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Speed up ghc -O2

haskell-cafe - 0 sec ago
My program reads a xls file and creates a haskell program that does exactly the same as what the xls does. Every cell in the xls is a function and contains 2 lines: the type declaration and 1 line the implementation. The type of a cell is XlsCell. data XlsCell = Reader ExternalCells XlsCellRes data XlsCellRes = XlsCellString String | XlsCellBool Bool | ..... type ExternalCells = Map String XlsCellRes -- search (or set) a value of a cell by its name. The externalCells are for the cells you can change at runtime. The generated program was first 30000 lines. When I compiled it with ghc 7.8.3. -O0 the program worked, but was terribly slow. With -O2 I got: out of memory. With a few trics the generated code is now split up in 2 files 5000 and 10000 lines. I've upgraded to ghc 7.8.4. If I do ghc -O2 the program takes more then 4 hours to compile. The -O2 compilation is essential. The resulting program is much (more then 10x) faster then without -O2. What can I do (changes in the generated code, changes
Categories: Offsite Discussion

Increased memory usage with GHC 7.10.1

glasgow-user - 0 sec ago
Forall hi, I just uprgaded both of my machines to use GHC 7.10.1. I keep sandboxed installations of GHC and this means I had to rebuild Agda and Idris because the binaries built with GHC 7.8.4 were stored inside deactivated 7.8.4 sandbox. Sadly, I had problems building both Agda and Idris due to GHC taking up all of available memory. With Idris the problematic module was Idris.ElabTerm (~2900LOC). The interesting part of the story is that when I do a clean build of Idris GHC consumes all of memory when compiling that module and I have to kill the build. But when I restart the build after killing GHC the module is compiled using a reasonable amount of memory and within reasonable time. With Agda the problematic module is Agda.TypeChecking.Serialise (~2000LOC). The trick with killing the build and restarting it didn't work in this case. I had to compile Agda with GHC 7.8.4 (which works without problems though the mentioned module still requires a lot of memory) and alter my setup so that Agda binar
Categories: Offsite Discussion

Stable location for monomorphic foldr?

libraries list - 0 sec ago
Hi, I just stumbled over a FTP breakage: A RULES with "foldr" on the left hand side would no longer fire, because it would refer to Foldable.foldr, and not the monomorphic foldr. Adding #if MIN_VERSION_base(4,8,0) import Prelude hiding (foldr) import GHC.OldList (foldr) #endif to the file solved the problem for now, but GHC.OldList is supposed to go away eventually, so I believe we need a permanent location for the monomorphic foldr. Or will we simply not get rid of GHC.OldList at all? (One could argue that "foldr" on the left-hand-side of a RULE should work and that this is a GHC bug, though.) Greetings, Joachim
Categories: Offsite Discussion

Specify OS version

haskell-cafe - 0 sec ago
Hi Cafe! I have program written in Haskell and Swift that runs on Mac. This program uses some features that was introduced in last version of OS X “Yosemite” 10.10, but some of my users use previous version "Maverics " 10.9. Is there some technique that allows me to extend my cabal file and specify which *version* of os is currently in use and don't load some of modules? AFAIK, Cabal's `conditional` doesn't provide such mechanism, but something like ``` if os(osx) && ver(=10.10) if os(osx) && ver(<=10.9) ``` will be nice. Maybe there is other approach to this problem?I don't want to use `CPP` extension to handle this within code. Thanks -- Best regards, Sergey Bushnyak _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe< at >haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
Categories: Offsite Discussion

DSLDI: 3rd Workshop on Domain-Specific Language Designand Implementation (EXTENDED DEADLINE)

********************************************************************* SECOND CALL FOR TALK PROPOSALS DSLDI 2015 Third Workshop on Domain-Specific Language Design and Implementation July 7, 2015 Prague, Czech Republic Co-located with ECOOP http://2015.ecoop.org/track/dsldi-2015-papers ********************************************************************* EXTENDED Deadline for talk proposals: 9th of April, 2015 If designed and implemented well, domain-specific languages (DSLs) combine the best features of general-purpose programming languages (e.g., performance) with high productivity (e.g., ease of programming). *** Workshop Goal *** The goal of the DSLDI workshop is to bring together researchers and practitioners interested in sharing ideas on how DSLs should be designed, implemented, supported by tools, and applied in realistic application contexts. We are both interested in discovering how already known domains such as graph processing or machine learning can be best supported by DSLs, but also in e
Categories: Incoming News

