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Announce: Yi 0.3
by Jean-Philippe Bernardy 31 Jan '08

31 Jan '08

Hello folks, I'm please to announce the 0.3 release of the Yi editor. Yi is a text editor written and extensible in Haskell. The long-term goal of the Yi project is to provide the editor of choice for Haskell programmers. In the meantime, we have fun by hacking an editor in a decent language :) Yi is not a finished product: this is a developer pre-release. However, Yi has become a lot more accessible than previously, so if you consider hacking on it, now might be a good time to take a look. Features * A purely functional editor core; * Keybindings written as parsers of the input; * Emacs and Vim emulations provided by default; * Vty, Gtk2Hs?, and (experimental) Cocoa frontends; * Embedding of GHC API for quick hacks and configuration. Links * release notes: http://code.google.com/p/yi-editor/wiki/ReleaseNotes0o3 * download: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/yi-0.3 * FAQ: http://haskell.org/haskellwiki/Yi/FAQ * homepage: http://haskell.org/haskellwiki/Yi * API documentation: http://code.haskell.org/yi/doc/ * check and report issues: http://code.google.com/p/yi-editor/issues/list * darcs repository: http://code.haskell.org/yi * get involved: mailto:yi-devel@googlegroups.com This release is brought to you by: Allan Clark, Andrew Birkett, Ben Moseley, Corey O'Connor, Daniel McAllansmith, Fraser Wilson, Gustav Munkby, Gwern Branwen, Jean-Philippe Bernardy, Jens Petersen, Massimiliano Gubinelli, Michael Maloney, Nicolas Pouillard, Paulo Tanimoto, Scott Williams, Thomas Schilling.

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2008 OCaml Summer Project
by Yaron Minsky 30 Jan '08

30 Jan '08

I hope this isn't deemed too off-topic for a Haskell list, since OCaml and Haskell are close relatives on good terms. In any case: I am pleased to announce the second OCaml Summer Project! The OSP is aimed at encouraging growth in the OCaml community by funding students over the summer to work on open-source projects in OCaml. We'll fund up to three months of work, and at the end of the summer, we will fly the participants out for a meeting in New York, where people will present their projects and get a chance to meet with other members of the OCaml community. The project is being funded and run by Jane Street Capital. Jane Street makes extensive use of OCaml, and we are excited about the idea of encouraging and growing the OCaml community. Our goal this year is to get both faculty and students involved. To that end, we will require joint applications from the student or students who will be working on the project, and from a faculty member who both recommends the students and will mentor them throughout the project. Each student will receive a grant of $5k/month for over the course of the project, and each faculty member will receive $2k/month. We expect students to treat this as a full-time commitment, and for professors to spend the equivalent of one day a week on the project. We will also award a prize for what we deem to be the most successful project. Special consideration will be given to projects that display real polish in the form of good documentation, robust build systems, and effective test suites. We'll announce more details about the prize farther down the line. If you'd like to learn more about the OSP and how to apply, you can look at our website here: http://ocamlsummerproject.com Please direct any questions or suggestions you have to osp(a)janestcapital.com. y -- Yaron Minsky <yminsky(a)janestcapital.com>

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Presentations at Dutch Functional Programming Day 2008
by Johan Jeuring 30 Jan '08

30 Jan '08

Most of the presentations at the Dutch Functional Programming Day 2008 are now available on-line: http://people.cs.uu.nl/johanj/FPDag2008/ All slides are in English. -- Johan

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PhD positions in Functional Programming at Chalmers in Sweden
by Koen Claessen 30 Jan '08

30 Jan '08

(apologies for multiple copies) ** please forward this to interested students ** PhD Positions in Functional Programming at the department of Computer Science and Engineering at Chalmers University of Technology, Sweden http://www.cs.chalmers.se/~koen/phdad.html Application deadline: March 11, 2008 Position starts: April 1, 2008 or September 1, 2008 The PhD student will join the research activities at our department in applications of functional programming, much of which concentrates on the design and application of Domain Specific Embedded Languages. Examples of our work are QuickCheck for specification-guided random testing, and Lava for hardware design and verification. Our group has also developed the award winning automated first-order logic reasoning tools Paradox and Equinox, which are both written in Haskell. There are advertised positions in two focus areas: 1. Development of the next generation of Paradox and Equinox, which involves inventing new programming techniques for building a modular, flexible automated reasoning tool, as well as developing novel automated reasoning algorithms. As new exciting applications for automated reasoning tools arise, new demands are placed on the reasoning tools, forcing changes in how they are designed and implemented. 2. Development of verification techniques for distributed systems implemented in the functional programming language Erlang. Methods here include QuickCheck-based testing, model checking and (automated) theorem proving techniques, and integration of these different techniques. There is a possibility of attacking real-world problems from our industrial partners. For more information, please look at: http://www.cs.chalmers.se/~koen/phdad.html Koen Claessen John Hughes

