Re: [Haskell-cafe] Hackage checking maintainership of packages
Hi Cafe. I have thought that a more interesting metric might be to send the maintainer an email when their package stops building automatically on hackage. I think, this is must have feature for new hackage. If error was occured during build, send email to maintainer: Error occured while building your package name with GHC version. Build log: If you are to fix it in a week [month?], please send reply for this message. If answer was received, then do not send such notifications every time during specified period (say, a week or month). If after end of this period, package still could not be build, then send next notification, maybe with additional question: If you are to maintain this package, please send a reply for this message... With any scenario, build failed notifications is a must have feature. WBR, Ilya Portnov. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Hackage checking maintainership of packages
07.05.2013 14:21, Ivan Lazar Miljenovic пишет: On 7 May 2013 17:36, Ilya Portnovport...@iportnov.ru wrote: Hi Cafe. I have thought that a more interesting metric might be to send the maintainer an email when their package stops building automatically on hackage. I think, this is must have feature for new hackage. If error was occured during build, send email to maintainer: Except that there are various reasons a package won't build on Hackage: * Temporary glitch with another Haskell dependency (e.g. package Foo depends upon Bar-x.*; maintainer of Bar uploads a new point release of Bar that fails to build just before Foo's maintainer uploads the new version, thus the build server picks the buggy version of Bar and thus the new version of Foo fails to build). * Requires a foreign library that isn't installed on the Hackage build server. * OS-dependent. Anyway, if package does not build, only maintainer can know why and what to do with it. As for OS- and environment-dependent packages, it would be nice to let maintainer mark package as not buildable, so that hackage should not try to build it. WBR, Ilya Portnov. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Display an inferred type during compilation
В письме от 27 апреля 2013 18:55:16 пользователь Corentin Dupont написал:
Hi Cafe,can I ask the compiler to display the type of an inferred value during
compile
time?It would be great if I can output a string during compilation with the
type.A little
bit like running :type in GHCi, but without GHCi... Because running GHCi is
sometime
painful (I have to clean my code first).
I'm thinking of something like:
main :: IO ()main = do a - someCode displayTypeAtCompileTime a return ()
$ ghc -c test.hstest.hs:4:3: your type is: Foo
Thanks,Corentin
Hi.
What about TemplateHaskell? Smth like:
{-# LANGUAGE TemplateHaskell #-}
module DisplayType where
import Language.TH
displayTypeAtCompileTime :: Name - Q Exp
displayTypeAtComileTime name = do
reified - reify name
-- inspect reified structure, see TH haddock documentation
runIO $ putStrLn $ show theType
[| undefined |] -- you need to return some expression; since you are not
to use it's
value, it may be even undefined, it seems.
###
{-# LANGUAGE TemplateHaskell #-}
module Main where
import DisplayType
main = do
...
$displayTypeAtCompileTime 'a
...
WBR, Ilya Portnov.
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Re: [Haskell-cafe] monoid pair of monoids?
Hi. Christopher Howard писал 21.12.2012 14:27: instance (Monoid a, Monoid b, Monoid c, Monoid d) = Monoid (Socket4 a b c d) where mempty = Socket4 mempty mempty mempty mempty Socket4 a b c d `mappend` Socket4 w x y z = Socket4 (a `mappend` w) (b `mappend` x) (c `mappend` y) (d `mappend` z) data Socket 5 a b c d e... et cetera Seeing as the pattern here is so rigid and obvious, I was wondering: is it possible to abstract this even more? So I could, for instance, just specify that I want a Socket with 8 types, and poof, it would be there? Or is this as meta as we get? (I.e., without going to something like Template Haskell.) Something like data a ::: b = a ::: b infixl 5 ::: instance (Monoid a, Monoid b) = Monoid (a ::: b) where ... So, Monoid instance for, say, (a ::: b ::: c) == ((a ::: b) ::: c) will (should) be inferred automatically. WBR, Ilya Portnov ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Instead of Haskell running on the JVM is there a way for Haskell to call a JVM language ...
