News aggregator

[ANN] yocto-1.0.1

General haskell list - Mon, 02/10/2014 - 5:56am
Howdy, `yocto`, a minimal JSON parser & printer, is now feature complete, documented and tested: http://hackage.haskell.org/package/yocto-1.0.1 From the CHANGELOG: - Removed `Read` & `Show` instances in favor of `decode` & `encode`. - Added `QuickCheck`-based test suite. - Fixed decoding of numbers between -1 and 1. - Added error check for trailing (unparsed) input. Anyway, I hope you find it useful; the code lives here: https://github.com/ajg/yocto Alvaro http://alva.ro _______________________________________________ Haskell mailing list Haskell< at >haskell.org http://www.haskell.org/mailman/listinfo/haskell
Categories: Incoming News

Master's Thesis: Open areas of research in Haskell

haskell-cafe - Mon, 02/10/2014 - 4:50am
Hello all! Beginning in September, I'll begin my Master's program in Computer Science, and I'm completely set on doing my thesis in some form of functional programming and/or Haskell. I've seen the Internship opportunities and areas of research for GHC (https://ghc.haskell.org/trac/ghc/wiki/Internships) but they all seem to apply to Ph.D candidates. That said, are there open areas of research that I could look into, or more resources in Haskell that would be useful for a two-year program's research? I'm hoping to have a set thesis by the time I begin my Master's program, which is why I'm giving myself six months in advance. Any help would be highly appreciated! Regards _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe< at >haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Categories: Offsite Discussion

Oregon Programming Languages Summer School, 2014

General haskell list - Mon, 02/10/2014 - 4:11am
We are pleased to announce the preliminary program for the 13th annual Oregon Programming Languages Summer School (OPLSS) to be held June 16th to 28th, 2014 at the University of Oregon in Eugene. The registration deadline will be April 14th, 2014. This year's program is titled Types, Logic, Semantics, and Verification and features the following speakers: Andrew Appel -- Software Verification Princeton University Lars Birkedal -- Category Theory Aarhus University Derek Dreyer -- Modular Reasoning about Stateful Programs Max Planck Institute for Software Systems Robert Harper -- Type Theory Foundations Carnegie Mellon University Greg Morrisett -- Certified Programming and State Harvard University Ulf Norell -- Programming in Agda Chalmers University of Technology Brigitte Pientka -- Proof Theory Foundations McGill University Stephanie Weirich -- Designing Dependently-Typed Programming Languages University of Pennsylvania Steve Zdancewic -- Software Foundations in Coq University of Pennsylvania
Categories: Incoming News

RHEL/EPEL 5 ghc packages

glasgow-user - Mon, 02/10/2014 - 3:49am
Hi, I wanted to mention some newer ghc builds I have made for RHEL5. EPEL5 currently has ghc-6.12.3 in stable, but I have built ghc-7.0.4 which has been in EPEL5 testing now for over a month. The update also includes cabal-install. I am planning to push it to stable this month but I wanted to mention it first here as a heads-up. https://admin.fedoraproject.org/updates/FEDORA-EPEL-2013-12484/ghc-7.0.4-45.3.el5,cabal-install-0.10.2-6.1.el5 Please report any problems with this in bugzilla: https://bugzilla.redhat.com/enter_bug.cgi?product=Fedora%20EPEL&component=ghc Jens ps Additionally I have a new ghc-7.4.2 repo for EPEL5 (which should also work on RHEL6) and includes haskell-platform: http://repos.fedorapeople.org/repos/petersen/ghc-7.4.2/ which is a backport from Fedora 19. Please report any problems with this directly to me. pps Later this year I plan to backport ghc-7.4.2 officially to EPEL6. _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users
Categories: Offsite Discussion

Extra Generic Compose

Haskell on Reddit - Mon, 02/10/2014 - 1:55am

I notice that a lot of things get composed:

  • Functions
  • Actions in a Monad
  • Monads
  • Types (sum types)
  • Typeclasses

So I was wondering just how crazy a generic (as in works for all of the above) definition of a compose operator/function would be. I don't necessarily care if haskell can do it (though it would be cool to see how close we can get, my limited understanding is that lens is basically trying to do this.)

submitted by satsujinka
[link] [29 comments]
Categories: Incoming News

Mark Jason Dominus: The perfect machine

Planet Haskell - Sun, 02/09/2014 - 9:55pm

You sometimes hear people claim that there is no perfectly efficient machine, that every machine wastes some of its input energy in noise or friction.