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School LERNET 2008 *** Deadline extension for registration ***
by Alberto Pardo 29 Jan '08

29 Jan '08

=================================================================== *** DEADLINE EXTENSION FOR REGISTRATION *** Call for Participation International Summer School on Language Engineering and Rigorous Software Development LERNET 2008, Piriapolis, Uruguay February 25 to March 1, 2008 http://www.fing.edu.uy/inco/eventos/lernet2008 email: lernet(a)fing.edu.uy *** NEW DEADLINE FOR REGISTRATION: February 4 *** *** DEADLINE FOR GRANT APPLICATION: January 31 *** =================================================================== The aim of the school is the dissemination of advanced scientific knowledge and the promotion of international contacts among scientists. The school is oriented to students and researchers working in computer science and interested in formal techniques for the design and construction of software systems and programming languages. The school is partially supported by the EU LerNet ALFA project (http://www.di.uminho.pt/lernet/) which implements a joint PhD programme on Software Design and Programming Language Engineering, based on a co-tutoring scheme and conformed by 6 european universities and 5 from Latin America. PROGRAM LERNET 2008 will consist of six courses: - Introduction to Type Theory Herman Geuvers (Radboud University Nijmegen, The Netherlands) - Theory and Applications of the PF-transform Jose Nuno Oliveira (University of Minho, Portugal) - Embedded Domain Specific Languages: Combinator Parsers Doaitse Swierstra (Utrecht University, The Netherlands) - Dependent Types at Work Peter Dybjer and Ana Bove (Chalmers University, Sweden) - Formal Programming Language Semantics with Inductive Types Yves Bertot (INRIA Sophia-Antipolis, France) - Verification Methods for Software Security and Correctness Gilles Barthe (INRIA Sophia-Antipolis, France) In addition, there will be some PhD sessions where students from the LerNet project will expose advances of their PhD thesis. VENUE LERNET 2008 will be held at Argentino Hotel (http://www.argentinohotel.com.uy) located in Piriápolis, a seaside city, 100 kms east from Montevideo. REGISTRATION To register, fill in the registration form at http://www.cs.chalmers.se/Cs/Research/Logic/LerNet08/registration.html The deadline for registration has been *extended*. The new deadline is February 4, 2008. FEES Details about the registration fees can be found in the school's webpage (http://www.fing.edu.uy/inco/eventos/lernet2008) GRANTS We may be able to offer a reduction in the value of the registration fee to a limited number of students. Priority will be given to students from Latin America. Details of the fee reduction application can be found in the school's webpage (http://www.fing.edu.uy/inco/eventos/lernet2008) The deadline for grant application is January, 31 2008. **Note that this deadline has not been extended**. SCHOOL ORGANISERS Luis Barbosa (Univerity of Minho, Portugal) Ana Bove (Chalmers University, Sweden) Alberto Pardo (Universidad de la República, Uruguay) Jorge Sousa Pinto (Univerity of Minho, Portugal) LOCAL ORGANISATION Alberto Pardo Luis Sierra Carlos Luna Instituto de Computación Facultad de Ingeniería Universidad de la República Montevideo, Uruguay FURTHER INFORMATION For further details on the school, visit the webpage http://www.fing.edu.uy/inco/eventos/lernet2008

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4th Haskell Hackathon, April 11-13 in Gothenburg, Sweden
by Björn Bringert 28 Jan '08