Hi all. JP Moresmau писал 20.11.2012 13:01: You may want to have a look at my little HJVM project on Github ( https://github.com/JPMoresmau/HJVM). Promise, I'll put in on Hackage some day. Basically it provides FFI wrappers and some c code to be able to start a JVM and call Java methods, etc from Haskell. Please take a look at http://hackage.haskell.org/package/hs-java also. It's an assembler/disassembler of Java bytecode and *.class files. Moreover, there is https://github.com/MateVM/MateVM — an (experimental) Java VM on Haskell :) So, if you are interested in haskell/java interop, maybe we could integrate our efforts. Best regards, Ilya Portnov. -- JP Moresmau http://jpmoresmau.blogspot.com/ On Tue, Nov 20, 2012 at 7:53 AM, Mathijs Kwik math...@bluescreen303.nlwrote: KC kc1...@gmail.com writes: Instead of Haskell running on the JVM is there a way for Haskell to call a JVM language (or generate bytecode) to access the Java class libraries when needed? I once did a small test to get this working. It's not that hard, but needs some work. It's fine for exposing a few functions though. Basically it's a 2-step process, eased by using a makefile or similar helper. You have to compile your haskell code into a shared object (.so on linux, .dll on windows), which includes the haskell runtime (rts). This library can be called from c. A small pitfall is that you first need to do a call to initialize the haskell runtime, and when you're done using it, close it. This is most easily just tied to your c/java program's main initialization functions. Java is able to load/use these shared libraries through JNI. Of course you lose your platform-independance, so if you want your java application to work on multiple platforms / OSses, you need to build shared objects for all of them. Last but not least: You have to export the haskell functions you want through FFI. Also, make sure they use raw data types such as CString, as that what C and java will give you and expect back. So basically you go Haskell FFI - C - Java JNI I'm sorry I cannot give you any links or code, because I'm in a bit of a hurry. But google and the ghc docs are your friend. Mathijs Or Is there a way for a JVM language or bytecode to call Haskell when needed? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Typed TemplateHaskell?
Hello Haskell world. One well-known missfeature of TemplateHaskell is it's «untypedness». I mean, that if you have say an expression (Exp or Q Exp), you do not know it's type (does it represent String or Int or whatever). And GHC does not know too. So, one could easily construct bad-typed expressions using TH, and GHC will complain only on generated code, not on TH code. Such a missfeature was a reasoned decision, because adding some typing into TH will add much complexity to compiler and to language. As far as can I see, using features of last GHC one could write typed TH library relatively easily, and saving backwards compatibility. For example, now we have Q monad and Exp type in template-haskell package. Let's imagine some new package, say typed-template-haskell, with new TQ monad and new polymorphic type Exp :: * - *. Using last GHC's features, one will easily write something like expr :: Exp String, which will mean that expr represents a string expression. And we will need a new function, say runTQ :: TQ a - Q a (or some more complicated type), which will turn TypedTemplateHaskell's constructs into plain TH. One question will be on quotations and antiquotations: they are implemented to work untyped TH constructs, how to implement compatibility with new typed TH? We could add some support of them to GHC... Or, maybe define a phantom type (say, Any), and some conversion functions, say untyped :: Language.Haskell.TH.Syntax.Exp - Language.Haskell.TH.Typed.Syntax.Exp Any. Main idea is: seems new GHC enables us to implement typed TH without modifying GHC itself, only by writing a library. Is it so? Any further thoughts? With best regards, Ilya Portnov. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Named captures in regex-pcre?
Hi haskell-cafe. Is there a way to get named captures from regex using regex-pcre (or maybe other PCRE-package)? For example, I want to write something like let result = ab 12 cd =~ ab (?Pnumber\d+) cd :: SomeCrypticType and then have namedCaptures result == [(number, 12)]. I do not see somewhat similar in regex-pcre documentation. It parses such regexs fine, and captures work, but i do not see way to get _named_ captures. WBR, Ilya Portnov. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] bindings for libvirt
24.01.2012 10:50, Michael Litchard writes: Ilya, Yes please. Examining your code would go a long way toward helping me with this project. Ok, I published my current code at gitorious: https://gitorious.org/libvirt-hs. Please feel free to contribute, or even use (it's quite uncomplete currently) :) Bug reports, suggestions and patches are also welcome. WBR, Ilya Portnov. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] bindings for libvirt
On 16 янв, 03:27, Michael Litchard mich...@schmong.org wrote: Due to the direction things are going at work, I have become interested in Haskell bindings forlibvirt. Noticed that this hasn't been done yet. I was wondering if this was due to lack of motivation, or if there were some difficult hurdles withlibvirtthat make the project cost-prohibitive. If it's the former, I don't see a problem proceeding with exploration. If it's the latter, I'd like to know what the hurdles are. Hello. For my current projects, i'd also like to have bindings to libvirt. I even started to write something for them, using c2hs. If someone is interested, i could put my current (very basic) code to, say, github… Seems there will no big problems, but libvirt API is not so small, so it'll take time to write full bindings. WBR, Ilya Portnov. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
