Re: [haskell art] New release Csound-expression 4.9 is out

As usual the library is available on Hackage: http://hackage.haskell.org/package/csound-expression The github repo is at https://github.com/spell-music/csound-expression Other useful libraries that go with csound-expression are csound-sampler, and csound-catalog: - csound-sampler

[haskell art] New release Csound-expression 4.9 is out

*The 4.9.0 is out! New features:* csound-expression - Functions for creation of FM-synthesizers. We can create the whole graph of FM-units (with feedback). Check out the module Csound.Air.Fm - Support for Monosynth patches. See atMono in the module Csound.Air.Patch see the

Re: [haskell art] the library of beautiful instruments implemented in haskell / csound

Alas there is no CsdSco typeclass anymore. The original idea was to implement score type with the most basic type and give the user a chance to write converters and use score playing functionality by the class CsdSco. But I've noticed that this approach was preventing me from using advanced score

Re: [haskell art] the library of beautiful instruments implemented in haskell / csound

Hi The most useful part of this (for me) is the ability to play midi-style instruments at arbitrary frequencies, so this looks great! To that end, I'm looking for the definition of the 'CsdSco' typeclass, as I want to write my own instance. It seems to be referenced in the csound-expression

Re: [haskell art] [Haskell-cafe] the library of beautiful instruments implemented in haskell / csound

Oh interesting! I had thought CSound didn't do realtime synthesis. tom El Sep 14, 2015, a las 6:15, Anton Kholomiov escribió: > It's all was played live with Csound triggered by midi keyboard and recorded > with Audacity (connected to csound output with Jack) > >

Re: [haskell art] [Haskell-cafe] the library of beautiful instruments implemented in haskell / csound

Yes, it can work in real time! There is even an Android app that uses Csound in real-time. It's called EtherPad. And a couple of iOS apps: csGrain and csSpectral http://www.youtube.com/watch?v=SZ7Tbc8dIsg http://www.boulangerlabs.com/ Though some instruments require lots of CPU. With Jack I

Re: [haskell art] [Haskell-cafe] the library of beautiful instruments implemented in haskell / csound

Thanks for feedback. I've used several sources on sound design: Ian McCurdy collection of csound instruments: http://iainmccurdy.org/csound.html Thor demystified series by Gordon Reid: https://www.propellerheads.se/substance/discovering-reason/index.cfm?article=part19=get_article Csound pieces

Re: [haskell art] [Haskell-cafe] the library of beautiful instruments implemented in haskell / csound

It's all was played live with Csound triggered by midi keyboard and recorded with Audacity (connected to csound output with Jack) 2015-09-14 13:11 GMT+03:00 Anton Kholomiov : > Thanks for feedback. I've used several sources on sound design: > > Ian McCurdy collection

[haskell art] the library of beautiful instruments implemented in haskell / csound

Status update for my haskell synth csound-expression. The main point is presence of many cool instruments. They are implemented in the package csound-catalog. All packages are compiled with GHC-7.10 So the hackage fails to build them and unfortunately docs a broken too. But you can look at the

Re: [haskell art] [Haskell-cafe] the library of beautiful instruments implemented in haskell / csound

These sound great, congratulations! "Batteries included" is a great place to be. Can you point to references you used to create the instrument definitions? Tom On Sun, Sep 13, 2015 at 9:13 AM, Anton Kholomiov wrote: > Status update for my haskell synth

[haskell art] 3rd CFP FARM 2015 -- final reminder

3rd CFP FARM 2015 3rd ACM SIGPLAN International Workshop on Functional Art, Music, Modelling and Design Vancouver, Canada, 5 September, 2015 affiliated with

Re: [haskell art] Music made with Haskell

Thanks for the kind words. It was a long road to making the tracks 2014-12-01 4:34 GMT+03:00 Francesco Ariis fa...@ariis.it: ― Attachment links are at the end of this email ― On Fri, Nov 28, 2014 at 12:47:48PM +0400, Anton Kholomiov wrote: I wrote two tracks completely with Haskell. You

[haskell art] [Announce] Music Suite v1.8

I am happy to announce the release of Music Suite version 1.8. This release in short: Cleaner API for dealing with Voices, Notes and time structures in general. New equal-temperament pitch representation. Improved handling of diatonic vs. chromatic transposition in the Common pitch