28 Jan '08

------------------------------------------------------------------------ Hac4 4th Haskell Hackathon April 11-13, 2008 Gothenburg, Sweden http://haskell.org/haskellwiki/Hac4 ------------------------------------------------------------------------ We are pleased to announce the 4th Haskell Hackathon! The event will be held over 3 days, April 11-13, at Chalmers University of Technology in Gothenburg, Sweden. The plan is to hack on Haskell infrastructure, tools, libraries and compilers. To attend please register, and get ready to hack those lambdas! Code to hack on: * Hackage * Cabal * Porting foreign libraries * Bug squashing * You decide! Before you attend, do start thinking and familiarizing yourself with 1 or 2 projects you wish to work on, to ensure no wasted effort during the Hackathon. A list of possible projects is available on the website. == Registration == We ask that you register you interest. Follow the instructions on the registration page: http://haskell.org/haskellwiki/Hac4/Register Once you've registered, do add your info to the attendees self-organizing page, http://haskell.org/haskellwiki/Hac4/Attendees if you are looking to share costs, or meet up prior to the hackathon, with other attendees. N.B. if you already expressed interest via the wiki, do confirm by registering `officially' anyway. == Important dates == Hackathon: April 11-13, 2008 == Organizers == Björn Bringert Thomas Schilling Lennart Kolmodin

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ANNOUNCE: HStringTemplate -- An Elegant, Functional, Nifty Templating Engine for Haskell
by Sterling Clover 27 Jan '08

27 Jan '08

HStringTemplate is a port of Terrence Parr’s lovely StringTemplate (http://www.stringtemplate.org) engine to Haskell. It is available, cabalized, at: darcs get http://code.haskell.org/HStringTemplate/ As interest has grown in using Haskell for web applications, there has been an increasing buzz about the need for a good templating engine in Haskell. Why might we need this? After all, Haskell has lovely combinator libraries for generating HTML programmatically, enforcing good form through its type system. But sometimes, we don’t want well-formed HTML. We want the ugly stuff that floats around to deal with eight varieties of browser incompatibilities and the latest silly ajax trick. Or sometimes we’re working with a team of graphic designers, and they want to work in almost-HTML. Or sometimes we just want to be able to change the design of a web application on the fly, completely independent of our program logic, and of, heavens forbid, recompiling and possibly messing with a live application. So template engines are popular, and indeed, considered a key part of most web frameworks out there. One problem — they’re mainly awful, imperatively-conceived behemoths that capriciously mix program logic with display and, consequently, entail a great deal of overhead. Enter StringTemplate, a nifty and fairly-well developed template format that’s both pure and functional, and therefore pretty much the only one of its kind. Indeed, it also seems to be getting heavy use in code generation because its paradigm maps neatly to traversing parse-trees. HStringTemplate is not feature-complete, and indeed is only at version 0.1. But it should implement pretty much everything in the standard StringTemplate 3.0 grammar, only nicer, because it’s in Haskell. There are scads of different recursive constructs and ways to handle inclusion and inheritance. Furthermore, HStringTemplate handles conditionals, and sports also a very Haskellish implementation of custom rendering. Templates can be constructed that return strings, ShowSs, bytestrings, or even pretty printer Docs that handle wrapping, indentation, and fill elegantly. Even better, these templates are parsed and compiled only once, after which point there isn't a syntax tree anymore, just a function that operates on the environment of attributes that have been passed to it. Where I take it from here depends in part on what sort of response I get, so patches, gripes, API comments and feature requests are all more than welcome. Please note that I'm still working in 6.6.1. Everything should be in place to compile properly with the base split, but if it isn't, again, patches more than welcome. Full announcement at: http://fmapfixreturn.wordpress.com/ --SC

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Re: [Haskell-cafe] Why functional programming matters
by Michael Reid 25 Jan '08

25 Jan '08

Yaakov Nemoy wrote: > I'm still very much a newbie, but the one thing that struck me as the > best feature coming from Python is the static typing. Changing the > type of a function in Python will lead to strange runtime errors that > take some work to debug, whereas, when I tinker with a program in > Haskell, I already know it will work once it compiles. > I'm quite new to Haskell as well and I must echo this sentiment. The mainstream has somewhat realized that its a waste of time to tell the compiler the type of _everything_. Learning Haskell has completely reversed my feeling that static typing is an old outdated idea. The power of Haskell's type system makes it feel like you are programming in a dynamic language to some degree, yet all of it is type-checked, and that is just *really* cool. Honestly, when I first started reading a Haskell tutorial I was convinced that it was an runtime-typed language like Python. When the tutorial moved on to explain that it is statically typed I could barely believe it. The second thing I might want to highlight is the power of monads and other techniques like arrows and FRP. Granted, these are not easy concepts to impart in a talk, but I think they were really an important discovery in FP as they deal with the "problem" of IO in such a beautifully orthogonal way. Following on that, more advanced structures like arrows and how all of this can contribute to really powerful DSLs I think is a pretty big selling point. Actually, come to think of it, one great way to show off the language is to show off the power of some of the libraries that have been written. For example, show how easily a parser can be created w/ Parsec; or show an example of FRP w/ Yampa. These examples will likely tantalize the programmers in the audience to want to learn more. Good luck! /mike.

