February 2003 - Haskell

Re: seeking ideas for short lecture on type classes
by Norman Ramsey 04 Feb '03

04 Feb '03

> > In a fit of madness, I have agreed to deliver a 50-minute lecture > > on type classes to an audience of undergraduate students. These > > students will have seen some simple typing rules for F2 and will > > have some exposure to Hindley-Milner type inference in the context > > of ML. > > Will they have had exposure to more "traditional" OO programming? If > so, it might be useful to note the difference between Haskell type > classes and C++/Java/whatever classes, namely that Haskell decouples > types and the interfaces that they support. The advantage is that you > can extend a type with a new interface at any point, not just when you > define the type. Hmm --- you are talking about the `instance' declarations, right? A fact that I know but don't understand the implication of is that Haskell dispatches on the static type of a value, whereas OO languages dispatch on the dynamic type of a value. But I suspect I'll leave that out :-) N

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Re: [OT] Teaching Haskell in High School (fwd)
by Rex Page 04 Feb '03

04 Feb '03

This matches my experience, too. When I've taught Haskell to first year college students, there have always been some hard core hackers who've been at it in C or VB or Perl or something like that for years, and they rarely take kindly to Haskell. The ones without any programming background do better. I think Haskell would be great for a high school math class. They could learn some logic and induction along with it, and get a few proofs back into the high school math curriculum. Rex Page ---------- Forwarded message ---------- Date: Tue, 04 Feb 2003 03:03:03 +0100 From: Wolfgang Jeltsch <wolfgang(a)jeltsch.net> To: The Haskell Mailing List <haskell(a)haskell.org> Subject: Re: [OT] Teaching Haskell in High School On Tuesday, 2003-02-04, 01:01, CET, Hal Daume wrote: > [...] > However, I'm also well aware that Haskell is very difficult to learn (and, > I'd imagine, to teach). Hi, I wouldn't claim that Haskell is very difficult to learn. I think, people often have problems with learning Haskell because they know imperative programming and try to apply their imperative thinking to programming in Haskell. Some months ago, a first year student told me that she liked Haskell very much and that she didn't find it very difficult. I asked her if she had had experiences with other programming languages before learning Haskell. She answered: "No." > [...] Wolfgang _______________________________________________ Haskell mailing list Haskell(a)haskell.org http://www.haskell.org/mailman/listinfo/haskell

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RE: [OT] Teaching Haskell in High School
by Simon Peyton-Jones 04 Feb '03

04 Feb '03

Don't forget Helium (recently announced) http://www.cs.uu.nl/~afie/helium/index.html Also Manuel Chakravarty teaches Haskell to hordes. Simon | -----Original Message----- | From: Hal Daume III [mailto:hdaume@ISI.EDU] | Sent: 04 February 2003 00:02 | To: Haskell Mailing List | Subject: [OT] Teaching Haskell in High School | | Hi all, | | Before getting in to this, let me preface my question(s) with a note that | I have checked through the Haskell in Education web page and have found | various links off there of interest (and I've googled, etc. In | short: I've done my homework). | | That said, I've been in rather close correspondence with my math/computer | science teacher from high school. When I first took CS there, they taught | Pascal (a year early they had been teaching Scheme). They switched over | to VB (alas) recently and have been teaching that for a few years now. | | The teacher really wants to get away from VB, but is having a somewhat | difficult time deciding what to go to. The two most promising options are | Haskell and Java. | | Aside from hype, etc., the primary advantage to Java is that the Advanced | Placement (AP) tests are in Java. For those of you unfamiliar with these, | high school students can take AP tests and then (typically) skip out of | first semester college courses. They're essentially proficiency exams. | | The way the computer science curriculum is set up at my old school is | essentially as either (a) an elective or (b) a replacement for senior year | math. The students in the course are usually about 2/3 juniors (16 year | olds) taking it as an elective and 1/3 seniors who want to get our of | senior year math :). Either way, they've both taken differential | calculus, algebra, etc. Note, however, that high school math in the | states is very rudimentary when it comes to things like "induction" and | "proofs" and things of this sort. | | Due to the fact that CS is essentially an alternative math course, I think | it would be interesting to teach Haskell. It would enable the instruction | of things the students wouldn't have come across in their ordinary math | studies, etc. | | However, I'm also well aware that Haskell is very difficult to learn (and, | I'd imagine, to teach). Given that this would in large part be a first | language for them and that they won't have a college-level math | background, do you think it would be too much to attempt to teach Haskell | at this level, and stick with Java? | | I'm really interested in any comments/experience/etc. that people have | that might assist the teacher (and, to some extent, me) make this | decision. | | Thanks in advance! | | - Hal | | | _______________________________________________ | Haskell mailing list | Haskell(a)haskell.org | http://www.haskell.org/mailman/listinfo/haskell

