Hector Guilarte | 1 Mar 2010 01:21
Picon
Gravatar

Re: ANN: Try Haskell! An interactive tutorial in your browser

Nice!


I tried it and it worked perfectly, however I tried it again 45 minutes later (about 15 minutes ago) and when I pressed Enter nothing happened. I couldn't enter any expressions. The only expression I could enter was help

Hector

On Sun, Feb 28, 2010 at 6:18 PM, Benjamin L. Russell <DekuDekuplex <at> yahoo.com> wrote:
According to the top page of HaskellWiki (see http://www.haskell.org/)
(under "February 2010" under "1 Headlines"), there is an alpha version
of a new interactive, online Haskell interpreter entitled "Try Haskell!"
at http://tryhaskell.org/.

The top panel of the page features an interactive interpreter, while the
bottom panel features a text tutorial.  The user types in commands
in the top panel according to the text tutorial, and the interpreter
responds with output.  There is also a "Reset" button in the upper right
corner of the tool which resets the state of both panels to the default
state.

I just tried it out, and it appears to have been completed up to Lesson
3.  So far, it apparently teaches up to lists.  It was fun to try out.

This tutorial somehow reminded me of an interactive Scheme tutorial,
"Lists And Lists," copyrighted in 1996 by Andrew Plotkin, at
http://parchment.googlecode.com/svn/trunk/parchment.html?story=http://parchment.toolness.com/if-archive/games/zcode/lists.z5.js.
That tutorial was arranged in the style of an adventure game, while this
tutorial is more similar to a very similar Ruby tutorial, "try ruby! (in
your browser)" at http://TryRuby.org/.

It could be fun if somebody could come up with a Haskell version of
the above-mentioned"Lists And Lists," which also includes a text-based
Scheme reference on the virtual computer within the adventure game.

-- Benjamin L. Russell
--
Benjamin L. Russell  /   DekuDekuplex at Yahoo dot com
http://dekudekuplex.wordpress.com/
Translator/Interpreter
/ Mobile:  +011 81 80-3603-6725
"Furuike ya, kawazu tobikomu mizu no oto." -- Matsuo Basho^

_______________________________________________
Haskell mailing list
Haskell <at> haskell.org
http://www.haskell.org/mailman/listinfo/haskell

_______________________________________________
Haskell mailing list
Haskell <at> haskell.org
http://www.haskell.org/mailman/listinfo/haskell
Ivan Miljenovic | 1 Mar 2010 01:29
Picon
Gravatar

Re: ANN: Try Haskell! An interactive tutorial in your browser

On 1 March 2010 11:21, Hector Guilarte <hectorg87 <at> gmail.com> wrote:
> I tried it and it worked perfectly, however I tried it again 45 minutes
> later (about 15 minutes ago) and when I pressed Enter nothing happened. I
> couldn't enter any expressions. The only expression I could enter was help
> Hector

"stepN" works for me as well (with N \in Z^+).

--

-- 
Ivan Lazar Miljenovic
Ivan.Miljenovic <at> gmail.com
IvanMiljenovic.wordpress.com
Temur Kutsia | 1 Mar 2010 09:46
Picon

2nd CfP: PPDP'10


======================================================================
                          Call for Papers
                             PPDP 2010
                12th International ACM SIGPLAN Symposium on
          Principles and Practice of Declarative Programming
                  Hagenberg, Austria, 26-28 July 2010
                     (co-located with LOPSTR 2010)
          http://www.risc.uni-linz.ac.at/conferences/ppdp2010/
======================================================================

PPDP 2010 aims to bring together researchers from the declarative
programming communities, including those working in the logic,
constraint and functional programming paradigms, but also embracing a
variety of other paradigms such as visual programming, executable
specification languages, database languages, AI languages and
knowledge representation languages used, for example, in the semantic
web. The goal is to stimulate research in the use of logical
formalisms and methods for specifying, performing, and analysing
computations, including mechanisms for mobility, modularity,
concurrency, object-orientation, security, and static analysis. Papers
related to the use of declarative paradigms and tools in industry and
education are especially solicited.

The conference will take place in July 2010 in the Castle of
Hagenberg, Austria, colocated with the 20th International Symposium on
Logic-Based Program Synthesis and Transformation (LOPSTR 2010),
organised by the Research Institute for Symbolic Computation (RISC) of
the Johannes Kepler University Linz.