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Why functional programming matters
by Simon Peyton-Jones 23 Jan '08

23 Jan '08

Friends Over the next few months I'm giving two or three talks to groups of *non* functional programmers about why functional programming is interesting and important. If you like, it's the same general goal as John Hughes's famous paper "Why functional programming matters". Audience: some are technical managers, some are professional programmers; but my base assumption is that none already know anything much about functional programming. Now, I can easily rant on about the glories of functional programming, but I'm a biased witness -- I've been doing this stuff too long. So this message is ask your help, especially if you are someone who has a somewhat-recent recollection of realising "wow, this fp stuff is so cool/useful/powerful/etc". I'm going to say some general things, of course, about purity and effects, modularity, types, testing, reasoning, parallelism and so on. But I hate general waffle, so I want to give concrete evidence, and that is what I particularly want your help with. I'm thinking of two sorts of "evidence": 1. Small examples of actual code. The goal here is (a) to convey a visceral idea of what functional programming *is*, rather than just assume the audience knows (they don't), and (b) to convey an idea of why it might be good. One of my favourite examples is quicksort, for reasons explained here: http://haskell.org/haskellwiki/Introduction#What.27s_good_about_functional_… But I'm sure that you each have a personal favourite or two. Would you like to send them to me, along with a paragraph or two about why you found it compelling? For this purpose, a dozen lines of code or so is probably a maximum. 2. War stories from real life. eg "In company X in 2004 they rewrote their application in Haskell/Caml with result Y". Again, for my purpose I can't tell very long stories; but your message can give a bit more detail than one might actually give in a presentation. The more concrete and specific, the better. E.g. what, exactly, about using a functional language made it a win for you? If you just reply to me, with evidence of either kind, I'll glue it together (regardless of whether I find I can use it in my talks), and put the result on a Wiki page somewhere. In both cases pointers to blog entries are fine. Quite a lot of this is FP-ish rather than Haskell-ish, but I'm consulting the Haskell mailing lists first because I think you'll give me plenty to go on; and because at least one of the talks *is* Haskell-specific. However, feel free to reply in F# or Caml if that's easier for you. Thanks! Simon

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ANNOUNCE: Harpy 0.4 - Runtime code generation for x86 machine code
by Martin Grabmueller 23 Jan '08

23 Jan '08

We are pleased to announce the release of Harpy 0.4, a library for runtime code generation for x86 machine code. Harpy is available from Hackage: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/harpy-0.4 Also see Harpy's homepage, which features two tutorials and access to the darcs repo (and to the Haddock documentation, until it is available from Hackage, too): http://uebb.cs.tu-berlin.de/harpy/ Harpy is supposed to be built with GHC 6.8 and GHC 6.6 (with Cabal 1.2 or greater). Please report any build problems you encounter. This release features the following additions and fixes: - New convenience top-level module "Harpy", which re-exports Harpy.CodeGenMonad, Harpy.Call and Harpy.X86Assembler - It is now possible to override Harpy's automatic code buffer management. The new field 'customCodeBuffer' in the type 'CodeGenConfig' can be set to 'Just (buf, size)', where 'buf' is a pointer to a memory region of 'size' bytes. Harpy will then use the supplied code buffer and will not perform any automatic code buffer allocation on overflow. Overflow checking is still performed and will result in an exception in the CodeGen monad. - When using the high-level assembler in X86Assembler, the code buffer is automatically protected from overflow. - Floating point operations added to X86Assembler (only for double operands yet). - Preliminary support for SSE instructions. Currently, only the packed and scalar floating-point arithmetic operations are supported (both in the low-level module Harpy.X86CodeGen and as methods in Harpy.X86Assembler) - Code buffer default size has been increased from 128 to 4096 bytes. - The CodeGenMonad fails when a label is defined twice. - It is now possible to associate names with labels, using the new operation newNamedLabel. The given names will show up in the disassembly, which makes debugging of generated code much easier. - The doc directory contains a second, slightly larger tutorial now. - The examples/evaluator directory contains a small example interpreter for arithmetic expressions, which translates expressions entered at the keayboard to machine code on the fly. This is the demo program we presented at the Haskell Workshop 2007. Happy Haskell Hacking with Harpy, Martin and Dirk

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