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PLC 27: call for participation
by Sophia A. Malamud 04 Feb '03

04 Feb '03

Dear friends and colleagues, Please circulate this announcement and call for registration! We apologise for multiple mailings. ________________________________________________________________________ 27th Penn Linguistics Colloquium ________________________________________________________________________ The 27th Annual Penn Linguistics Colloquium is scheduled for Friday through Sunday, February 21 through 23, 2003 at the University of Pennsylvania campus in Philadelphia. Keynote Lecture: A Compositional Characterization of the Definiteness Effect in Existential-There Sentences Invited Speaker: Professor Edward Keenan of UCLA Panel Discussion: Goffmans Legacy and Future Study of Language Interaction Discussants include: Deborah Shiffrin, William Labov Our program includes sessions on language acquisition, syntax, mathematical linguistics, sociolinguistics, historical linguistics, phonology, pragmatics, psycholinguistics, as well as a Special Session in formal semantics. Schedule of talks and local information are available at the conference website: http://www.ling.upenn.edu/Events/PLC/ ***Online pre-registration form is available now and until February 15th *** at http://www.ling.upenn.edu/Events/PLC/registration/register.php The pre-registration fee is $20 (students $15), on-site registration is $23 (students $18). Please pre-register! Early registration will help us estimate the number of attendees, and help you avoid paying extra $3 for on-site registration. If you have questions or concerns, please contact us at one of the following addresses: The Penn Linguistics Colloquium Committee Department of Linguistics 619 Williams Hall University of Pennsylvania Philadelphia, PA 19104-6305 plc27(a)ling.upenn.edu http://www.ling.upenn.edu/Events/PLC This event is supported by funding from GSAC, the Graduate Student Association Council of University of Pennsylvania. ________________________________________________________________________

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RE: time since the epoch
by George Russell 03 Feb '03

03 Feb '03

Simon PJ wrote (snipped) > Meanwhile, I suspect there's an opportunity for someone (or a small > group) to suggest a new Time library that really does the business, and > provide an implementation. If it's sufficiently persuasive, all the > implementations will adopt it and it can become a de-facto standard. I already have written a TimeExts library which is in fact bundled with GHC, namely in -package lang. What I ought to do, I suppose, is fishify the comments so Haddock can produce something useful. Basically it allows you to add a time difference to a ClockTime value to get another ClockTime value, or subtract two ClockTime values to get a time difference. The time difference can be a number of picoseconds, seconds, minutes, hours, days, months or years. For all but seconds and picoseconds, it does this by converting to CalendarTime (using toUTCTime), doing complicated Gregorian calendar calculations (I am not proud of the code here), and then converting back using toClockTime. This is probably not a very good way of doing it but at least no-one has complained about it so far. Which means either it's perfect or no-one uses it, I fear the latter. At least it might be a good idea to start with something like this code, rather than reinventing the wheel. Things you need to watch out for are (a) leap seconds; (b) time zones. I didn't really address the time zone problem, instead doing everything in UTC. For us Europeans, it doesn't normally make any difference whether you use local or UTC time when you ask for the date one month from now.

