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extenssions of Haskell
by Scott J. 04 Aug '02

04 Aug '02

Hi, I have allrewdy read a lot of Haskell 98. What I cannot find are papers about the State transformermonad in its present form and papers about rank m polymorphism. Thx Scott P.S. Where can I find the windows library for HOpenGL and Haskell+GYK2? bindins. Are rpms for redhat also installable for MandrakeLinux .?

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[Xemacs] x-symbol mode for Haskell
by Jorge Adriano 04 Aug '02

04 Aug '02

Hi, I've always liked the X-Symbol package for Xemacs http://x-symbol.sourceforge.net/ I've searched for Haskell X-Symbol modes, but there doesn't seem to be one. It's kind of strange because it seems to me like most people who are into haskell would like to use non-ascii symbols like greek letters and some nice looking operators - just take a look at some haskell books, LaTeX modes for haskell etc. I tried to hack an x-symbol haskell mode. *I know nothing about elisp* or x-symbol internals so the mode is bloated with useless stuff and *does not works* properly (yet?). It is in fact just a very dirty non working hack... right now I just can't spend much time with it. I thought I'd ask if anyone (preferably with more experience :) is doing, or thinking about doing some good haskell x-symbol mode. J.A. P.S.: Just in case you want to take a look at it here to understand what it is supposedd to do, it goes in attchment. After installing it try typing something like f :: Num _alpha => [_alpha] -> [_alpha] f x = x+x The _alphas will turn into real alphas as you type them, the => and -> will also turn into good looking non-ascii arrows. :) The main problem is that the source file is not beeing saved correctly (decode token works, but not encode token), so you're not going to be able to compile it. Of course there are many other problems like <= turning into an arrow instead of a "less than equal", etc etc etc :) How to install it: X-Symbol: - download the latest x-symbol version. - run xemacs as root - M-x package-admin-add-binary-package (it will tell you the directory where it is installed) The quick-dirty-non-usable-x-symbol-haskell-mode :) - save the "x-symbol-haskell.el" and "x-symbol-hooks.el" files - compile them (open in xemacs, right click buffer, byte-compile this file) - copy (as root) the .el and .elc files to the directory where your other x-symbol .el and .elc files are. You may want to back up your old "x-symbol-hooks.el" file. To "use" it just "M-x x-symbol-mode" in an haskell buffer and type away.

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RE: can a lazy language give fast code?
by Simon Marlow 01 Aug '02

01 Aug '02

> Can one write withthe Haskell compliler faster code than in > the examples of http://www.bagley.org/~doug/shootout/ where > GHC (old Haskell 98?) seems to be much slower than Ocaml or > Mlton both strict functional languages. > Can one expect any improvements in speed in the future? Many of those programs can be written differently to improve performance. One issue that is affecting performance in several cases is the speed of character I/O, and the representation of Strings as lists of characters. Dramatic improvements can be had by using unboxed arrays of Char (Data.Array.Unboxed), or PackedString (which these days is implemented using unboxed arrays in GHC). Cheers, Simon

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can a lazy language give fast code?
by Scott J. 31 Jul '02

31 Jul '02

Hi, Can one write withthe Haskell compliler faster code than in the examples of http://www.bagley.org/~doug/shootout/ where GHC (old Haskell 98?) seems to be much slower than Ocaml or Mlton both strict functional languages. Can one expect any improvements in speed in the future? Cheers Scott

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Re: Infix expressions
by Yoann Padioleau 30 Jul '02

30 Jul '02

Ken Shan <ken(a)digitas.harvard.edu> writes: > --a8Wt8u1KmwUX3Y2C > Content-Type: text/plain; charset=us-ascii > Content-Disposition: inline > Content-Transfer-Encoding: quoted-printable > > Hello, > > In Haskell, backquotes can be used to convert individual identifiers > into infix operators, but not complex expressions. For example, > > [1,2,3] `zip` [4,5,6] > > is OK, but not > > [1,2,3] `zipWith (+)` [4,5,6] > > Is there any reason other than potential confusion when one of the two > backquotes is accidentally omitted? > > In any case, perhaps some people on this mailing list would appreciate > the following implementation of "infix expressions" that Dylan Thurston > and I came up with -- as algebraic and perverse as we could manage: > > infixr 0 -:, :- > data Infix f y =3D f :- y > x -:f:- y =3D x `f` y > > main =3D print $ [1,2,3] -: zipWith (+) :- [4,5,6] This is a funny tricks. Does some people know other kind of tricks (possibly in other functionnal langage) ? > > --=20 > Edit this signature at http://www.digitas.harvard.edu/cgi-bin/ken/sig > The trick is that there is no trick. > > --a8Wt8u1KmwUX3Y2C > Content-Type: application/pgp-signature > Content-Disposition: inline > > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.0.7 (GNU/Linux) > > iD8DBQE9RZgzzjAc4f+uuBURAjl6AKCQmYb0HJvk2VicBlRD6zRX9VfRRgCg9F2B > YPXu07Uqrz8pj2iUt+HVM3U= > =WjJq > -----END PGP SIGNATURE----- > > --a8Wt8u1KmwUX3Y2C-- > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe(a)haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe > -- Yoann Padioleau, INSA de Rennes, France, Opinions expressed here are only mine. Je n'écris qu'à titre personnel. **____ Get Free. Be Smart. Simply use Linux and Free Software. ____**

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Infix expressions
by Ken Shan 29 Jul '02

29 Jul '02

Hello, In Haskell, backquotes can be used to convert individual identifiers into infix operators, but not complex expressions. For example, [1,2,3] `zip` [4,5,6] is OK, but not [1,2,3] `zipWith (+)` [4,5,6] Is there any reason other than potential confusion when one of the two backquotes is accidentally omitted? In any case, perhaps some people on this mailing list would appreciate the following implementation of "infix expressions" that Dylan Thurston and I came up with -- as algebraic and perverse as we could manage: infixr 0 -:, :- data Infix f y = f :- y x -:f:- y = x `f` y main = print $ [1,2,3] -: zipWith (+) :- [4,5,6] -- Edit this signature at http://www.digitas.harvard.edu/cgi-bin/ken/sig The trick is that there is no trick.

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Haskell is more known than we might think
by oleg＠pobox.com 29 Jul '02

29 Jul '02

Hello! The other day I received, among other junk mail, coupons for the local 7-eleven store. I subconsciously scanned the envelope, and almost jumped when I read the return address: 7-Eleven, Inc. 2711 North Haskell Avenue Dallas, TX 75204 It seems a rather long Avenue (with at least 27 blocks); presumably it has the Southern part too. Being associated with the most successful worldwide convenience store chain bodes well for the language.

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(no subject)
by Scott J. 28 Jul '02

28 Jul '02

I think I am in the wrong pub. It seems I am alone here. Scott

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Uluslararas� �� FIRSATI..
by �� F�rsat� 28 Jul '02

28 Jul '02

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converting capital letters into small letters
by Karen Y 27 Jul '02

27 Jul '02

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