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>Our apologies for the delay. The new FREE download of DPA is ready now at:
by Create FREE Digital Web Books 04 Jan '02

04 Jan '02

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RE: punning in GHC?
by Simon Peyton-Jones 02 Jan '02

02 Jan '02

Punning was removed from Haskell some while ago, I believe when Haskell 98 was fixed in Feb 1999. See the Preface section 0.4.1 Simon | -----Original Message----- | From: Iavor S. Diatchki [mailto:diatchki@cse.ogi.edu] | Sent: 26 December 2001 18:55 | To: haskell(a)haskell.org | Subject: punning in GHC? | | | hi there, | | i just discovered that GHC does not support punning with the | -fglasgow-exts | option. is there another flag to turn this on or has it been | completely | removed? if so could we have it back - i really like the feature (in | patterns anyways) and use it (hugs -98 supports it). i don't | particularly | care that it is not in haskell 98 as i rarely write haskell | 98 programs. | | by the way before posting this i did a search on "punning" | through the | mailing list archive to see if someone asked this already. i | couldnt find | anything but it seems that since 1997 there were 7 posts on | "punning" and | all of them seemed to agree that it was a useful feature, so | why was it | removed? | | bye | iavor | | _______________________________________________ | Haskell mailing list | Haskell(a)haskell.org http://www.haskell.org/mailman/listinfo/haskell |

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Re: instances and modules
by Feuer 01 Jan '02

01 Jan '02

> 2. A missing method definition is assumed to be bottom. > (I don't like this rule. Ghc with suitable options warns in such case. > This definitely sounds like a bad idea... seems to violate intuition about what an instance of a class is... if you can't define a method of the class, you probably don't belong in that class. >The first point is important. It's possible that an overloaded function >in the next version of a library is promoted to a method with a default >definition, and then existing code using that class doesn't break. Understood. Not sure what I think of it. Wouldn't it be better for the new library to include a new class deriving from the old? That would more clearly indicate the relationship... if the class itself changes, the instances should change too.

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Re: instances and modules
by Marcin 'Qrczak' Kowalczyk 01 Jan '02

01 Jan '02

Mon, 31 Dec 2001 22:52:44 -0800, Feuer <feuer(a)his.com> pisze: > I don't understand how a type can be considered an instance of a > class if it doesn't provide all the methods of that class. 1. A method can have a default definition. 2. A missing method definition is assumed to be bottom. (I don't like this rule. Ghc with suitable options warns in such case.) The first point is important. It's possible that an overloaded function in the next version of a library is promoted to a method with a default definition, and then existing code using that class doesn't break. -- __("< Marcin Kowalczyk * qrczak(a)knm.org.pl http://qrczak.ids.net.pl/ \__/ ^^ QRCZAK

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instances and modules
by Feuer 01 Jan '02

01 Jan '02

Some discussion has gone on recently regarding class methods that are and are not passed across module boundaries. One thing that struck me as rather odd was that some/many/all people thought it was reasonable to have module M (C(a)) where class C t where a::... b::... module N (.....) where import M instance C Int where a=..... I don't understand how a type can be considered an instance of a class if it doesn't provide all the methods of that class. Why not make all of these rules much simpler by requiring that a module N can contain an instance declaration for class M.C if, and only if, M exports M.C(..) and N imports M.C(..) (either qualified or unqualified)? I don't see why anyone would want to do something silly like import qualified M as P(a) import qualified M as Q(b) but even if this is useful, I don't think it should be enough to allow an instance declaration for C. The programmer should be required to explicitly say import qualified M as R(..) IMVHO, it should not even be legal to have an instance declaration that imports C(a,b), but that's just me. David Feuer

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ScanMail Message: To Recipient virus found and action taken.
by System Attendant 31 Dec '01

31 Dec '01

ScanMail for Microsoft Exchange has detected virus-infected attachment(s). Sender = Louise Finch Recipient(s) = haskell(a)haskell.org Subject = <no subject> Scanning Time = 12/31/2001 10:39:28 Action on virus found: The attachment HAMSTER.DOC.pif exists WORM_BADTRANS.B virus. ScanMail has Moved it. The attachment was moved to Y:\Program Files\Trend\Smex\Virus\HAMSTER.DOC3c3086b0f.pif_. Warning to recipient. ScanMail detected a virus in an email attachment. The attachment will be cleaned if possible. If the attachment cannot be cleaned , it will be stripped.