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Haskell Workshop 2003
by Johan Jeuring 03 Feb '03

03 Feb '03

ACM SIGPLAN 2003 Haskell Workshop Uppsala, Sweden, End of August 2003 pending approval http://www.functional-programming.org/HaskellWorkshop/cfp03.html Call For Papers The Haskell Workshop forms part of the PLI 2003 colloquium on Principles, Logics, and Implementations of high-level programming languages, which comprises the ICFP and PPDP conferences as well as associated workshops. Previous Haskell Workshops have been held in La Jolla (1995), Amsterdam (1997), Paris (1999), Montreal (2000), Firenze (2001), and Pittsburgh (2002). ********************* Deadlines ********************* Deadline for submission: May 22, 2003 Notification of acceptance: June 23, 2003 Final submission due: July 3, 2003 Haskell Workshop: End of August 2003 ********************* Topics ********************* The purpose of the Haskell Workshop is to discuss experience with Haskell, and possible future developments for the language. The scope of the workshop includes all aspects of the design, semantics, theory, application, implementation, and teaching of Haskell. Topics of interest include, but are not limited to, the following: Language Design with a focus on possible extensions and modifications of Haskell as well as critical discussions of the status quo; Theory in the form of a formal treatment of the semantics of the present language or future extensions, type systems, and foundations for program analysis and transformation; Implementation Techniques including program analysis and transformation, static and dynamic compilation for sequential, parallel, and distributed architectures, memory management as well as foreign function and component interfaces; Tool Support in the form of profilers, tracers, debuggers, pre-processors, and so forth; Applications, Practice, and Experience with Haskell for scientific and symbolic computing, database, multimedia and Web applications, and so forth as well as general experience with Haskell in education and industry; Functional Pearls being elegant, instructive examples of using Haskell. Following the scheme adopted by ICFP 2003, papers in the latter two categories need not necessarily report original research results; they may instead, for example, report practical experience that will be useful to others, re-usable programming idioms, or elegant new ways of approaching a problem. The key criterion for such a paper is that it makes a contribution from which other practitioners can benefit. It is not enough simply to describe a program! ********************* Submissions ********************* Authors should submit papers in postscript format, formatted for A4 paper, to Johan Jeuring johanj(a)cs.uu.nl by 22th May 2003. The length should be restricted to the equivalent of 5000 words (which is approximately 12 pages in ACM format). Accepted papers will be available in the form of a technical report of the Utrecht University or an equivalent format in time for the workshop. In addition, the papers will be published by the ACM and will appear in the ACM Digital Library. If there is sufficient demand, we will try to organise facilities for system demonstrations during lunch and coffee breaks. If you are interested in demonstrating an application or tool written in Haskell, please contact Johan Jeuring (johanj(a)cs.uu.nl) ********************* Programme Committee ********************* Magnus Carlsson OGI Olaf Chitil University of York Ralf Hinze University of Bonn Johan Jeuring (chair) Utrecht University Jan-Willem Maessen MIT Henrik Nilsson Yale University Simon Peyton Jones Microsoft Research Claus Reinke University of Kent

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ANNOUNCE: Helium, for learning Haskell
by Arjan van IJzendoorn 03 Feb '03

03 Feb '03

=================================== Helium (for learning Haskell) 1.0 =================================== We are pleased to announce the first public release of the Helium system, consisting of a language, compiler and interpreter designed especially for education in functional programming. It is being developed at the Software Technology group of the Institute of Information and Computing Sciences of Utrecht University in the Netherlands. CURRENT RELEASE The language is a (large) subset of Haskell 98. Most notable difference is the absence of type classes. Without type classes, types are simpler and more specific type errors can be given. The compiler gives high-quality error messages with exact locations and sometimes hints (e.g. in the case of misspelled names). Warnings are given for unused parameters, shadowing and more. The most sophisticated part is the type checker which uses a novel constraint-based inferencer to improve type error messages. The compiler generates portable byte codes for the Lazy Virtual Machine (cf. JVM for Java) resulting in a system that is a magnitude faster than Hugs. The Helium interpreter "Hi" is a Hugs-like application which is built on top of the compiler. Together these features make Helium a fine tool for teaching environments. We have experienced that friendlier compiler messages make learning functional programming more fun for our students. More information and downloads can be found at the Helium homepage: http://www.cs.uu.nl/~afie/helium/index.html FUTURE ENHANCEMENTS - User manuals for the different tools - (Closed world) type classes - A more visually pleasing and powerful interpreter - More libraries (e.g. GUI) - Binary distributions for more platforms With kind regards, the Helium team