Topics:
     * Logic, Constraint, and Functional Programming
     * Database, AI and Knowledge Representation Languages
     * Visual Programming
     * Executable Specification Languages
     * Applications of Declarative Programming
     * Methodologies: Program Design and Development
     * Declarative Aspects of Object-Oriented Programming
     * Concurrent Extensions to Declarative Languages
     * Declarative Mobile Computing
     * Integration of Paradigms
     * Proof Theoretic and Semantic Foundations
     * Type and Module Systems
     * Program Analysis and Verification
     * Program Transformation
     * Abstract Machines and Compilation
     * Programming Environments
The list above is not exhaustive - submissions describing  new and
interesting ideas relating broadly to declarative programming are
encouraged.

Submission guidelines:
Papers should be submitted via the Easychair submission website
for PPDP 2010:
http://www.easychair.org/conferences/?conf=ppdp2010
Papers should consist of the equivalent of 12 pages under the
ACM formatting guidelines. These guidelines are available online,
along with formatting templates or style files.
Submitted papers will be judged on the basis of significance,
relevance, correctness, originality, and clarity. They should include
a clear identification of what has been accomplished and why it is
significant. They must describe original, previously unpublished work
that has not been simultaneously submitted for publication
elsewhere. Authors who wish to provide additional material to the
reviewers beyond the 12-page limit can do so in clearly marked
appendices: reviewers are not required to read such appendices.
No simultaneous submission to other publication outlets (either a
conference or a journal) is allowed.

Proceedings:
The proceedings will be published by ACM Press. Authors of accepted
papers will be required to sign a copyright form.  Camera ready papers
for accepted papers should be prepared and submitted according to the
final instructions that will be sent by the publisher after
notification of acceptance.

Invited Speakers:
Maria Paola Bonacina (Università degli Studi di Verona, Italy)
Sumit Gulwani (Microsoft Research)

Important Dates:
# Submission: title and abstract: 15 March 2010
               full paper: 21 March 2010
# Notification:  23 April 2010
# Final version: 12 May 2010
# Symposium: 26-28 July 2010

Programme Committee:
Elvira Albert (Spain)
Sergio Antoy (US)
Frederic Blanqui (China)
Michele Bugliesi (Italy)
Giuseppe Castagna (France)
Mariangiola Dezani (Italy)
Francois Fages (France)
Maribel Fernandez (UK), chair
Joxan Jaffar (Singapore)
Andy King (UK)
Temur Kutsia (Austria)
Francisco Lopez Fraguas (Spain)
Ian Mackie (France)
Henrik Nilsson (UK)
Albert Rubio (Spain)
Kazunori Ueda (Japan)
Philip Wadler (UK)

Symposium Chairs:
Temur Kutsia and Wolfgang Schreiner (Austria)

For more information, please contact the chairs:
Maribel Fernandez
King's College London, UK
Email: Maribel.Fernandez <at> kcl.ac.uk

Temur Kutsia and Wolfgang Schreiner
Research Institute for Symbolic Computation
Johannes Kepler University Linz
Email: kutsia <at> risc.uni-linz.ac.at
Jon Sneyers | 1 Mar 2010 17:40
Picon

Call for Participation: CHR Summer School


- Call for Participation -

First International Summer School on CHR:
Programming and Reasoning with Rules and Constraints

August 30 - September 3 2010
Leuven, Belgium

Website:   http://www.cs.kuleuven.be/~dtai/CHR/summerschool

****************************************************************************
* EARLY REGISTRATION DISCOUNT: When registering (including payment) before *
*               March 31, the registration fee will be reduced by 20 euro! *
*                                                                          *
* Additional early registration incentive:                                 *
* The first 7 registrants get a FREE copy of the book                      *
*     "Constraint Handling Rules - Current Research Topics"                *
****************************************************************************

The aim of the summer school is to familiarize the participants with
state-of-the-art high-level declarative programming with rules and
constraints as well as providing insights into the analysis of programs
based on these concepts. The courses cover a wide range from theory to
practice.

The summer school will be based on the advanced high-level rule-based
formalism and programming language Constraint Handling Rules (CHR)
http://constraint-handling-rules.org/

Intended Audience:

The summer school provides courses at various levels. It is open to anyone 
interested. It aims at Phd. students, but also post-docs, interested 
researchers and master students as well as interested parties from 
industry. Besides a working knowledge of English, there are no 
prerequisites. A basic knowledge of logic and Prolog that is usually 
covered in undergraduate classes could be helpful.

Lectures and Courses:

The programming language CHR will be introduced by several lecturers on the 
first day of the summer school.

