[Haskell-cafe] PPDP'13: Last call for papers

University Potsdam, Germany Tom Schrijvers Ghent University, Belgium Martin SulzmannHochschule Karlsruhe, Germany Wouter Swierstra Universiteit Utrecht, The Netherlands Tarmo Uustalu Institute of Cybernetics, Estonia Janis Voigtlaender

[Haskell-cafe] PPDP 2013: 2nd Call for Papers

University of Porto, Portugal Torsten Schaub University Potsdam, Germany Tom Schrijvers Ghent University, Belgium Martin SulzmannHochschule Karlsruhe, Germany Wouter Swierstra Universiteit Utrecht, The Netherlands Tarmo Uustalu Institute

[Haskell-cafe] PPDP 2013: Call for Papers

Chalmers University of Technology, Sweden Jan Wielemaker Universiteit van Amsterdam, The Netherlands Program Chair Tom Schrijvers Department of Applied Mathematics and Computer Science Ghent University 9000 Gent, Belgium General Chair Ricardo Pena

[Haskell-cafe] PhD position at Ghent University

under the direction of Tom Schrijvers. The successful applicant has a master degree in Computer Science or equivalent. Ideally, she/he will also have a strong, documented interest in doing research. Strong problem-solving and programming skills are essential. Prior knowledge of purely functional

[Haskell-cafe] FLOPS 2012: final call for papers deadline extension

user interfaces, Internet applications, XML, databases, formal methods and model checking. The proceedings will be published as an LNCS volume. The proceedings of the previous meeting (FLOPS 2010) were published as LNCS 6009. PC co-Chairs - Tom Schrijvers (Ghent

[Haskell-cafe] FLOPS 2012: 2nd call for papers

-- prof. dr. ir. Tom Schrijvers Programming Languages Group Department of Applied Mathematics and Computer Science University of Ghent Krijgslaan 281 S9 9000 Gent Belgium Phone: +32 9 264 4805 http://users.ugent.be/~tschrijv/ ___ Haskell-Cafe mailing

[Haskell-cafe] FLOPS 2012: 2nd call for papers

applications, XML, databases, formal methods and model checking. The proceedings will be published as an LNCS volume. The proceedings of the previous meeting (FLOPS 2010) were published as LNCS 6009. PC co-Chairs - Tom Schrijvers (Ghent University, Belgium) - Peter Thiemann

[Haskell-cafe] FLOPS 2012: 1st Call for Papers

interfaces, Internet applications, XML, databases, formal methods and model checking. The proceedings will be published as an LNCS volume. The proceedings of the previous meeting (FLOPS 2010) were published as LNCS 6009. PC co-Chairs - Tom Schrijvers (Ghent University, Belgium

Re: [Haskell-cafe] Strong version of 'local' for reader monad

On Mon, Dec 13, 2010 at 9:30 PM, Brent Yorgey byor...@seas.upenn.eduwrote: Hi all, Today I wanted this function strongLocal :: (MonadReader r1 m1, MonadReader r2 m2) = (r2 - r1) - m1 a - m2 a Of course, after staring at this type for ten seconds I realized that it cannot

Re: [Haskell-cafe] more thoughts on Finally tagless

Yeah, subject Finally Tagless again, sorry, I'm just not done with it yet. In Olegs haskell implementation he is using classes mainly to model the syntax and instances to use for evaluators / compilers to allow multiple interpretations. I wonder if it'd be possible to do the same without

Re: [Haskell-cafe] Restrictions on associated types for classes

-- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: tom.schrijv...@cs.kuleuven.be url: http://www.cs.kuleuven.be/~toms/ Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm

[Haskell-cafe] university courses on type families/GADTs?

Hello Haskell Cafe, I was wondering whether there are any universities that teach about Haskell type families or GADTs? Thanks, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: tom.schrijv

Re: [Haskell-cafe] Monad transformer to consume a list

list? Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: tom.schrijv...@cs.kuleuven.be url: http://www.cs.kuleuven.be/~toms/ ___ Haskell-Cafe mailing list Haskell

Re: [Haskell-cafe] Type Family Relations

___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: tom.schrijv...@cs.kuleuven.be url: http

Re: [Haskell-cafe] FunDeps vs. Associated Types

but not functional dependencies. -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] url: http://www.cs.kuleuven.be/~toms/ ___ Haskell-Cafe mailing list Haskell-Cafe

Re: [Haskell-cafe] Re: Hmm, what license to use?