Re: [haskell art] Music made with Haskell

― Attachment links are at the end of this email ― On Fri, Nov 28, 2014 at 12:47:48PM +0400, Anton Kholomiov wrote: I wrote two tracks completely with Haskell. You can listen to them on the soundcloud: I finally listened to them, enjoyed the pieces very much, especially the soothing Ocean. The

Re: [haskell art] Music made with Haskell

On Fri, Nov 28, 2014 at 12:47:48PM +0400, Anton Kholomiov wrote: I wrote two tracks completely with Haskell. You can listen to them on the soundcloud: I downloaded the zip'd source, but I cannot listen to your track on soundcloud (it requires Flash, and Linux doesn't play well with Flash). Is

Re: [haskell art] Music made with Haskell

You can listen in the ghci! ghci :l Celtic.hs main It relies on csound-sampler. Which can be installed from Hackage with cabal: cabal install csound-sampler And the csound should be installed. See csounds.com 2014-11-29 17:09 GMT+04:00 Francesco Ariis fa...@ariis.it: On Fri, Nov 28, 2014

[haskell art] Music made with Haskell

I wrote two tracks completely with Haskell. You can listen to them on the soundcloud: https://soundcloud.com/anton-kho/celtic https://soundcloud.com/anton-kho/invisible-ocean The music is based on samples but a single track uses no more than 6 samples. The code is under 100 lines of code. I'm

[haskell art] haskell in several upcoming live performances in the UK

Hello everyone. I hope the Haskell Cafe will tolerate this musical interruption. I suppose it's not so often that you can hear two different performers use Haskell in their performances in one concert, but if you live in the UK you have several opportunities to do so in the next few days. Both

[Haskell-cafe] No upgrade of GHC version in Ubuntu repository

Hi Caffe, deb packages of GHC (and Haskell Platform) in Ubuntu's (LTS Precise, 12.04) universe are not upgrading at all. GHC package is almost two years old, still on version 7.4.1, and GHC site still recommends to use Haskell Platform from repository. Even kernel is upgrading more often,

Re: [Haskell-cafe] Compiling arbitrary Haskell code

For those who are interested (and I already chatted with Chris on IRC), I've implemented a pastebin that is able to (among some other things) to run arbitrary Haskell code: http://paste.hskll.org/ I've also developed a 'restricted-workers' library for managing processes that should run in secured

Re: [Haskell-cafe] No upgrade of GHC version in Ubuntu repository

Hi vlatko, New versions of GHC are available in newer versions of Ubuntu (12.10, 13.04 etc.). I recommend you to download, build and install Haskell-platform from sources. Best regards, Danylo Lizanets  --- Original message --- From: Vlatko Basic vlatko.ba...@gmail.com Date: 14

Re: [Haskell-cafe] No upgrade of GHC version in Ubuntu repository

Hi Danylo, I have 7.6.3 already, but I was wondering why the repository packages are not maintained. 12.04 is an LTS for 5 years, so I suppose many would stick to it for a longer time. br, vlatko Original Message

Re: [Haskell-cafe] No upgrade of GHC version in Ubuntu repository

  Because LTS must be stable. Although you can add some PPA with new versions of packages to your software sources list. --- Original message --- From: Vlatko Basic vlatko.ba...@gmail.com Date: 14 October 2013, 13:28:21 Hi Danylo, I have 7.6.3 already, but I was wondering why the

Re: [Haskell-cafe] Stackage with GHC 7.8 has started

Hi, Am Sonntag, den 13.10.2013, 17:50 +0200 schrieb Michael Snoyman: I wanted to announce that FP Complete is now running a Jenkins job to build Stackage with GHC 7.8. You can see the current results in the relevant Github issue[1]. Essentially, we're still trying to get version bounds

Re: [Haskell-cafe] Stackage with GHC 7.8 has started

On Mon, Oct 14, 2013 at 3:42 PM, Joachim Breitner m...@joachim-breitner.dewrote: Hi, Am Sonntag, den 13.10.2013, 17:50 +0200 schrieb Michael Snoyman: I wanted to announce that FP Complete is now running a Jenkins job to build Stackage with GHC 7.8. You can see the current results in the