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EUROLAN-2003 Summer School - First call for participation
by Dan Cristea 02 Feb '03

02 Feb '03

Dear Colleagues, Could you, please, distribute the enclosed information on the EUROLAN-2003 Summer School on "Semantic Web and Language Technology" to persons that can be potentially interested (students, graduate students, young faculty, researchers, etc.). Please excuse multiple copies of this message. Thank you, Dan Cristea ---------------------------------------------------------------------------------- EUROLAN-2003 Summer School on "The Semantic Web and Language Technology - Its Potential and Practicalities" 28 July - 8 August 2003 Bucharest - Romania http://www.infoiasi.ro/~eurolan/eurolan2003 - First Call For Participation - The Eurolan series of summer schools was established in 1993 and has been held every other year, with the goal of stimulating young researchers from all over the world to pursue high-level research in natural language processing and language technology. Theme The fifth EUROLAN in the series will have as topic all aspects of the developing Semantic Web technology and consider its potential and the practicalities of applying it to enhance language processing applications. The promise of the Semantic Web has evoked enormous interest within the community developing language technologies. On the one hand, it offers the potential to exploit ontological descriptions of language data in order to enable inferencing capabilities, which may not only drastically enhance semantic processing, but also alter our conceptions of the ways in which knowledge is represented and exploited in language processing applications. On the other hand, to take full advantage of this evolving technology, researchers and developers will need to understand the potential as well as the limitations of the Semantic Web and master a range of new technologies that have been designed to enable it. Finally, the language technology community must be ready to contribute to Semantic Web development in order to ensure that it meets the requirements for language processing applications. The so-called "Semantic Web community" encompasses several research communities that have previously worked independently of one another, including researchers in knowledge representation, ontology development, and "knowledge exploitation"; web developers (including developers of standards such as XML, RDF, OWL, etc.); and those who directly need to exploit knowledge in applications. Linguistic knowledge used in language processing at its various levels (morphological, syntactic, lexical, discourse, etc.) includes a substantial part of general knowledge and poses a significant challenge to Semantic Web developers in order to handle the precision and complexity required for language processing applications. Whatever the Semantic Web may evolve to be, researchers and developers in language technology clearly need to learn what it is and how it can be exploited for language processing, and at the same time, work with semantic web developers to ensure that the semantic web infrastructure is maximally usable for language processing applications. EUROLAN-2003 will provide two weeks of intensive study of semantic web technology and its application to natural language processing. Internationally known scholars and researchers involved in leading-edge work in relevant areas will serve as professors at the school, providing half- and full-day seminars and hands-on labs to provide students with in-depth understanding and experience. Topics to be covered in the school include the following: * What is the Semantic Web? * Potential and limitations of the semantic web * Supporting web technologies (XML, RDF) * Ontologies, ontology design and development * Ontology exploitation via inferencing * Description logics and other approaches to inferencing * Lexical semantics and the semantic web * Use of the semantic web and related technologies in language processing applications The list of invited personalities is as follows: * Dan Cristea, "Al. I. Cuza" University of Iasi, Romania * Thierry Declerck, DFKI Saarbruecken, Germany * James Hendler, University of Maryland at College Park, USA * Jerry Hobbs, University of Southern California, Marina del Rey, USA * Nancy Ide, Vassar College, USA * Alessandro Lenci, University of Pisa, Italy * Robert Meersman, Vrije Universiteit, Brussel, Belgium * Srini Narayanan, SRI-International, Menlo Park, SUA * Sergei Nirenburg, New Mexico University, USA * Dan Tufis, Romanian Academy, Bucharest, Romania * Hans Uszkoreit, DFKI and University of Saarbruecken, Germany * Wolfgang Wahlster, DFKI and University of Saarbruecken, Germany * Yorick Wilks, University of Sheffield, England Program Eurolan-2003 will take place between 28 July and 8 August 2003 in Bucharest - Romania. The summer school will be organized to allow for both lectures and hands-on experience for each of the areas covered. Morning sessions will be devoted to tutorials, followed by afternoon sessions at which students will work in collaboration with professors on practical applications. The school will also include one workshop as well as round tables and work meetings on topics of particular interest related to the school’s theme. They will be announced at a later date. On Sunday, 3 August, a trip to significant Romanian landmarks will be organized. Registration and Fees Information about registration and fees will be posted at a later date. Program Committee Dan Cristea Nancy Ide Jerry Hobbs Dan Tufis Hans Uszkoreit Information on previous Eurolan events can be consulted at the address: http://www.infoiasi.ro/fcs/en/events.html.