Don thinking that compiler developer fragmentation doesn't help now the language research is 'done' Language researchers should move to a new language? Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail

Re: [Haskell-cafe] looking for examples of non-full Functional Dependencies

of a closed world. That's contrary to the open world view of regular type classes. So these aren't the intended semantics. Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] url: http

Re: [Haskell-cafe] looking for examples of non-full Functional Dependencies

On Fri, 25 Apr 2008, Hans Aberg wrote: On 25 Apr 2008, at 14:20, Tom Schrijvers wrote: Prolog works under the assumption of a closed world. That's contrary to the open world view of regular type classes. So these aren't the intended semantics. By which I gather you mean the interpretation

Re: [Haskell-cafe] looking for examples of non-full Functional Dependencies

hackageDB has a substantial sample of code these days, which is handy for questions like this. Thanks, Ross. These examples are perfect! Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL

Re: [Haskell-cafe] looking for examples ofnon-fullFunctional Dependencies

strange, because there is no alternative for y (except if you allow overlapping instances and add e.g. an instance C [a] [b] [Int]). Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL

[Haskell-cafe] looking for examples of non-full Functional Dependencies

| a - b has a non-full functional dependency a - b which does not involve c. Thanks, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] url: http://www.cs.kuleuven.be/~toms

Re: [Haskell-cafe] Re: type families and type signatures

String = .. type instance Id Int= .. .. But in a degenerate case there could be just this one instance: type instance Id x = GADT x which then reduces this example to the GADT case of which you said that is was clearly parametric. Tom -- Tom Schrijvers Department of Computer

Re: [Haskell-cafe] Re: type families and type signatures

, is it? Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] url: http://www.cs.kuleuven.be/~toms/ ___ Haskell-Cafe mailing list Haskell-Cafe

Re: [Haskell-cafe] Re: type families and type signatures

in the design space. Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] url: http://www.cs.kuleuven.be/~toms/ ___ Haskell-Cafe mailing

Re: [Haskell-cafe] Re: type families and type signatures

, Mark Tom Schrijvers wrote: type instance Id Int = Int foo :: Id a - Id a foo = id foo' :: Id a - Id a foo' = foo Is this expected? Yes, unfortunately, this is expected, although it is very unintuitive. This is for the following reason. Huh? This sounds very wrong to me, simply because foo

Re: [Haskell-cafe] Wumpus World

not the fastest, just like GCC doesn't generates the fastest code. Who cares? If you want speed, then Yap is the best open Prolog system. http://www.ncc.up.pt/~vsc/Yap/ Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium

Re: [Haskell-cafe] Equality constraints in type families

can properly focus on this issue and consider different design choices. Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] url: http://www.cs.kuleuven.be/~toms

Re: [Haskell-cafe] Equality constraints in type families

them if they are too confusing. Do you think there might be a definition that would satisfy me both Functor instances and equality? Thanks for your pacience, hugo -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e

Re: [Haskell-cafe] Equality constraints in type families

? Are they such that F d c ~ F a (c,a) can hold? By the way, for your function, you don't need equations in your type signature. This will do: hyloPara :: Functor (F d) = d - (F d c - c) - (a - F d a) - a - c Cheers, Tom -- Tom Schrijvers

Re: [Haskell-cafe] Equality constraints in type families

d) and Functor (F a) in the signature. Which implementation of fmap do you want? Or should they be both the same (i.e. F d ~ F a)? Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED

[Haskell-cafe] Re: Small displeasure with associated type synonyms

. We can't have that in a deterministic functional language. Hence the error. Adding a type signature doesn't change the matter. Providing an additional argument, as you propose, resolves the ambiguity. I hope this helps. Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U

Re: [Haskell-cafe] Re: Small displeasure with associated type synonyms

another point in the design space here. Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] url: http://www.cs.kuleuven.be/~toms/ ___ Haskell-Cafe

Re: [Haskell-cafe] Re: Small displeasure with associated type synonyms

: forall a b . T a = T b = a = b Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] url: http://www.cs.kuleuven.be/~toms/ ___ Haskell

[Haskell-cafe] SingHaskell 2007, November 28 2007

We're pleased to invite you to SingHaskell: What is SingHaskell? Sing(apore)Haskell is a Haskell (and related languages) meeting in Singapore. The meeting is organized by Tom Schrijvers and Martin Sulzmann and will be hosted by the National University of Singapore. Date and location Sing

Re: [Haskell-cafe] Stream fusion for Hackage

/stream-fusion-0.1.1 As described in the recent paper: Stream Fusion: From Lists to Streams to Nothing at All Duncan Coutts, Roman Leshchinskiy and Don Stewart. ICFP 2007 This is a drop-in replacement for Data.List. Will it eventually replace Data.List in GHC? Tom -- Tom Schrijvers

Re: [Haskell-cafe] Functional dependencies *not* part of the next Haskell standard?

| I think the implementation is some 90% complete though, in GHC head. | Certainly you can write many associated types programs already -- the | missing part is finishing off associated type synonyms, iirc. ...and we have a working implementation of that too, thanks to Tom Schrijvers. It's

Re: [Haskell-cafe] Re: To yi or not to yi, is this really the question? A plea for a cooperative, ubiquitous, distributed integrated development system.

-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- Tom Schrijvers Department of Computer Science K.U. Leuven

[Haskell-cafe] Re: Haskell serialisation, was: To yi or not to yi...