Re: [Haskell-cafe] No upgrade of GHC version in Ubuntu repository

Hi, On Mon, Oct 14, 2013 at 01:28:17PM +0200, Vlatko Basic wrote: I have 7.6.3 already, but I was wondering why the repository packages are not maintained. 12.04 is an LTS for 5 years, so I suppose many would stick to it for a longer time. I added PPAs for GHC 7.6.3 recently. Feel free to

Re: [Haskell-cafe] No upgrade of GHC version in Ubuntu repository

Looks like we're missing the point here. I did add the PPAs, and all is OK for me. :-) LTS is a stable release, and yet many other apps get updated regulary, but GHC does not. GHC is not part of the system itself, it's just an app, like many others are. So I

Re: [Haskell-cafe] No upgrade of GHC version in Ubuntu repository

Hi Simon, Thanks for that. I already have it on the list, and this one: ppa:fmarier/git-annex with many packages already precompiled. (if someone doesn't want cabal) br, vlatko Original Message Subject: Re: [Haskell-cafe] No upgrade of GHC version in Ubuntu repository

Re: [Haskell-cafe] Increasing memory use in stream computation

Hi Claude, On Thursday 10 October 2013 20:05:37 I wrote: Although, maybe I can do all the logic of the small function in the list monad, and stream the resulting list, as you do in the above. I tried a corresponding variant of my full program, but the memory use is quite a lot higher at the

Re: [Haskell-cafe] No upgrade of GHC version in Ubuntu repository

Hi, Am Montag, den 14.10.2013, 15:34 +0200 schrieb Vlatko Basic: Looks like we're missing the point here. I did add the PPAs, and all is OK for me. :-) LTS is a stable release, and yet many other apps get updated regulary, but GHC does not. GHC is not part of the system itself, it's just an

Re: [Haskell-cafe] Stackage with GHC 7.8 has started

Michael, I see one of my packages is on that list, because of the upper bound on template-haskell. I would love the raise the upper bound, but of course only if it will actually build. Can I download a binary version snapshot GHC 7.8 somewhere so I can test and apply changes accordingly? I

[Haskell-cafe] Xcode 5 support for GHC iOS

Hi all, Just wanted to let you know I've finished updating GHC iOS to support Xcode 5. The new scripts are at https://github.com/ghc-ios/ghc-ios-scripts/tree/xcode5 and you'll find updated instructions at http://ghc.haskell.org/trac/ghc/wiki/Building/CrossCompiling/iOS . Please let me know if

Re: [Haskell-cafe] Nested monadic monoids via Traversable?

If anyone is interested, Typeclassopedia pointed me to Composing Monads by Jones and Duponcheel (1993), which contains exactly my implementation along with some other nice patterns for composing Monads via Traversable.sequence (called swap in the paper) and related operators. It would be

[Haskell-cafe] Stackage with GHC 7.8 has started

Hi everyone, I wanted to announce that FP Complete is now running a Jenkins job to build Stackage with GHC 7.8. You can see the current results in the relevant Github issue[1]. Essentially, we're still trying to get version bounds updated so that a build can commence. I'd like to ask two things

Re: [Haskell-cafe] ordNub

Niklas Hambüchen mail at nh2.me writes: In sets, the order does not matter, while for nub it does. Let's be careful here!. Niklas, when you say order, do you mean: * the _ordering_ from the Ord instance? Or * the relative sequence of elements in the list? ... the fact that Set is used

Re: [Haskell-cafe] ordNub

On 13/10/13 21:42, AntC wrote: Niklas Hambüchen mail at nh2.me writes: In sets, the order does not matter, while for nub it does. Let's be careful here!. Niklas, when you say order, do you mean: * the _ordering_ from the Ord instance? Or * the relative sequence of elements in the list?