Binary bloat in 7.10

glasgow-user - 3 min 57 sec ago
Why do the 7.10 libraries take up so much more space than 7.8? For example, using the same build options and strip --strip-unneeded, 7.8 leaves me with 15M libHSCabal-1.18.1.5.a 17M HSCabal-1.18.1.5.o whereas 7.10 balloons to 23M HSCabal-1.22.2.0-HWT8QvVfJLn2ubvobpycJY.o 53M libHSCabal-1.22.2.0-HWT8QvVfJLn2ubvobpycJY.a -- View this message in context: http://haskell.1045720.n5.nabble.com/Binary-bloat-in-7-10-tp5768067.html Sent from the Haskell - Glasgow-haskell-users mailing list archive at Nabble.com.
Categories: Offsite Discussion

Journal of Functional Programming - Call for PhDAbstracts

haskell-cafe - 1 hour 11 min ago
============================================================ CALL FOR PHD ABSTRACTS Journal of Functional Programming Deadline: 30th April 2015 http://tinyurl.com/jfp-phd-abstracts ============================================================ PREAMBLE: Many students complete PhDs in functional programming each year, but there is currently no common location in which to promote and advertise the resulting work. The Journal of Functional Programming would like to change that! As a service to the community, JFP recently launched a new feature, in the form of a regular publication of abstracts from PhD dissertations that were completed during the previous year. The abstracts are made freely available on the JFP website, i.e. not behind any paywall, and do not require any transfer for copyright, merely a license from the author. Please submit dissertation abstracts according to the instructions below. A dissertation is eligible if parts of it have or could have appeared in JFP, that is, if it is in the
Categories: Offsite Discussion

Journal of Functional Programming - Call for PhD Abstracts

General haskell list - 1 hour 11 min ago
============================================================ CALL FOR PHD ABSTRACTS Journal of Functional Programming Deadline: 30th April 2015 http://tinyurl.com/jfp-phd-abstracts ============================================================ PREAMBLE: Many students complete PhDs in functional programming each year, but there is currently no common location in which to promote and advertise the resulting work. The Journal of Functional Programming would like to change that! As a service to the community, JFP recently launched a new feature, in the form of a regular publication of abstracts from PhD dissertations that were completed during the previous year. The abstracts are made freely available on the JFP website, i.e. not behind any paywall, and do not require any transfer for copyright, merely a license from the author. Please submit dissertation abstracts according to the instructions below. A dissertation is eligible if parts of it have or could have appeared in JFP, that is, if it is in the
Categories: Incoming News

ANNOUNCE: Parsed 0.0.1

haskell-cafe - 1 hour 44 min ago
I'm pleased to announce the first release of the Parsed library (pronounced par-séd). Parsed is a reimplementation of Haskell's excellent Parsec library in the Unix shell. In particular, the Unix pipe operator | corresponds exactly to Haskell's Applicative bind *>. Here's a quick example to get a feel for the syntax. The following bash one liner creates a parser for matching balanced parenthesis: ``` parens() { choice "$1" "match '(' | parens \"$1\" | match ')'"; } ``` For more detailed examples and implementation notes, please see the Parsed paper accepted at SIGBOVIK2015: https://github.com/mikeizbicki/parsed/raw/master/sigbovik2015/paper.pdf You can download Parsed from its github page at: https://github.com/mikeizbicki/parsed
Categories: Offsite Discussion

Functor is now a superclass of Monad in GHC HEAD

Haskell on Reddit - 2 hours 39 min ago

Happy April, everyone

submitted by tel
[link] [8 comments]
Categories: Incoming News

ANNOUNCE: Arion

General haskell list - 3 hours 27 min ago
Three of us have been working on Arion for a week or two now. It's a watcher and runner for Hspec tests. It associates source files with test files, watches the file system, and when a file changes it runs the corresponding test files instead of running all the test files, making the process of red-green-refactor faster. We are happy to announce that we have a nice and stable version (0.1.0.8). Thanks to the folks at hspec.github.io for listing our project on their website. To know more, please visit - https://github.com/karun012/arion Feedback/Feature Requests/Everything else welcome. _______________________________________________ Haskell mailing list Haskell< at >haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell
Categories: Incoming News

An Easy Solution to PVP Bounds and Cabal Hell

haskell-cafe - 5 hours 12 min ago
Recently there has been some discussion about how we can fix the problem of “Cabal Hell”. Some people advocate restrictive upper bounds, to prevent packages from being broken by new updates. Some other people point out that too-restrictive bounds can lead to bad install plans, since some packages might want newer versions of some dependencies, and others older versions. Still other people say that we can _retroactively_ fix upper bounds (in either direction) by modifying cabal files using the new features in Hackage. Some people think this is a terrible idea because it looks like we are mutating things, and this confuses hashes. In turn, these people support either nix or a nix-like approach by which packages have hashes that encompass the full versions of all their transitive dependencies. With that in hand, we can cache builds and mix-and-match to build the precise environment we want for each package while reducing redundant computation. However, the cache of all the various binary combinations may st
Categories: Offsite Discussion

