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fgl-5.5.0.1

libraries list - Mon, 02/16/2015 - 3:22pm
Hi Ivan, could you make a new release of fgl that works with ghc-7.10? I could compile it locally after the following changes: Data/Graph/Inductive/Query/Monad.hs +import Control.Applicative +import Control.Monad (ap, liftM) +instance Monad m => Functor (GT m g) where + fmap = liftM + +instance Monad m => Applicative (GT m g) where + pure = return + (<*>) = ap Data/Graph/Inductive/Monad/IOArray.hs -{-# LANGUAGE MultiParamTypeClasses, FlexibleInstances #-} +{-# LANGUAGE MultiParamTypeClasses, FlexibleInstances, FlexibleContexts #-} I'm not sure why FlexibleContexts is now needed and I'm not sure how the package version number should change. Cheers Christian
Categories: Offsite Discussion

Reminder: The GHC 7.10 Foldable/Traversable Survey ends on the 21st February!

Haskell on Reddit - Mon, 02/16/2015 - 2:04pm

Previously, on /r/haskell: GHC 7.10 Prelude: we need your opinion.

Since the previous thread is already on page ~3, I thought a reminder might be reasonable.

Links submitted by lserit7fc56v9o24
[link] [comment]
Categories: Incoming News

Venerable Haskell Platform, necessity or product of a bygone era?

Haskell on Reddit - Mon, 02/16/2015 - 12:51pm

Given the present state of the Haskell build arena (stackage, LTS, improved cabal, sandbox, etc.) I have some questions for the community.

1) Is Haskell Platform a necessity anymore?

2) Who is best served by Haskell Platform?

3) What is Haskell Platform's future?

submitted by noZone
[link] [57 comments]
Categories: Incoming News

Functional Jobs: Engineering Manager (OCaml or Haskell under Linux) at FireEye (Full-time)

Planet Haskell - Mon, 02/16/2015 - 11:29am

Position Title: Engineering Manager

Location: Dresden, Germany

The Company

FireEye has invented a purpose-built, virtual machine-based security platform that provides real-time threat protection to enterprises and governments worldwide against the next generation of cyber attacks. These highly sophisticated cyber attacks easily circumvent traditional signature-based defenses, such as next-generation firewalls, IPS, anti-virus, and gateways. The FireEye Threat Prevention Platform provides real-time, dynamic threat protection without the use of signatures to protect an organization across the primary threat vectors and across the different stages of an attack life cycle. The core of the FireEye platform is a virtual execution engine, complemented by dynamic threat intelligence, to identify and block cyber attacks in real time. FireEye has over 3,100 customers across 67 countries, including over 200 of the Fortune 500.

Job Description:

In Dresden, Germany, an outstanding team of formal methods engineers uses formal methods tools, such as proof assistants, to develop correctness proofs for FireEye's leading edge products. In real world applications of formal methods tools, automation is often not sufficient for the specific problems at hand. Therefore, we are seeking outstanding software developers with a passion for implementing both well-designed as well as ad-hoc formal methods software tools for proof refactoring, proof search, systematic testing and other areas.

Responsibilities:

  • Design and development of software tools, scripts and automated processes for various tasks, supporting formal method tools
  • Refactoring, redesigning and rewriting earlier ad-hoc solutions in a systematic way
  • Maintaining existing tools and scripts
  • Continuous focus and contribution in the areas of performance, reliability, scalability, and maintainability of the product
  • Active participation in our ongoing process enhancements in software development and verification practices

Desired Skills & Experience

  • BS or MS in Computer Science or equivalent experience
  • Strong programming skills in OCaml or Haskell under Linux
  • Good skills in scripting languages, such as bash, perl or python
  • Good knowledge of logic and formal logical reasoning
  • Experience with parallel programs running on multiple machines and cores
  • Interest in acquiring basic knowledge about proof assistants for higher-order logic
  • Excellent interpersonal and teamwork skills
  • Strong problem solving, troubleshooting and analysis skills
  • Excellent oral and written communication skills

Get information on how to apply for this position.