Re: [Haskell-cafe] ordNub

Niklas Hambüchen mail at nh2.me writes: On 13/10/13 21:42, AntC wrote: ... If you use the Set library, that fact may be very visible! Because Set re-sequences the whole list, as per its Ord instance. But List.nub preserves the list sequence (except for omitting duplicates). I

Re: [Haskell-cafe] ordNub

On 14/10/13 03:20, AntC wrote: Thanks Niklas, I hadn't spotted those benchmarks back in July. No worries :) I'm surprised at that result for singletons (and for very small numbers of elements which are in fact each different). I think one of the main reasons for the performance difference

Re: [Haskell-cafe] ordNub

Niklas Hambüchen mail at nh2.me writes: On 14/10/13 03:20, AntC wrote: ... Then here's a further possible optimisation, instead of making separate calls to `member` and `insert`: This I understand again. Where do you get insert' from? containers doesn't seem to have it. Do you

Re: [Haskell-cafe] typeclass to select a list element

Hello everyone, I'm still trying to resolve my problem. I try to restate it in a simpler way. Is it possible to write extract and update functions for L ? import Data.Nat data family X (n::Nat) :: * data L (n::Nat) where Q :: L (Succ n) - X n - L n E :: L n extract :: L Zero - X n

Re: [Haskell-cafe] typeclass to select a list element

Hi Paolino, There are some functions similar to that in HList (Data.HList.HArray). Check the repo http://code.haskell.org/HList for a version that uses more type families / gadts. Maybe there is a way to take advantage of the fact that you've labelled the elements of the list, but extract isn't

Re: [Haskell-cafe] ordNub

I would like to come back to the original question: How can ordNub be added to base? I guess we agree that Data.List is the right module for a function of type Ord a = [a] - [a], but this introduces * a cyclic dependency between Data.List and Data.Set * a base dependency on containers. What is

Re: [Haskell-cafe] ordNub

On Oct 12, 2013, at 2:47 PM, Niklas Hambüchen m...@nh2.me wrote: I would like to come back to the original question: How can ordNub be added to base? I guess we agree that Data.List is the right module for a function of type Ord a = [a] - [a], but this introduces * a cyclic

Re: [Haskell-cafe] ordNub

On 12/10/13 20:43, Anthony Cowley wrote: I think nub's behavior is rather set-related, so I don't really understand the objection to putting it in Data.Set. In sets, the order does not matter, while for nub it does. nub:: Eq a = [a] - [a] ordNub :: Ord a = [a] - [a] both do not

Re: [Haskell-cafe] ordNub

* Anthony Cowley acow...@seas.upenn.edu [2013-10-12 15:43:57-0400] On Oct 12, 2013, at 2:47 PM, Niklas Hambüchen m...@nh2.me wrote: I would like to come back to the original question: How can ordNub be added to base? I guess we agree that Data.List is the right module for a

[Haskell-cafe] Haskellers in Nashville,TN

Anyone here from the Nashville, TN area? t would be nice to meet regularly with others to discuss and work with Haskell. Also, this group is now available: www.meetup.com/The-Haskell-Study-Group/ If you want to participate remotely, that works too, I'm just looking for others to meet with

Re: [Haskell-cafe] typeclass to select a list element

Yes, it's possible, but it's rather painful. Here is my working attempt, written to be compatible with GHC 7.6.3. Better ones may be possible, but I'm doubtful. {-# LANGUAGE TemplateHaskell, RankNTypes, TypeFamilies, TypeOperators, DataKinds, ScopedTypeVariables, GADTs, PolyKinds

Re: [Haskell-cafe] Suppressing HLint on pattern match of files

Just add it next to -Wall wherever you‘re setting that, because I think you must be setting that yourself somewhere (it’s not on by default). On Thu, Oct 10, 2013 at 6:11 PM, Graham Berks gra...@fatlazycat.com wrote: Ah good point :) Wonder if I can change it on cabal file somehow. Thanks

[Haskell-cafe] MonadBaseControl IO instance for conduits ?

Hello Haskellers! Is it posible to create instance of MonadBaseControl IO (ConduitM i o m) ? This would give a great posibility to catch exceptions just inside the ConduitM monad with lifted-base package. And more, http-conduit's `withManager` restricts base monad (which must be base for

Re: [Haskell-cafe] Suppressing HLint on pattern match of files

You can also do this on a module basis with {-# OPTIONS -fno-warn-missing-signatures #-}. I prefer adding type signatures even for cases where I don't think it's important. GHC spits them out so almost no time spent, and someone might find it useful at some point. On Fri, Oct 11, 2013 at 5:53