- Slim Abdennadher, GUC, Egypt
         Analysis of CHR Solvers
- Henning Christiansen, U. Roskilde, Denmark
         Abduction and language processing with CHR
- Thom Fruehwirth, University Ulm, Germany
         CHR - a common platform for rule-based approaches
- Jon Sneyers, K.U.Leuven, Belgium
         Computability and Complexity of CHR
- Peter Van Weert, K.U.Leuven, Belgium
         Implementation of CHR Systems

A final evaluation for each course is possible through a final exam or 
project as determined by the instructor. The daily schedule admits 
laboratory, recitation or working group activities to be organized in 
addition to lectures.

Registration:

The registration fee for the School is 300 euro and includes teaching 
material with book, as well as accomodation and coffee breaks. Meals are 
not included. Attendance is limited to 20 students and will be allocated 
on a first-come- first-served basis. Without accommodation the 
registration fee is reduced to 200 euro.

Location:

Leuven is a lively student town in Belgium with a very high density of 
pubs offering hundreds of types of local beers.

Organization:

Thom Fruehwirth, University of Ulm, Germany
Jon Sneyers, K.U. Leuven, Belgium
Peter Van Weert, K.U. Leuven, Belgium

Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm
German Vidal | 1 Mar 2010 20:44
Picon

CFP CICLOPS-WLPE 2010 at FLoC (Edinburgh, 15 July)

*******************************************************************
                            Call For Papers

                           CICLOPS-WLPE 2010

                           Joint Workshop on
     Implementation of Constraint Logic Programming Systems
                                 and
         Logic-based Methods in Programming Environments

                         Edinburgh, Scotland, U.K.
                            July 15, 2010
               http://users.dsic.upv.es/~ciclops-wlpe10/

                        Satellite event of the
  26th International Conference on Logic Programming (ICLP 2010)
               http://www.floc-conference.org/ICLP-home.html

*******************************************************************

Important Dates:

Paper Submission:          March 31, 2010
Notification of Authors:   April 29, 2010
Camera-ready:              May 17, 2010 (tentative)
Workshop:                  July 15, 2010

Invited talks:

Programming with Boolean Satisfaction
Michael Codish, Ben-Gurion University of the Negev (Israel)

Solving Constraint Satisfaction Problems by a SAT Solver
Naoyuki Tamura, Kobe University (Japan)

Workshop description

CICLOPS is a series of colloquia on the implementation of constraint
logic programming. Logic and Constraint programming is an important
declarative programming paradigm. The features offered by this
paradigm such as rule-basedness, pattern matching, automated
backtracking, recursion, tabling, and constraint solving have been
proved convenient for many programming tasks. Recent improvements in
implementation technologies combined with advances in hardware and
systems software have made logic and constraint programming a viable
choice for many real-world problems.

CICLOPS'10 continues a tradition of successful workshops on
Implementations of Logic Programming Systems, previously held with in
Budapest (1993) and Ithaca (1994), the Compulog Net workshops on
Parallelism and Implementation Technologies held in Madrid (1993 and
1994), Utrecht (1995) and Bonn (1996), the Workshop on Parallelism and
Implementation Technology for (Constraint) Logic Programming Languages
held in Port Jefferson (1997), Manchester (1998), Las Cruces (1999),
and London (2000), and more recently the Colloquium on Implementation
of Constraint and LOgic Programming Systems in Paphos (Cyprus, 2001),
Copenhagen (2002), Mumbai (2003), Saint Malo (France, 2004), Sitges
(Spain, 2005), Seattle (U.S.A., 2006), Porto (Portugal, 2007), Udine
(Italy, 2008), and Pasadena (U.S.A, 2009).

WLPE is a series of workshops on practical logic-based software
development methods and tools. Software plays a crucial role in modern
society. While software keeps on growing in size and complexity, it is
more than ever required to be delivered on time, free of error and
meeting the most stringent efficiency requirements. Thus more demands
are placed on the software developer, and consequently, the need for
methods and tools that support the programmer in every aspect of the
software development process is widely recognized. Logic plays a
fundamental role in analysis, verification and optimization in all
programming languages, not only in those based directly on logic. The
use of logic-based techniques in software development is a very active
area in computing; emerging programming paradigms and growing
complexity of the properties to be verified pose new challenges for
the community, while emerging reasoning techniques can be exploited.

