

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github mirror
by James Crayne 25 Jul '15

25 Jul '15

This may have already existed, but I have been keeping a local git mirror of the darcs repository, and I decided to go ahead and publish it to github. So if anyone prefers to use git instead of darcs, by all means you are welcome to use my mirror. If you want to contribute new code, please keep it in a separate branch, so I can keep master in sync with John's tree. Thanks, https://github.com/jimcrayne/jhc

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state of jhc
by Cody Goodman 01 Jul '15

01 Jul '15

I heard that ajhc code was merged with jhc and I'm guessing that was a very good thing :) Does this page still reflect the state of jhc: http://repetae.net/computer/jhc/jhc.shtml

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[ANNOUNCEMENT]Introducing scher, a symbolic testing library in the style of QuickCheck
by Mario Alvarez Picallo 13 Jun '15

13 Jun '15

Dear all, I'm very pleased to announce that scher, the framework I've been working on, has already reached the point where I feel I can present it to the public and ask for feedback. scher is a property-based testing framework for Haskell programs with a similar API as QuickCheck or SmallCheck - the main difference is, instead of random testing, it uses the Klee <http://klee.github.io/> engine to perform concolic testing <https://en.wikipedia.org/wiki/Concolic_testing>, a kind of SMT-enhanced testing which provides greater guarantees than random testing. If you want to get started with it, you will need: * LLVM (I use version 2.9, but you should be able to get 3.4 working with some effort) * Klee * The klee-uclibc <https://github.com/klee/klee-uclibc> library * my fork of the jhc compiler <http://github.com/m-alvarez/jhc>, which adds support for running code without a GC * The scher <http://github.com/m-alvarez/scher> library * The scher-run <http://github.com/m-alvarez/scher-run> program, which will take care of feeding Klee the right input and formatting the output in a human-readable format. If anyone shows interest, I can write a quick-and-dirty tutorial of the exact list of the incantations you need to get started. As it is right now, everything is experimental and may be subject to change. Furthermore, everything and anything may be broken. Feel free to report any issues, bugs or simply feature requests on GitHub. Any feedback is enormously helpful to me. Happy verifying! -- Now I do not know whether I was then a lambda expression emulating a Turing machine, or whether I am a Turing machine emulating a lambda expression.

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Re: [jhc] "case fell off" for trivial program
by Travis Athougies 19 May '15

19 May '15

disclaimer: I found this e-mail thread through the jhc archives while I was not subscribed to jhc@ because I was having the same problems as Mario and Herbert. I subscribed afterwards, so I could join in on the discussion. I'm not sure how this will affect the mailing list's thread handling. I am having the same problem with JHC, and like Mario says, it's due to a pre-mature optimization. Basically, when JHC encounters a type where only one constructor has arguments, it erroneously thinks that it can store it as untagged. This is true only for types with two constructors, but not for types with more than two. I have the feeling this was written as a quick way to optimize list storage without realizing that the optimization would break types with more than two constructors. The optimization works for types with two constructors because JHC specifically handles the case of scrutinizing a two-constructor type when it generates C. Anyway, this can be fixed by disabling this optimization for types with more than two constructors. Change the line tyRep k tyty | Just xs <- tySiblings tyty, all triv [ x | x <- xs, x /= k] = Just TyRepUntagged where to tyRep k tyty | Just xs <- tySiblings tyty, length xs < 3 && all triv [ x | x <- xs, x /= k] = Just TyRepUntagged where Any ideas on how to get this bug changed in the official version? Travis

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