However, there is a counterexample. An electric space heater is perfectly efficient. Its purpose is to heat the space around it, and 100% of the input energy is applied to this purpose. Even the electrical energy lost to resistance in the cord you use to plug it into the wall is converted to heat.

Wait, you say, the space heater does waste some of its energy. The coils heat up, and they emit not only heat, but also light, which is useless, being a dull orange color. Ah! But what happens when that light hits the wall? Most of it is absorbed, and heats up the wall. Some is reflected, and heats up a different wall instead.

Similarly, a small fraction of the energy is wasted in making a quiet humming noise—until the sound waves are absorbed by the objects in the room, heating them slightly.

Now it's true that some heat is lost when it's radiated from the outside of the walls and ceiling. But some is also lost whenever you open a window or a door, and you can't blame the space heater for your lousy insulation. It heated the room as much as possible under the circumstances.

So remember this when you hear someone complain that incandescent light bulbs are wasteful of energy. They're only wasteful in warm weather. In cold weather, they're free.

Categories: Offsite Blogs

Weekend Project: Generic-Maybe

Haskell on Reddit - Sun, 02/09/2014 - 8:34pm

http://hackage.haskell.org/package/generic-maybe-0.2.0.0/docs/Generics-Maybe.html

Thought I would give generalizing Data.Maybe a shot using GHC.Generics after this conversation https://twitter.com/HaskellTips/status/432337300920352769

Thoughts?

submitted by jfischoff
[link] [52 comments]
Categories: Incoming News

haskell-search.org | research tools for Haskell

haskell-cafe - Sun, 02/09/2014 - 7:46pm
Hello, I would like to introduce http://haskell-search.org/. The idea is to index the most common Haskell sites to facilitate research on Haskell. It is a version for testing. If you like it, I can leave it running. Regards
Categories: Offsite Discussion

Installing Ghc 7.8 - ghc-split missing

haskell-cafe - Sun, 02/09/2014 - 2:28pm
I've put together an experimental package of Ghc 7.8 for ArchLinux. It's pulling the sources from git (the branch ghc-7.8 from git.haskell.org) and it basically performs the following steps to build and install: ./sync-all -r git://git.haskell.org get -b ghc-7.8 ./boot ./configure --prefix=/usr make -j 5 make DESTDIR=<the packaging dir> install The build and install completes successfully, and some trivial tests work (compiling hello-world, playing a bit with ghci, that sort of thing). However, compiling mtl fails, with this message: Configuring mtl-2.1.2... Building mtl-2.1.2... Preprocessing library mtl-2.1.2... [ 1 of 21] Compiling Control.Monad.Writer.Class ( Control/Monad/Writer/Class.hs, dist/build/Control/Monad/Writer/Class.o ) ghc: could not execute: /usr/lib/ghc-7.8.0.20140204/ghc-split And indeed, ghc-split is not installed using `make install`. Is this a known bug? /M
Categories: Offsite Discussion

Package for regular expressions

haskell-cafe - Sun, 02/09/2014 - 1:14pm
Hi, everyone! Due to the recent discussions discussions about regex- packages on libraries< at > and cafe, as well as due to the unicode bug in darcs that Erik Kow and I have stumbled upon I wanted to ask the Haskell community the following: What is up with the regular expression packages? Which one is the go-to package? There are really a bunch of them around (regex-compat, regex-tdfa, regex-posicx, regex-compat-tdfa,, ..) and it's not obvious at all what is the difference between them and which one should I use. Any advice or comments are appreciated. Sincerely yours,
Categories: Offsite Discussion

okmij.org

del.icio.us/haskell - Sun, 02/09/2014 - 7:55am
Categories: Offsite Blogs

okmij.org

del.icio.us/haskell - Sun, 02/09/2014 - 7:55am
Categories: Offsite Blogs