On Thu, 21 Jun 2007, Pasqualino 'Titto' Assini wrote: Hi Tom, On Thursday 21 June 2007 08:59:42 Tom Schrijvers wrote: On Thu, 21 Jun 2007, Pasqualino 'Titto' Assini wrote: Thanks for the explanation. But, doesn't this simply mean that the correct signature would be: serialize :: (Int - Int

Re: [Haskell-cafe] Re: Haskell serialisation, was: To yi or not to yi...

Tom Schrijvers wrote: I understand that, depending on what the compiler does the result of : do let f = (*) 2 print $ serialise f might differ as, for example, the compiler might have rewritten f as \n - n+n. But, why would that make equational reasoning on serialise not valid? Isn't

Re: [Haskell-cafe] Re: Haskell serialisation, was: To yi or not to yi...

On Thursday 21 June 2007, Tom Schrijvers wrote: That wouldn't make a difference. If, from the pure Haskell point of view we can't tell the difference between two expressions that denote the same function, then operations in the IO monad should not be able to do so either. This doesn't make

Re: [Haskell-cafe] Just curios

somewhere than ascribing a Hebrew origin for his name. I found this: HASKEL: Hebrew name meaning intellect. Variant, Haskell, exists. in a list name explanations: http://www.smcm.edu/users/saquade/names.html Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven

Re: [Haskell-cafe] Scope of type variables in associated types

a, OneStep (OS a)) = TwoStep a type TS a = OS (OS a) which are currently under development. -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED

Re: [Haskell-cafe] ambiguous type variables at MPTC

a for which the instance C a b is completely independent of b. There is no ambiguity. Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] ___ Haskell-Cafe

Re: [Haskell-cafe] hash of a lazy bytestring?

... Another solution would be loop fusion: do l - readFile foo len - writeFileAndComputeLength bar l ... A compiler might be able to do that for you. Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16

Re: [Haskell-cafe] Vanishing polymorphism

for it. Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org

Re: [Haskell-cafe] Vanishing polymorphism

the polymorphism get destroyed? Here fn is bound by a lambda abstraction, and is therefore monomorphic. I can't find anything in the Report about that, This won't be in the Haskell 98 report. I have to enable -fglasgow-exts in GHCi to get this even parsed. Tom -- Tom Schrijvers Department

Re: [Haskell-cafe] Re: Compilling GHC on Vista

whether there's already a solution for that in the repository? Tom Cheers, Monique On 4/24/07, Simon Marlow [EMAIL PROTECTED] wrote: Tom Schrijvers wrote: Here's the more complete error message: configure:3321: checking for C compiler default output file name configure:3348: c:/MinGW/bin

Re: [Haskell-cafe] Compilling GHC on Vista

on a simple C program? I had a similar error, cause by the fact that gcc.exe cannot find cc1.exe, which is in MingW/libexec/gcc/mingw32/3.4.2/. I had to add it to my PATH. Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel

Re: [Haskell-cafe] Compilling GHC on Vista

On Mon, 23 Apr 2007, Monique Monteiro wrote: Tom, On 4/23/07, Tom Schrijvers [EMAIL PROTECTED] wrote: What does the config.log say? Are you able to run the MingW's gcc compiler yourself on a simple C program? I had a similar error, cause by the fact that gcc.exe cannot find cc1.exe

Re: [Haskell-cafe] Why does Haskell have the if-then-else syntax?

this cause a conflict with specialized knowledge the compiler has about if-then-else, e.g. for optimizations? Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED

Re: [Haskell-cafe] Re: Type-Level Naturals Like Prolog?

. It's probably good to read a bit about it in a proper reference. Wikipedia's Prolog entry lists a number of tutorials. Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED

Re: [Haskell-cafe] Re: help with MPTC for type proofs?

deriving Show -- This is identical to what Tom Schrijvers wrote class Commutable a b c d | a b c - d, -- 2. a d c - b -- based on 1. + 2. -- But how do we make sure that Commutable a d c b exists whenever -- Commutable a b c d does? very easily: with the help

Re: [Haskell-cafe] help with MPTC for type proofs?

instances of CommutativePartners can be declared. Support for closed type classes is needed to prevent this. I'm not sure whether there is a way to fully realise requirement 1. AFAIK associated types are no more expressive than FDs. Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U

Re: [Haskell-cafe] Code Review: Sudoku solver

comparing a number of all_different algorithms and additional tricks: http://www.computational-logic.org/iccl/master/lectures/winter05/fcp/fcp/sudoku.pdf Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e

Re: [Haskell-cafe] Code Review: Sudoku solver

a strategy language though. Cheers, Tom -- Tom Schrijvers Department of Computer Science K.U. Leuven Celestijnenlaan 200A B-3001 Heverlee Belgium tel: +32 16 327544 e-mail: [EMAIL PROTECTED] ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http