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APLAS 2014: Last CFP

General haskell list - Wed, 05/07/2014 - 4:10am
=============================================================== APLAS 2014 12th Asian Symposium on Programming Languages and Systems http://www.math.nagoya-u.ac.jp/~garrigue/APLAS2014/ 17-19 November 2014, Singapore CALL FOR PAPERS Abstracts due May 26 (full paper by June 2) =============================================================== ================ INVITED SPEAKERS ================ Zhenjiang Hu (NII, Japan) Dexter Kozen (Cornell University, USA) Julien Verlaguet (Facebook, USA) ========== BACKGROUND ========== APLAS aims to stimulate programming language research by providing a forum for the presentation of latest results and the exchange of ideas in programming languages and systems. APLAS is based in Asia, but is an international forum that serves the worldwide programming language community. APLAS is sponsored by the Asian Association for Foundation of Software (AAFS) founded by Asian researchers in cooperation with many researchers from Europe and the USA. Past APLAS symposium
Categories: Incoming News

SMTP Mail server

Haskell on Reddit - Wed, 05/07/2014 - 3:32am

Is there an existing library for an SMTP mail server? I would create an SMTP server using the library to process mail messages in a custom format. But I can't use an existing mail server program like postfix because every incoming mail needs to be processed by a seperate thread and based on the format of the received mail I need to do certain things. I searched all over but couldn't find a lightweight SMTP server library although I found a few SMTP server programs similar to postfix which is not what I need.

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

Splicious is now accepting applications for alphauser trials

haskell-cafe - Wed, 05/07/2014 - 1:19am
Dear Haskellians and CurriedOnes, Splicious is now accepting applications for alpha user trials<http://www.splicious.net/> . To learn more about splicious, apart from that it is written in a higher-kinded functional language and makes extremely cool use of delimited continuations, please check out these links. - splicious and distributed identity<https://www.youtube.com/watch?v=Tz2pmVGgrG4> - splicious, BitCoin, content creation, curation, and sharing<https://www.youtube.com/watch?v=f700b6IHZcc> - Vlad Patryshev's review of splicious<https://www.youtube.com/watch?v=nRmu9-AL2OM> - The specialK white paper<https://docs.google.com/document/d/1aM5OIJWOyW89rHdUg6d9-YVbItdtxxiosP_fXZQaRdg/edit#> - A link to our crowd funding site<http://www.rockethub.com/projects/42500-splicious> Love to all, --greg
Categories: Offsite Discussion

A Haskell Reading List

del.icio.us/haskell - Tue, 05/06/2014 - 10:03pm
Categories: Offsite Blogs

How do you find the definition a function when all you have is a huge set of input/output pairs?

Haskell on Reddit - Tue, 05/06/2014 - 8:39pm

Suppose that you were given a list of input/ouput pairs:

f 0 = 0 f 1 = 2 f 2 = 1 f 3 = -1 f 4 = 0 f 5 = 0 f 6 = -76 f 7 = -3 f 8 = 3 f 9 = -1 f 10 = -1 f 11 = -6 f 12 = -1 f 13 = -1 f 14 = 4 f 15 = -2 f 16 = -10 f 17 = 0 f 18 = 0 f 19 = -1 f 20 = 2 f 21 = 3 f 22 = 0 f 23 = 4 f 24 = 2 f 25 = -1 f 26 = 0 f 27 = 0 f 28 = -4 f 29 = -2 f 30 = -14

Now suppose you were asked to find the definition of f. How would you do it? Spoil.

submitted by SrPeixinho
[link] [18 comments]
Categories: Incoming News

happstack-lite

del.icio.us/haskell - Tue, 05/06/2014 - 7:44pm
Categories: Offsite Blogs

happstack-lite

del.icio.us/haskell - Tue, 05/06/2014 - 7:44pm
Categories: Offsite Blogs

DDC - HaskellWiki

del.icio.us/haskell - Tue, 05/06/2014 - 5:40pm
Categories: Offsite Blogs

transformers 0.4: change in accessor function exports?

libraries list - Tue, 05/06/2014 - 5:16pm
One of the changes[1] in transformers 0.4 is as follows: 0.3: newtype Identity a = Identity { runIdentity :: a } 0.4: newtype Identity a = Identity a runIdentity (Identity x) = x While this may seem benign, I've already seen three cases where this caused breakage[2][3][4]. Is there a reason for this change in 0.4? If not, I'd like to request moving back to the previous formulation to avoid unnecessary breakage. Michael [1] http://hdiff.luite.com/cgit/transformers/commit/Data/Functor/Identity.hs?id=cabf26451206cf1e223970b2df846132300c04d9&ss=1 [2] https://github.com/fpco/streaming-commons/pull/5 [3] https://github.com/ekmett/exceptions/pull/29 [4] https://github.com/ekmett/mtl/commit/d1a6253886a99215d5ff6afe3632b27e696d40b3 _______________________________________________ Libraries mailing list Libraries< at >haskell.org http://www.haskell.org/mailman/listinfo/libraries
Categories: Offsite Discussion

Writing a Game Loop in Haskell

del.icio.us/haskell - Tue, 05/06/2014 - 1:39pm
Categories: Offsite Blogs

Haskell Functors Tutorial

Haskell on Reddit - Tue, 05/06/2014 - 11:58am
Categories: Incoming News

Potential usefulness of insert/append array primitives.

Haskell on Reddit - Tue, 05/06/2014 - 9:43am

Lately I've been familiarizing myself with low-level performance hackery. I also perused the Data.HashMap sources, and in particular it started to bug me that doing snoc/append/insert on primitive arrays is not very efficient in the current state of affairs.