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International Symposium on Information and Communication Technologies
by International Symposium on Information and Communication Technologies 01 Feb '03

01 Feb '03

This is a one time only posting. Apologies if you receive unwanted or multiple copies of this message. Call for Workshops / Call for Papers ISICT 03 International Symposium on Information and Communication Technologies Trinity College Dublin, Ireland September 24-26, 2003 The purpose of ISICT 03 is to provide an international forum for discussion between theoreticians and practitioners and to promote an inter disciplinary exchange of research ideas. We invite papers exploring all aspects of Computer and Communication Technologies. Topics of interest include, but are not limited to: * Computer Science * Information Technology and Systems * Communication Technology * Networks, Control Systems * Image, Acoustic, Speech and Signal Processing * Experience and Applications There are two principal modes of paper submission: MODE I : Invited Workshop Organization To chair and organize a workshop at ISICT03 send an email to workshops(a)isict.org with the title, a description of the topic of your proposed workshop up to two hundred words in length, and the name(s) of the workshop organizer(s) and chair(s) as soon as possible and before 1st June 2003. If your proposal is suitable, you will receive preliminary approval notification within a few days. Final approval will depend upon submission and registration of at least FOUR papers in the workshop by the ISICT03 camera ready deadline of 1st July 2003. The organizer(s) of pre-approved workshops will be responsible for advertising their workshop, using electronic or other means, and for the reviewing process for their workshop's papers or extended abstracts, and for the notification to ISICT03 of accepted papers. The organizer(s) of approved workshops will be added to the ISICT03 programme committee and be editors of the ISICT03 conference proceedings. MODE II : Stand-Alone Papers Papers should be submitted in PDF format by e-mail to submissions(a)isict.org by 1st May 2003 for review. Please submit either an extended abstract or short paper of up to 6 pages in length. Papers should be formatted so that they are single-spaced, single column, and use a 12pt Times font. Include title, author list, postal address and abstract as plain text in the e-mail. All papers submitted will be reviewed in full by reviewers from independent institutions. Important Dates 1st May 2003 Submission of stand-alone papers 1st June 2003 Notification of acceptance of stand-alone papers 1st June 2003 Preliminary approval of invited workshops 1st July 2003 Camera-ready copies due for all papers 1st July 2003 Registration due for all papers 24-26th September 2003 Conference The Venue In comparison to other capitals, Dublin is a convivial city with a human scale and an extroverted populace. At the heart of the city lies Trinity College with its magnificent buildings and beautiful campus spanning 35 acres. Trinity College has occupied this location for the past 400 years, and while none of the original buildings remain, the College boasts fine squares and gardens and a collection of magnificent buildings dating from the 17th to the 20th century. In contrast to the serene surroundings of the College landscape, the modern city of Dublin is just outside the main gate of the campus, with shops, theatres, cinemas and museums within walking distance. Contact Address ISICT 03, Department of Computer Science, O'Reilly Institute, Trinity College, Dublin 2, Ireland. Please email general queries to info(a)isict.org URL: http://www.isict.org

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