Philip Wadler: Pension cuts - respond to USS

Planet Haskell - 6 hours 6 min ago

The UCU has lain down its placards and ended the strike to avoid cuts to pensions. Our one remaining hope is for members to make their outrage known in the USS consultation exercise, which ends 22 May 2015. I hope everyone with a USS pension will respond. Suggested responses from UCU Left and UCU are linked; please comment below, especially to list other suggested responses.

Universities UK argue that the reductions are necessary to avoid a deficit, but their claim has been widely criticised. A group of prominent statisticians point out Universities UK inflated the deficit by assuming a buoyant economy when predicting future salaries but assuming a recession when predicting investment returns.

In 2011, Universities UK imposed vastly reduced pensions on new hires. Old hires who pay into the pension fund for forty years receive a pension of one-half their final salary; new hires who do the same receive a pension of one-half their average salary. Basing pensions on average rather than final salary may be sensible, but to do so with no little or no adjustment in multiplier suggests employers used this as an excuse to slip in a large cut; new hires receive about 2/3 the benefits received by old hires. All staff also suffered other cuts to pensions: additional caps and less good adjustment for inflation. At the time, it was predicted that within a few years old hires would be moved to the inferior scheme for new hires, and that is what has now come to pass.

Like many in USS, employees and employers alike, I am concerned that the changes will make UK academia a less attractive option for potential scholars.



Categories: Offsite Blogs

Douglas M. Auclair (geophf): March 2015 1HaskellADay Problems and Solutions

Planet Haskell - 7 hours 42 min ago

March 2015
  • March 31st, 2015: Today's #haskell exercise has us looking for a really big pandigital prime http://lpaste.net/6128183741660528640 ... like: REALLY big. Maybe.
  • March 30th, 2015: A little math-problem to ease us into the week, suggested by @jamestanton http://lpaste.net/845208190432837632 3 consecutive integers that are co-composed
  • March 27th, 2015: Today's #haskell problem is unification of multiple free variables http://lpaste.net/370356889654919168 We find this to be 'CoSimple.' 34 lines (and a new n-to-1 data mapping-type) defining not a 'CoSimple' unifier but now an 'UnSimple' one. http://lpaste.net/8114086012700852224 Ugh!
  • March 26th, 2015: Unification is interesting! http://www.cs.uu.nl/research/techreps/repo/CS-2008/2008-027.pdf (Functional Unification paper) Let's look at the unification-problem for today's #haskell problem http://lpaste.net/1572781401336446976 We define simple unification (of up to one free logic variable) in a module called unification.simple, oddly enough. http://lpaste.net/5064654031335456768
  • March 25th, 2015: In Old Norse, words end with 'R' (not all). For today's #Haskell problem, relations end with 'R' http://lpaste.net/8067966125595426816
  • March 24th, 2015: For today's #haskell problem we learn that 'kayso' is a word, and we edge a bit more toward pure relational calculushttp://lpaste.net/5312260085655797760 A solution to this relational-calculus problem that is defined over Data/Control logic modules: http://lpaste.net/5718036917765799936
  • March 23rd, 2015: WHO KNEW a chance meeting with @webyrd at the POPL06 would lead to today's #haskell problem? http://lpaste.net/7445712320312901632 μBikini I mean: μKanren And the solution implies that monadic-list states are logic programming? http://lpaste.net/8325001449901654016 Perhaps.
  • March 19th, 2015: We now learn signal spreads ... like ... margarine! for today's #haskell problem http://lpaste.net/4389894538622140416
  • March 18th, 2015: For today's #haskell problem we learn that Jupiter's moon Europa is made from Froyo, and custard! Mmmm! http://lpaste.net/127272
  • March 17th, 2015: No quaternions were harmed in today's #haskell π-problem IN SPACE! http://lpaste.net/7134990338598371328
  • March 16th, 2105: In space, no one can here you scream "@NASA" (nor anything else for that matter. Today's #haskell problem http://lpaste.net/7238728062383161344
  • March 14th, 2015: Happy π day! A plain-text version of these NASA π-in-space puzzles are available at http://lpaste.net/7533371868384854016
  • March 13th, 2015: Okay, ladies and gentlemen, today, in honor of tomorrow being π day, let's take a #coercive #logic break and π it up! http://lpaste.net/7075392225642807296
  • March 12th, 2015: I wonder if the suitor's surname is Quinehttp://lpaste.net/5006337360527360000 for today's #haskell problem #coercive #logic
  • March 10th, 2015: For today's #haskell problem, we wonder if Balikaya is Aharmanite or Mazdaysian http://lpaste.net/6972955679380209664 #scheherazade #coercive #logic
  • March 9th, 2015: In which Iskandar is asked Kamar's Children's ages in Scheherazade's #haskell metapuzzle http://lpaste.net/8990755663210610688 #coercive #logic 
  • March 6th, 2015: Champernowne's constant for today's #haskell problem http://lpaste.net/6911025218794291200 Please let me know if you can NOT access this problem: I've marked it private as previous ones are being modified in place. DON'T DO THAT!  In which we show @geophf triumphs with brütish-forcisms for today's #haskell solution http://lpaste.net/2944338052937416704
  • March 5th, 2015: For today's #haskell problem, we ponder why they aren't calledLEFT-triangles. Is it a plot? http://lpaste.net/121797 Leftist triangles are subject to the (IO) State (monad) ... geddit? #sigh never mind anyway, solution: http://lpaste.net/122143 Or, put another way: in which we see @geophf can not have a function type that includes -> Int -> ... AND, we really need MapReduce here!
  • March 4th, 2015: Truncatable primes (11 in all) are asking to be solved in today's projecteuler.com #haskell problem http://lpaste.net/121528 This @1HaskellADay problem turned into a _TWO_day solution! Worth it? Why, yes, after redesigning _TWO_ libraries! http://lpaste.net/122503
  • March 3rd, 2015: There's more than a 1-in-a-million chance there are 'sum' double palindromic numbers in today's #haskell problem http://lpaste.net/121470 The solution was not too hard, M. Euler! http://lpaste.net/121471
  • March 2nd, 2015: What-what! abcde * fghij is equal to ... well, something, it appears. http://lpaste.net/121421 and the prob1, prob2 winners are ...http://lpaste.net/121466 A solution to today's #haskell problem.
Categories: Offsite Blogs