WLPE'10 continues the series of successful international workshops on
logic programming environments held in Ohio, USA (1989), Eilat, Israel
(1990), Paris, France (1991), Washington D.C., USA (1992), Vancouver,
Canada (1993), Santa Margherita Ligure, Italy (1994), Portland, USA
(1995), Leuven, Belgium (1997), Las Cruces, USA (1999), Paphos, Cyprus
(2001), Copenhagen, Denmark (2002), Mumbai, India (2003), Saint Malo,
France (2004), Sitges (Barcelona), Spain (2005), Seattle, USA (2006),
Porto, Portugal (2007) and Udine, Italy (2008). More information about
the series of WLPE workshops can be found at
http://www.cs.usask.ca/projects/envlop/WLPE/

CICLOPS-WLPE 2010 aims at bringing together, in an informal setting,
people involved in research in the design and implementation of logic
and constraint programming languages and systems and on logic-based
methods and tools which support program development and analysis. In
addition to papers describing more conceptual and theoretical work,
papers describing the implementation of, and experience with, such
tools will be welcome.

Topics:

    * Abstract machines and compilation techniques
    * Compile-time analysis and its application to code generation
    * Memory management, indexing, and garbage collection issues
    * Profiling tools and performance evaluation
    * Implementation of concurrent, parallel, and distributed systems
    * Extensions such as tabling, constraints, probabilistic  
reasoning, and learning
    * New features such as ASP and coinduction
    * Object-oriented and module systems
    * Integration with other systems such as CP, SAT, LP/MLP, and  
Database systems
    * Experiences from using systems in real-life applications
    * Static and dynamic analysis
    * Debugging and testing
    * Program verification and validation,
    * Code generation from specifications,
    * Termination analysis,
    * Constraints
    * Rewriting
    * Profiling and performance analysis,
    * Type and mode analysis,
    * Module systems,
    * Optimization tools,
    * Program understanding,
    * Refactoring
    * Logical meta-languages

Authors who are interested in taking part in the workshop, but are
unsure if their work falls within its scope, are invited to contact
the organizers and will be given suitable advice.

Submission details:

All papers must be written in English, in Springer LNCS format
(http://www.springeronline.com/lncs/), and not exceed 15
pages. Submissions must be made through the easychair system available
at

http://www.easychair.org/conferences/?conf=ciclopswlpe2010

All accepted papers will be included in the workshop proceedings to be
published as a technical report and distributed at the workshop, as
well as electronically at the Computing Research Repository (CoRR).

Program Committee:

Rafael Caballero, Complutense University Madrid, Spain
Vitor Santos Costa, Universidade do Porto, Portugal
Martin Gebser, University of Potsdam, Germany
Samir Genaim, Complutense University of Madrid, Spain
Yoshitaka Kameya, Tokyo Institute of Technology, Japan
Andy King, University of Kent, UK
Huiqing Li, University of Kent, U.K.
Lunjin Lu, Oakland University, MI, USA
Paulo Moura, Universidade da Beira Interior, Portugal
Ulrich Neumerkel, Technische Universität Wien, Austria
Enrico Pontelli, New Mexico State University, USA
Joachim Schimpf, Monash University, Australia
Peter Schneider-Kamp, University of Southern Denmark, Denmark
Wim Vanhoof, University of Namur, Belgium
German Vidal, Technical University of Valencia
Neng-Fa Zhou, The City University of New York, NY, USA

Workshop organizers:

German Vidal
DSIC, Universidad Politecnica de Valencia
Camino de Vera S/N, 46022 Valencia, Spain
http://www.dsic.upv.es/~gvidal/

Neng-Fa Zhou
Department of Computer and Information Science, Brooklyn College
The City University of New York
2900 Bedford Avenue, Brooklyn, NY 11210-2889
http://www.sci.brooklyn.cuny.edu/~zhou/
Maciej Piechotka | 4 Mar 2010 14:20
Picon

ANN: iteratee-parsec 0.0.2

Iteratee-parsec is a library which allows to have a parsec (3) parser in
IterateeG monad.

It contains 2 implementations:
- John Lato's on public domain. It is based on monoid and design with
short parsers in mind.
- Mine on MIT. It is based on single-linked mutable list. It seems to be
significantly faster for larger parsers - at least in some cases - but
it requires a monad with references (such as for example IO or ST).

Version 0.0.2 does not differ much from 0.0.1 except that it is
up-to-date with parsec 3.1.0 (version 0.0.1 is not).