Categories: Offsite Blogs

Measuring runtime?

Haskell on Reddit - Mon, 02/16/2015 - 9:53am

First of all, sorry if the english is not that clear, it's not my first language. Hey guys, I'm pretty new to haskell and so far I love it! I got a couple of easy classes that I'm using my algorithm analysis class to practice a little Haskell and it's working out fine. The issue i'm having now is I don't know how to time my programs runtime. Just have to measure the time it takes for mergesort, insertionsort and selectionsort to get the answer for x items.

How can I get that value in HS?

submitted by Gran-Tizoc
[link] [7 comments]
Categories: Incoming News

Cancelled: Re: Typed TH

haskell-cafe - Mon, 02/16/2015 - 7:24am
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Categories: Offsite Discussion

Événement annulé: Re: Typed TH - Lun. 16 Févr. 2015 09:00 - 10:00 (gautier.difolco< at >gmail.com)

haskell-cafe - Mon, 02/16/2015 - 7:21am
Cet événement a été annulé et supprimé de votre agenda. Titre : Re: [Haskell-cafe] Typed TH Date : Lun. 16 Févr. 2015 09:00 - 10:00 Paris Agenda : gautier.difolco< at >gmail.com Participants : * Gautier DI FOLCO- organisateur * haskell-cafe * ben.franksen< at >online.de Invitation de Google Agenda : https://www.google.com/calendar/ Vous recevez ce message à l'adresse haskell-cafe< at >haskell.org, car vous participez à cet événement. Pour ne plus recevoir de notifications pour cet événement à l'avenir, refusez cet événement. Vous avez également la possibilité de créer un compte Google sur la page https://www.google.com/calendar/ et de définir vous-même les paramètres de notification pour l'intégralité de votre agenda. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe< at >haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
Categories: Offsite Discussion

Invitation: Re: Typed TH - Lun. 16 Févr. 2015 09:00 - 10:00 (Gautier DI FOLCO)

haskell-cafe - Mon, 02/16/2015 - 7:20am
Vous avez été invité à l'événement suivant. Titre : Re: [Haskell-cafe] Typed TH Date : Lun. 16 Févr. 2015 09:00 - 10:00 Paris Agenda : Gautier DI FOLCO Participants : * Gautier DI FOLCO- organisateur * haskell-cafe * ben.franksen< at >online.de Détails de l'événement : https://www.google.com/calendar/event?action=VIEW&eid=XzcxaTNhZTFtY2RqM2diYjI2a3NtNGI5aDY1aWo4YjlvY29wbTZiYjVjaGhqMnA5bmNoajNjZWI2Y2cgaGFza2VsbC1jYWZlQGhhc2tlbGwub3Jn&tok=MjUjZ2F1dGllci5kaWZvbGNvQGdtYWlsLmNvbWZmNjMxZmZmZjdjNDAwNDc2NDRmMjE3NDRkZGIzNGY0ZTEyNTFjNmE&ctz=Europe/Paris&hl=fr Invitation de Google Agenda : https://www.google.com/calendar/ Vous recevez ce message à l'adresse haskell-cafe< at >haskell.org, car vous participez à cet événement. Pour ne plus recevoir de notifications pour cet événement à l'avenir, refusez cet événement. Vous avez également la possibilité de créer un compte Google sur la page https://www.google.com/calendar/ et de définir vous-même les paramèt
Categories: Offsite Discussion

Build box compromised?

Haskell on Reddit - Mon, 02/16/2015 - 5:13am
Categories: Incoming News

Why doesn't Cabal...

Haskell on Reddit - Mon, 02/16/2015 - 5:06am

For each package, create a list of all the other packages it imports, the functions, types etc. that it imports from those packages, and their types. Also a list of all the functions etc. the package itself exports, and their types.