Re: [Haskell-cafe] Store type-class polymorphic values generically

Wait... what do you mean Core cannot generate new names to be exported. I meant if I add a new name in the Core transformation, that doesn't change the module's export list as seen by everything outside that module. Which makes sense, it just means I have to change my approach. Maybe you mean

[Haskell-cafe] Compiling arbitrary Haskell code

Is there a definitive list of things in GHC that are unsafe to _compile_ if I were to take an arbitrary module and compile it? E.g. off the top of my head, things that might be dangerous: * TemplateHaskell/QuasiQuotes -- obviously * Are rules safe? * #includes — I presume there's some security

Re: [Haskell-cafe] Compiling arbitrary Haskell code

On Fri, Oct 11, 2013 at 1:30 PM, Christopher Done chrisd...@gmail.comwrote: Is there a definitive list of things in GHC that are unsafe to _compile_ if I were to take an arbitrary module and compile it? E.g. off the top of my head, things that might be dangerous: *

Re: [Haskell-cafe] Compiling arbitrary Haskell code

On 12.10.2013 00:30, Christopher Done wrote: Is there a definitive list of things in GHC that are unsafe to _compile_ if I were to take an arbitrary module and compile it? E.g. off the top of my head, things that might be dangerous: * TemplateHaskell/QuasiQuotes -- obviously * Are rules safe?

Re: [Haskell-cafe] Compiling arbitrary Haskell code

Whatever guarantees GHC offers (e.g. using Safe Haskell), I would always run things like these in a sandbox. It's much better for security to dissallow everything and then whitelist some things (e.g. let the sandbox communicate with the rest of the world in some limited way) than the other way

Re: [Haskell-cafe] Compiling arbitrary Haskell code

On 12 October 2013 01:19, Johan Tibell johan.tib...@gmail.com wrote: Whatever guarantees GHC offers (e.g. using Safe Haskell), I would always run things like these in a sandbox. It's much better for security to dissallow everything and then whitelist some things (e.g. let the sandbox

Re: [Haskell-cafe] MonadBaseControl IO instance for conduits ?

Aleksey Uymanov s9gf4...@gmail.com writes: Is it posible to create instance of MonadBaseControl IO (ConduitM i o m) ? No, it is not, for approximately the same reason that you cannot create one for ContT (or any form of continuation). -- John Wiegley FP Complete

[Haskell-cafe] Call to Action - Fay FFI Bindings for AngularJS

I've talked to a lot of people that would like to be able to use Fay with AngularJS, this seems like a great idea! I don't use AngularJS personally, but I would be happy to help out with designing it and making code reviews. Has anyone started working on this already, and do you have any

Re: [Haskell-cafe] hdbc-odbc not getting any data using mssql stored procedure

Hello Grant, pulling this topic out of the archive as I face similar issue and found a work around. I'm unsure what's happening in gp_somestoredproc but if using the sql management studio, you see some output such as (X row(s) affected) then you might want to put set nocount on before issuing

[Haskell-cafe] Increasing memory use in stream computation

(Sorry for the long email.) Summary: why does the attached program have non-constant memory use? Introduction I've written a program to do a big computation. Unfortunately, the computation takes a very long time (expectedly), and the memory use increases slowly (unexpectedly),

Re: [Haskell-cafe] Suppressing HLint on pattern match of files

Is that actually from HLint though? I think that comes from GHC with -Walland can be disabled with -fno-warn-missing-signatures. On Thu, Oct 10, 2013 at 7:50 AM, Graham Berks gra...@fatlazycat.com wrote: Hi, would like to disable 'Top-level binding with no type signature' In my test modules

Re: [Haskell-cafe] hdbc-odbc not getting any data using mssql stored procedure

Hi Gauthier, that answer was perfect! I just tried it out and It completely solved my problem. Thanks so much! Grant. On Thu, Oct 10, 2013 at 8:58 AM, Gauthier Segay gauthier.se...@gmail.comwrote: Hello Grant, pulling this topic out of the archive as I face similar issue and found a work

Re: [Haskell-cafe] Increasing memory use in stream computation

Hi Arie, On 10/10/13 14:02, Arie Peterson wrote: (Sorry for the long email.) Summary: why does the attached program have non-constant memory use? Looking at the heap profile graph (generated with +RTS -h, no need to compile with profiling) I see the increasing memory use is split about

Re: [Haskell-cafe] Suppressing HLint on pattern match of files

Ah good point :) Wonder if I can change it on cabal file somehow. Thanks On 10 October 2013 at 14:05:45, Dag Odenhall (dag.odenh...@gmail.com) wrote: Is that actually from HLint though? I think that comes from GHC with -Wall and can be disabled with -fno-warn-missing-signatures. On

[Haskell-cafe] Nested monadic monoids via Traversable?