Regards
_______________________________________________
Haskell mailing list
Haskell <at> haskell.org
http://www.haskell.org/mailman/listinfo/haskell
Sebastian Fischer | 7 Mar 2010 18:10
Picon
Gravatar

ANNOUNCE: barchart-0.1.1

barchart is a command-line program with associated Haskell library for  
generating bar charts, for example, from CSV files. It has special  
support for creating charts from data generated by the Haskell  
benchmarking tools criterion and progression.

Instead of drawing bars of different benchmarks next to each other  
like progression does, barchart draws one bar for each benchmarked  
implementation where the benchmarks are represented as blocks of the  
same bar. As a consequence, one can recognise on first sight, which  
implementation is the fastest _in total_ because the hight of each bar  
is the sum of run times of all benchmarks for an implementation.  
Another difference to progression is that barchart is (only) a post  
processor and you usually do not import barchart modules into your  
Haskell code.

Please refer to the project website for more information:

     http://sebfisch.github.com/haskell-barchart/

I would not have written this program without the Diagrams library by  
Brent Yorgey and the CmdArgs package by Neil Mitchell. Thank you for  
your excellent libraries!

I hope barchart is useful for some of you!

Sebastian

--

-- 
Underestimating the novelty of the future is a time-honored tradition.
(D.G.)
Eric Y. Kow | 7 Mar 2010 21:43
Favicon
Gravatar

Re: ANNOUNCE: barchart-0.1.1

On Sun, Mar 07, 2010 at 18:10:31 +0100, Sebastian Fischer wrote:
> barchart is a command-line program with associated Haskell library
> for generating bar charts, for example, from CSV files. It has
> special support for creating charts from data generated by the
> Haskell benchmarking tools criterion and progression.

Sounds like this could be really useful for darcs-benchmark!

Meanwhile, I just thought I should point out a potentially complementary
library called 'tabular'.  Tabular lets you generate tables in various
formats from a single representation.  So you could spit out CSV values
for barchart on the one hand and LaTeX on the other hand and somehow
stitch the two into a nice little PDF.

  http://hackage.haskell.org/package/tabular

Right now, the formats it knows about are an ASCII art format, HTML, CSV
and LaTeX.  For darcs-benchmark, we use a custom ReStructredText
renderer.  Maybe in the future, a Pandoc renderer would be useful.

Now row/column spans, yet, unfortunately :-(

--

-- 
Eric Kow <http://www.nltg.brighton.ac.uk/home/Eric.Kow>
PGP Key ID: 08AC04F9
_______________________________________________
Haskell mailing list
Haskell <at> haskell.org
http://www.haskell.org/mailman/listinfo/haskell
Edgar Z. Alvarenga | 7 Mar 2010 21:49

Recursive definition of fibonacci with Data.Vector

Hello,

why I can't define a recursive vector using Data.Vector, like in
the example:

import qualified Data.Vector as V

let fib = 0 `V.cons` (1 `V.cons` V.zipWith (+) fib (V.tail v))

Cheers,
Edgar
Edgar Z. Alvarenga | 8 Mar 2010 00:08

Re: Recursive definition of fibonacci with Data.Vector

On Sun, 07/Mar/2010 at 17:04 -0500, Brian Sniffen wrote:
> To what do you expect 'v' to refer?

Data.Vector

> Why use 'let' for the definition?
> 
> And then once you sort it out to something like:
> 
>     fib = 0 `V.cons` (1 `V.cons` V.zipWith (+) fib (V.tail fib))

Was just a typo (the line above was copy from ghci).

> The three Vector operations used here are strict in the length of
> their arguments. So what length should 'fib' have?  2 more than its
> own length... which is more RAM than this computer has.

Ok, now I understood, is because of the strictness. The next time I 
would look in the source code first.

Thanks,
Edgar

> -Brian
> 
> On Sun, Mar 7, 2010 at 3:49 PM, Edgar Z. Alvarenga <edgar <at> ymonad.com> wrote:
> > Hello,
> >
> > why I can't define a recursive vector using Data.Vector, like in
> > the example:
> >
> > import qualified Data.Vector as V
> >
> > let fib = 0 `V.cons` (1 `V.cons` V.zipWith (+) fib (V.tail v))
> >
> > Cheers,
> > Edgar
> > _______________________________________________
> > Haskell mailing list
> > Haskell <at> haskell.org
> > http://www.haskell.org/mailman/listinfo/haskell
> >
> 
> 
> 
> -- 
> Brian Sniffen
> http://evenmere.org/~bts/
> <bts <at> evenmere.org>

Gmane