Journal of Functional Programming - Call for PhD Abstracts

Haskell on Reddit - 8 hours 13 min ago

CALL FOR PHD ABSTRACTS

Journal of Functional Programming

Deadline: 30th April 2015

http://tinyurl.com/jfp-phd-abstracts

PREAMBLE:

Many students complete PhDs in functional programming each year, but there is currently no common location in which to promote and advertise the resulting work. The Journal of Functional Programming would like to change that!

As a service to the community, JFP recently launched a new feature, in the form of a regular publication of abstracts from PhD dissertations that were completed during the previous year. The abstracts are made freely available on the JFP website, i.e. not behind any paywall, and do not require any transfer for copyright, merely a license from the author.

Please submit dissertation abstracts according to the instructions below. A dissertation is eligible if parts of it have or could have appeared in JFP, that is, if it is in the general area of functional programming. JFP will not have these abstracts reviewed. We welcome submissions from both the PhD student and PhD advisor/ supervisor although we encourage them to coordinate.

SUBMISSION:

Please submit the following information to Graham Hutton graham.hutton@nottingham.ac.uk by 30th April 2015.

o Dissertation title: (including any subtitle)

o Student: (full name)

o Awarding institution: (full name and country)

o Date of PhD award: (month and year; depending on the institution, this may be the date of the viva, corrections being approved, graduation ceremony, or otherwise)

o Advisor/supervisor: (full names)

o Dissertation URL: (please provide a permanently accessible link to the dissertation if you have one, such as to an institutional repository or other public archive; links to personal web pages should be considered a last resort)

o Dissertation abstract: (plain text, maximum 1000 words; you may use \emph{...} for emphasis, but we prefer no other markup or formatting in the abstract, but do get in touch if this causes significant problems)

Please do not submit a copy of the dissertation itself, as this is not required. JFP reserves the right to decline to publish abstracts that are not deemed appropriate.

PHD ABSTRACT EDITOR:

Graham Hutton School of Computer Science University of Nottingham Nottingham NG8 1BB United Kingdom

submitted by grahamhutton
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Categories: Incoming News

Bird's Functional Pearls in OCaml

Haskell on Reddit - 8 hours 23 min ago

If anyone is interested in Richard Bird's Pearls of Functional Algorithm Design, there's an interesting site that's implementing the pearls in OCaml instead of Haskell.

TypeOCaml

Lots of explanations of the algorithms with diagrams.

submitted by derek-mcloughlin
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Categories: Incoming News