I have been experimenting with compositions of monads carrying associated monoids (i.e. Writer-style) and discovered the following pattern: -- {-# LANGUAGE DeriveFunctor, DeriveFoldable, DeriveTraversable,

Re: [Haskell-cafe] Increasing memory use in stream computation

Arie Peterson wrote: (Sorry for the long email.) Summary: why does the attached program have non-constant memory use? Unfortunately, I don't know. I'll intersperse some remarks and propose an alternative to stream fusion at the end, which allows your test program to run in constant space.

Re: [Haskell-cafe] Increasing memory use in stream computation

Hi Claude, Looking at the heap profile graph (generated with +RTS -h, no need to compile with profiling) I see the increasing memory use is split about evenly between STACK and BLACKHOLE. I don't know what that means or why it occurs, but replacing `small` solved that problem for me:

Re: [Haskell-cafe] Increasing memory use in stream computation

Hi Bertram, Unfortunately, I don't know. I'll intersperse some remarks and propose an alternative to stream fusion at the end, which allows your test program to run in constant space. A quicker way to spot the increased memory usage is to look at GC statistics. I used ./Test +RTS

Re: [Haskell-cafe] Using Quick Check generators for getting arbitrary value streams

Luke Evans l...@eversosoft.com writes: I was hoping I could use Arbitrary instances to generate streams of values for test data. It looks like you're not 'supposed' to be trying this, other than for the specific purpose of then testing some properties on these streams within Quick Check

[Haskell-cafe] Conditional lens

Hello! I am working with TypeReps, and while writing some functions I have noticed that I could use lenses to simplify them; however, I have stumbled upon some difficulties. First I’ll try to clarify which functions I want to write: * a function for converting TypeRep of, say, `Maybe x` to

Re: [Haskell-cafe] Conditional lens

`ifL` isn't a legal lens for several reasons. Lens s t a b generally requires that the types a subsumes b and b subsumes a, and that s subsumes t and t subsumes s. Lens s (Maybe t) (Maybe a) b is a huge red flag. There is an 'illegal prism' provided by lens that is a more principled version of

Re: [Haskell-cafe] Interfacing real-time stocks data API

I did not find such a library, but I am interested in Haskell trading automation too. BTW, I am developing package for testing trading systems, it can just download historical data from some free russian stock services for now. https://github.com/s9gf4ult/hadan If you interested we could join

Re: [Haskell-cafe] Interfacing real-time stocks data API

Yes, the trading system, or code generator. It depends on what would be easier to implement. But firstly I need a simulator and history data crawler what I am working on. 2013/10/9 Miro Karpis miroslav.kar...@gmail.com Hi Alexey, thank you for response. You wrote that you are developing

[Haskell-cafe] FP relates events in NYC

Hi folks, I will be visiting New York at the end of the October and I would like to catch some cool Haskell events if possible. I'll be staying in the city from 29th of October to the 10th of November and I would like to plan my trip ahead. I am looking for anything nerdy: talks, seminars,

Re: [Haskell-cafe] Interfacing real-time stocks data API

I would love to see Haskell bindings for this: https://us.etrade.com/active-trading/api On Tue, Oct 8, 2013 at 1:26 PM, Miro Karpis miroslav.kar...@gmail.comwrote: Please, did/does anybody tried to interface with Haskell some real-time stocks data API? If yes, please which one? So far I came

Re: [Haskell-cafe] Interfacing real-time stocks data API

Yes, I also like that one. Problem is that they give access only to US citizens and some limited countries. m. -Original Message- From: David Fox d...@seereason.com To: miroslav.kar...@gmail.com Cc: Haskell Cafe haskell-cafe@haskell.org Sent: Wed, 09 Oct 2013 18:54 Subject: Re:

Re: [Haskell-cafe] Interfacing real-time stocks data API

There is also Interactive Brokers API, which used to be a lower cost alternative. On Wed, Oct 9, 2013 at 1:57 PM, miroslav.kar...@gmail.com wrote: Yes, I also like that one. Problem is that they give access only to US citizens and some limited countries. m. -Original Message-

[Haskell-cafe] Fwd: [Haskell-beginners] RankNTypes + ConstraintKinds to use Either as a union

(from thread: http://www.haskell.org/pipermail/beginners/2013-October/012703.html) Why type inference can't resolve this code? {-# LANGUAGE RankNTypes, ConstraintKinds #-} bar :: (Num a, Num b) = (forall c. Num c = c - c) - Either a b - Either a b bar f (Left a) = Left (f a) bar f (Right b)

[Haskell-cafe] Case studies, step two

I want to thank everyone who provided pointers for the last question about this. They were a big help. We're now trying to narrow things down a bit. If you have either converted part of a business project from a language like ruby or python to Haskell, or have a business project that integrates

Re: [Haskell-cafe] Interfacing real-time stocks data API

IB is not real-time though. On Wed, Oct 9, 2013 at 12:48 PM, Yuri de Wit yde...@gmail.com wrote: There is also Interactive Brokers API, which used to be a lower cost alternative. On Wed, Oct 9, 2013 at 1:57 PM, miroslav.kar...@gmail.com wrote: Yes, I also like that one. Problem is that

[Haskell-cafe] RankNTypes + ConstraintKinds to use Either as a union

Thiago Negri wrote: Why type inference can't resolve this code? {-# LANGUAGE RankNTypes, ConstraintKinds #-} bar :: (Num a, Num b) = (forall c. Num c = c - c) -Either a b -Either a b bar f (Left a) = Left (f a) bar f (Right b) = Right (f b) bar' = bar (+ 2) -- This compiles ok foo ::

[Haskell-cafe] Suppressing HLint on pattern match of files

Hi, would like to disable 'Top-level binding with no type signature' In my test modules that are prefixed with Test. Is this possible ?? Thanks ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org

Re: [Haskell-cafe] ANN: E-book version of the Typeclassopedia

Thanks, I wanted this for a long time as well! A. On 5 October 2013 17:25, Flavio Villanustre fvillanus...@gmail.com wrote: Very useful, thanks! On Oct 4, 2013 9:13 AM, Erlend Hamberg ehamb...@gmail.com wrote: While re-reading Brent Yorgey's Excellent Typeclassopedia I converted it to

[Haskell-cafe] Interfacing real-time stocks data API

Please, did/does anybody tried to interface with Haskell some real-time stocks data API? If yes, please which one? So far I came down to ActveTick,... thanks, m. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org

[Haskell-cafe] ANN: hsqml-0.2.0.0

Dear All, I would like to announce version 0.2.0.0 of the HsQML graphics library. HsQML provides a Haskell binding to the Qt Quick framework. It allows you to write graphical applications where the front-end is written in Qt Quick's QML language (incorporating JavaScript) and the back-end is

Re: [Haskell-cafe] Using Quick Check generators for getting arbitrary value streams

Hi Luke, It seems like you missed this module: http://hackage.haskell.org/package/QuickCheck-2.6/docs/Test-QuickCheck-Gen.html Adam On Mon, Oct 7, 2013 at 7:21 PM, Luke Evans l...@eversosoft.com wrote: I was hoping I could use Arbitrary instances to generate streams of values for test data.

[Haskell-cafe] Lenses that work with Arrows

Dear all, I introduce a very simple extension to the Lens datatype from Control.Lens that allows it to work with Arrows: https://gist.github.com/tomjaguarpaw/6865080 I would particularly like to discuss this with authors of Control.Lens to see if such an idea is suitable for inclusion in

Re: [Haskell-cafe] A question regarding reading CPP definitions from a C header

If you use cpphs as a library, there is an API called runCpphsReturningSymTab. Thence you can throw away the actual pre-preprocessed result text, keep only the symbol table, and lookup whatever macros you wish to find their values. I suggest you make this into a little code-generator, to