The core of the problem is that we can't have uninitialized arrays lying around, because the GC would try to follow the junk data, believing them to be valid pointers. So we can allocate unboxed ByteArrays uninitialized, but not boxed Arrays, and thus we have to initialize fresh arrays only to overwrite them a moment later.

I did a little benchmark on snoccing. It emulates a primitive snoc in a horribly unsafe way: it uses thawArray to copy one more element than there actually is in the source array, and then writes the new element to the back. Of course, this is a bounds error and possibly a GC mess-up, but it works at least for demonstration purposes.

Here it is. The speedup seems to be significant (1,5x - 2,5x). Primitive insertion could be similarly faster (which, unlike snoc, I couldn't test with a hack). HashMap does lots and lots of array insertions so it might benefit considerably from this.

Is this a kind of thing that would be sensible to implement? I'm posting here instead of to GHC trac because at the moment I am entirely unfamiliar with the GHC codebase or development process.

submitted by Puttamalac
[link] [14 comments]
Categories: Incoming News

A Haskell Reading List

del.icio.us/haskell - Tue, 05/06/2014 - 8:36am
Categories: Offsite Blogs

Cabal exit codes when work to be done

haskell-cafe - Tue, 05/06/2014 - 7:45am
Is there a way to run e.g. `cabal install --only-dependencies` and have it return a non-zero exit code if, for instance, there IS something to do? I tried `--dry-run` but the exit code is still 0 if something is missing. [or have it return non-zero if there isn't work to do, or...] AfC Sydney
Categories: Offsite Discussion

Simon Michael: Well-behaved Hakyll blog posts, continued

Planet Haskell - Tue, 05/06/2014 - 7:40am

More hakyll blog fixes:

Ugly things showing on planets

My posts were showing unwanted things on planet haskell - double heading, redundant date, tag links, and ugly disqus html. By comparing with Jasper Van der Jeugt’s blog, I found the problem: I was snapshotting content for the feed at the wrong time, after applying the post template:

>>= return . fmap demoteHeaders >>= loadAndApplyTemplate "templates/post.html" (postCtx tags) >>= saveSnapshot "content" >>= loadAndApplyTemplate "templates/default.html" defaultContext

Better:

>>= saveSnapshot "content" -- >>= return . fmap demoteHeaders >>= loadAndApplyTemplate "templates/post.html" (postCtx tags) >>= loadAndApplyTemplate "templates/default.html" defaultContext

Manual feed publishing

The main blog feed is now generated with a _ prefix, and I must manually rename it (with make feed) to make it live it on Planet Haskell. This will hopefully reduce snafus (and not create new ones).

./site.hs 95 - create ["blog.xml"] $ do + create ["_blog.xml"] $ do ./Makefile 14 +feed: _site/blog.xml + +_site/blog.xml: _site/_blog.xml + cp _site/_blog.xml _site/blog.xml +

Better HTML titles

Changed the “Joyful Systems” prefix to a suffix in the HTML page titles, making search results and browser tab names more useful.

Categories: Offsite Blogs

Is it an error to call hGetLine on a non-blocking Handle?

libraries list - Tue, 05/06/2014 - 6:04am
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi folks: I could really use an expert eye on this. I'm trying to get to the bottom of a very tenacious bug in the GHC Builder. The details of how this happens are documented separately for reference: https://gist.github.com/AlainODea/dc841046524cd7833da8 The Handles involved are returned by System.Process.runInteractiveProcess. They are non-blocking at the Illumos kernel level. It appears that maybeFillReadBuffer (called by hGetLine under the hood) treats EAGAIN as an error: http://hackage.haskell.org/package/base-4.7.0.0/docs/src/GHC-IO-Handle-Text.html#maybeFillReadBuffer Is it expected that runInteractiveProcess would return non-blocking Handles for stdout and stderr? Is it an error to call hGetLine on a non-blocking Handle? Thanks, Alain -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBAgAGBQJTaG1jAAoJEP0rIXJNjNSAxpwH/immeV301FEZx9o6Q0ODCuqK AUBnDHcjS9VBqhJ7XnuwkWXi83qNJhoi9P
Categories: Offsite Discussion

Philip Wadler: Reset the Net

Planet Haskell - Tue, 05/06/2014 - 5:00am
If you don't like that GCHQ and the NSA can listen in on all your network activity, here is your chance to Reset the Net.
Today, a coalition of thousands of Internet users, companies and organizations launched a campaign for a day of action to “Reset The Net” on June 5th, 2014, the anniversary of the first NSA surveillance story revealed by whistleblower Edward Snowden. Tens of thousands of internet activists, companies and organizations committed to preserving free speech and basic rights on the Internet by taking steps to shutting off the government’s mass surveillance capabilities.
Watch the campaign video and see a full list of participants here: http://ResetTheNet.org More than 20 organizations and companies support the launch of the campaign including Fight For The Future (who initiated the campaign) along with reddit, CREDO Mobile, Imgur, Greenpeace, Libertarian Party, FireDogLake, Thunderclap, DuckDuckGo, Disconnect.Me, Demand Progress,  Access, Free Press, Restore the Fourth, AIDS Policy Project, PolitiHacks, OpenMedia, Free Software Foundation, Bill of Rights Defense Committee, Code Pink, Popular Resistance, Participatory Politics Foundation, BoingBoing, Public Knowledge, Amicus, New America Foundation’s Open Technology Institute, Progressive Change Campaign Committee, Student Net Alliance, and the Center for Democracy and Technology. ...  Internet users are invited to join in on the day of Reset The Net to install privacy and encryption tools and secure their personal digital footprint against intrusive surveillance.Technical information here and press release here.
Categories: Offsite Blogs