Then, if package foo exports function qux with type int -> bool, and package bar imports foo.qux, expecting it to have type int -> IO bool, running cabal install foo bar fails with an error "the function qux defined in package foo doesn't match that expected by package bar". As opposed to downloading both, compiling foo, beginning to compile bar, then failing with a type error.

submitted by logicchains
[link] [9 comments]
Categories: Incoming News

gloss-examples install fails

haskell-cafe - Mon, 02/16/2015 - 12:28am
I installed gloss, and then the binary for llvm (http://llvm.org/builds/ ) But still gloss-examples fail, because it requires gloss-raster, which fails (below). I see some discussion of this from last year (https://mail.haskell.org/pipermail/haskell-cafe/2014-March/113001.html), Do I need to do some path manipulations to get this to work? I see llc & opt as mentioned in that note installed under mingw, but not under the llvm installed site. ------------------------------------------------------------------------ <C:\Windows\System32>cabal install gloss-raster Resolving dependencies... Configuring gloss-raster-1.9.2.1... Building gloss-raster-1.9.2.1... Failed to install gloss-raster-1.9.2.1 Build log ( C:\Users\guthrie\AppData\Roaming\cabal\logs\gloss-raster-1.9.2.1.log ): Building gloss-raster-1.9.2.1... Preprocessing library gloss-raster-1.9.2.1... [1 of 2] Compiling Graphics.Gloss.Raster.Array ( Graphics\Gloss\Raster\Array.hs, dist\build\Graphics\Gloss\Raster\Array.o ) <no location info>: Warning:
Categories: Offsite Discussion

Refactor unqualified imports to qualified onesautomatically?

haskell-cafe - Sun, 02/15/2015 - 9:55pm
Hi, In a previous post regarding overlapping images in wx [1], Stephen Tetley suggested I study Blobs [2]. I want to find its wx logic, but as it stands I can't distinguish the wx commands from the others, because wx is too large a library for me to know all the names in it, and Blobs imports most of its modules unqualified. Is there some automatic way of changing an unqualified import to a qualified import, so that every function from the module of interest would be prefixed to indicate where it comes from? If not, is there some other way around the problem? Thanks, Jeff [1] https://mail.haskell.org/pipermail/haskell-cafe/2015-January/117669.html [2] https://hackage.haskell.org/package/Blobs-0.3/src/ _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe< at >haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
Categories: Offsite Discussion

cabal install wxcore problem

Haskell on Reddit - Sun, 02/15/2015 - 9:11pm

When I try to install wxcore in a sandbox I get this error http://lpaste.net/115319 Can someone help me?

submitted by nocte_aeterna
[link] [1 comment]
Categories: Incoming News

Folk techniques for debugging Haskell?

Haskell on Reddit - Sun, 02/15/2015 - 7:42pm

I've been coding in Haskell for about 4 years now, and I'm realizing that perhaps I've fallen into a rut with the way I debug my programs. After hoping and failing to learn better methods I eventually fell into a pattern of just importing a library of self rolled trace functions.

In an effort to grow and maybe code faster, I'm hoping to start a discussion here about how you actually debug your programs.

The most common functions I use are:

-- m stands for message, x is the value, f is a utility function -- tr is like trace but includes the value of what's being evaluated tr m x = trace (m++":"++show x) x trWith f m x = trace (m++":"++show (f x)) x -- tc shows a trace before and after the value is evaluated -- helpful for tracking down infinite recursion. tc m x = trace (m++"-->") $ trace ("-->"++m++" "++(show x)) x tcWith f m x = trace (m ++"-->") $ trace ("-->"++m++" "++show (f x)) x

I have some others that work inside specific monads and etc. I've even gone so far as to colorize certain data structure traversals using the System.Console.ANSI module.

I find that the deeper the program logic is inside abstractions the more difficult and befuddling it can be to debug.

I'm curious about what methods folks use to hunt and prevent bugs on a daily basis?

submitted by biglambda
[link] [56 comments]
Categories: Incoming News

New Haskell.org

Haskell on Reddit - Sun, 02/15/2015 - 4:20pm
Categories: Incoming News