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Re:
by Louise Finch 31 Dec '01

31 Dec '01

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Call for Papers: Annals of Software Engineering Special Volume
by asespec＠serg.ing.unisannio.it 30 Dec '01

30 Dec '01

CALL FOR PAPERS -------------------------------------------------------------- Our apologies if you received multiple copy of this. -------------------------------------------------------------- Annals of Software Engineering: Special Volume on "Computational Intelligence In Software Engineering" http://manta.cs.vt.edu/ase The Annals of Software Engineering journal seeks articles for a special volume on "Computational Intelligence In Software Engineering". The constantly evolving technological infrastructure of the modern world presents a great challenge of developing software systems with increasing size and complexity. Software engineers and researchers are striving to meet these and other continuously growing challenges by developing and implementing useful software engineering methodologies. However, despite the introduction of some important and useful paradigms in the software engineering discipline, their technological transfers on a larger scale has been extremely gradual and limited. The recent emergence of the field of Computational Intelligence (CI) in Software Engineering provides a software development team with an opportunity by taking advantage of the currently developed, documented, and mature CI technologies such as fuzzy logic, artificial neural networks, genetic and artificial intelligence based computational systems, expert knowledge based systems, and case based reasoning. These and other computational intelligence technologies have been used to resolve issues arising from the ever-increasing complexity and size of software systems. The aim and scope of this special issue is focused on the current research trends of introducing and implementing CI techniques to address the various software engineering needs arising during different phases of software development and analysis. This special issue is intended to serve as a comprehensive collection of some of the current state-of-the-art CI in software engineering technologies. Topics of Interest Topics of particular interest on "Computational Intelligence In Software Engineering" include but are not limited to: * Neural Networks * Fuzzy Logic * Genetic Algorithms & Programming * Case Based Reasoning * Data Mining Techniques * Adaptive Computing Systems * Knowledge Based Systems * Software Cost Estimation * Software Reliability Modeling * Formal Verification Methods * Software Testing & Software Validation * Expert Software Systems * Software Requirements & Specifications Engineering * Machine Learning Techniques * Hybrid Intelligent Systems Editor Professor Taghi M. Khoshgoftaar Department of Computer Science & Engineering Florida Atlantic University Boca Raton, Florida 33433, U.S.A. Tel: +1-561-297-3994 Fax: +1-561-297-2800 Email: taghi(a)cse.fau.edu Annals of Software Engineering imposes virtually no length limitation on the submitted papers. A paper's length is judged with respect to the quality of its content. Submitted papers must not have been previously published or be currently under consideration for publication elsewhere. All papers will be rigorously refereed. The complete manuscript in PDF or postscript format should be submitted to the editor on or before April 1, 2002. Submission Submission of a manuscript to the Annals of Software Engineering journal is a representation that the manuscript: (a) has not been previously published, (b) is not currently under consideration for publication elsewhere, and (c) will not be submitted elsewhere until a decision is made regarding its suitability for publication in Annals of Software Engineering. Submission is also the representation that the work has been approved for open publication if performed under an official sponsorship requiring such an approval.

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Importing in ghci
by Konst Sushenko 28 Dec '01

28 Dec '01

Hello, I just started using GHCI and I am having trouble importing modules except for these in the "imports/std" directory. I am using windows, and my GHC installation directory is "d:/ghc/ghc-5.02.1". I tried starting ghci with the -i option: ghci -I"d:/ghc/ghc-5.02.1" to no avail... Tried it with quotes, without quotes, tried relative path, no help. 'ghc-pkg -l' reports that the module that I import is indeed in an installed package, and as far as I understand as long as the module is in an installed package, GHC should be happy. What am I missing? Thanks konst

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punning in GHC?
by Iavor S. Diatchki 26 Dec '01

26 Dec '01

hi there, i just discovered that GHC does not support punning with the -fglasgow-exts option. is there another flag to turn this on or has it been completely removed? if so could we have it back - i really like the feature (in patterns anyways) and use it (hugs -98 supports it). i don't particularly care that it is not in haskell 98 as i rarely write haskell 98 programs. by the way before posting this i did a search on "punning" through the mailing list archive to see if someone asked this already. i couldnt find anything but it seems that since 1997 there were 7 posts on "punning" and all of them seemed to agree that it was a useful feature, so why was it removed? bye iavor

1 0