[Haskell-cafe] typeclass to select a list element

Hello, I'm trying to use a type class to select an element from a list. I would like to have a String CC as a value for l10'. {-# LANGUAGE MultiParamTypeClasses, GADTs,FlexibleInstances, DataKinds ,TypeFamilies, KindSignatures, FlexibleContexts, OverlappingInstances, StandaloneDeriving,

Re: [Haskell-cafe] Lifting IO actions into Applicatives

Isn't it the case that there could be more than one natural transformation between functors? On Tue, Oct 1, 2013 at 10:00 PM, John Wiegley jo...@fpcomplete.com wrote: Yitzchak Gale g...@sefer.org writes: In fact, it even makes sense to define it as FunctorIO, with the only laws being

Re: [Haskell-cafe] Lifting IO actions into Applicatives

On Mon, Oct 07, 2013 at 07:57:23PM +0400, Daniil Frumin wrote: Isn't it the case that there could be more than one natural transformation between functors? Definitely. In addition rwbarton responded to my challenge by finding two different applicative morphisms between the same applicative,

Re: [Haskell-cafe] Lifting IO actions into Applicatives

Daniil Frumin difru...@gmail.com writes: Isn't it the case that there could be more than one natural transformation between functors? Yes, I imagine there would have to be some newtype wrappers to distinguish in those cases. -- John Wiegley FP Complete Haskell tools,

Re: [Haskell-cafe] Lenses that work with Arrows

On Mon, 7 Oct 2013 10:40:13 +0100, Tom Ellis tom-lists-haskell-cafe-2...@jaguarpaw.co.uk wrote: Dear all, I introduce a very simple extension to the Lens datatype from Control.Lens that allows it to work with Arrows: https://gist.github.com/tomjaguarpaw/6865080 I would particularly

Re: [Haskell-cafe] Lenses that work with Arrows

On Mon, Oct 07, 2013 at 07:14:44PM +0200, Niklas Haas wrote: On Mon, 7 Oct 2013 10:40:13 +0100, Tom Ellis tom-lists-haskell-cafe-2...@jaguarpaw.co.uk wrote: I introduce a very simple extension to the Lens datatype from Control.Lens that allows it to work with Arrows:

Re: [Haskell-cafe] Lenses that work with Arrows

On Mon, Oct 07, 2013 at 06:22:33PM +0100, Tom Ellis wrote: On Mon, Oct 07, 2013 at 07:14:44PM +0200, Niklas Haas wrote: On Mon, 7 Oct 2013 10:40:13 +0100, Tom Ellis tom-lists-haskell-cafe-2...@jaguarpaw.co.uk wrote: I introduce a very simple extension to the Lens datatype from

Re: [Haskell-cafe] A question regarding reading CPP definitions from a C header

Thanks for your answer, looks like this is my only option to do this. Can you provide some information about what does parameters of runCpphsReturningSymTab stands for? I made several attempts but couldn't get any useful return value. For example, I have no idea what does third parameter does.

Re: [Haskell-cafe] A question regarding reading CPP definitions from a C header

Have you looked into using hsc2hs? If I understand your problem, it's designed exactly to solve it. -- Carl On Mon, Oct 7, 2013 at 12:20 PM, Ömer Sinan Ağacan omeraga...@gmail.comwrote: Thanks for your answer, looks like this is my only option to do this. Can you provide some information

[Haskell-cafe] Using Quick Check generators for getting arbitrary value streams

I was hoping I could use Arbitrary instances to generate streams of values for test data. It looks like you're not 'supposed' to be trying this, other than for the specific purpose of then testing some properties on these streams within Quick Check itself. I'm looking for something like the

Re: [Haskell-cafe] A question regarding reading CPP definitions from a C header

Carl, thank you very much. This is exactly what I was looking for, and it solved my problem in 5 minutes. What's awesome is that when Cabal finds a .hsc file it automatically calls this tool. Great. Thanks again. --- Ömer Sinan Ağacan http://osa1.net 2013/10/8 Carl Howells

[Haskell-cafe] POSA

Hi all, Michael Snoyman, Andreas Voellmy and I are invited to write an article about Warp to The Performance of Open Source Applications: http://aosabook.org/en/index.html It is now open to the public including our article. http://aosabook.org/en/posa/warp.html Enjoy! --Kazu

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