Re: [Haskell-cafe] GHCi fails to load C++ object files (missing symbol)

2012-03-08 Thread Hans Aberg
On 8 Mar 2012, at 13:21, Mark Wright wrote: It might work without -fpic on x86 (32 bit): http://www.mail-archive.com/gentoo-dev@gentoo.org/msg01420.html On OS X, it is always on; I tried the example on 10.7, Xcode 4.3. I had to add ln -s /Applications/Xcode.app/Contents/Developer

Re: [Haskell-cafe] C++ Parser?

2012-01-24 Thread Hans Aberg
On 24 Jan 2012, at 11:06, Christopher Brown wrote: I have stumbled across language-c on hackage and I was wondering if anyone is aware if there exists a full C++ parser written in Haskell? There is a yaccable grammar

Re: [Haskell-cafe] black Wikipedia (Was: PhD program at Portland State accepting applications)

2012-01-18 Thread Hans Aberg
On 18 Jan 2012, at 18:49, Andrew Butterfield wrote: Just add ?banner=none to the url if you really have to read the page Or stop the loading before the banner comes up. Hans On 18 Jan 2012, at 17:37, Henning Thielemann wrote: On Wed, 18 Jan 2012, Nathan Collins wrote: - Portland is

Re: [Haskell-cafe] black Wikipedia

2012-01-18 Thread Hans Aberg
On 18 Jan 2012, at 19:32, John Meacham wrote: Not to mention ebay, craigslist, etc.. http://www.techdirt.com/articles/20111005/10082416208/monster-cable-claims-ebay-craigslist-costco-sears-are-rogue-sites.shtml when there is no burden of proof for someone to take down a site then things

Re: [Haskell-cafe] black Wikipedia

2012-01-18 Thread Hans Aberg
On 18 Jan 2012, at 23:11, Brandon Allbery wrote: There is the Beastie Boys case, where the judge decided copyright protects what is creatively unique. But such judgments are rare, sadly. And for every Beastie Boys case there's at least one The Verve case. I did not know that. But it was

Re: [Haskell-cafe] black Wikipedia

2012-01-18 Thread Hans Aberg
the code uploaded, but the targets of any urls within said code/description... and retroactively remove stuff if said links change to contain objectional material. (for a very vauge definition of objectionable). it is a really messed up law. John On Wed, Jan 18, 2012 at 2:46 PM, Hans Aberg

Re: [Haskell-cafe] GHC exceeding command line length limit with split-objs - and a possible fix

2012-01-11 Thread Hans Aberg
On 11 Jan 2012, at 13:38, John Lato wrote: I used https://github.com/kennethreitz/osx-gcc-installer/downloads to get a real gcc on Lion. Biggish download, but it worked. I've also seen reports of success by self-compiling gcc, or by installing XCode 4 on top of an existing XCode 3

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-26 Thread Hans Aberg
On 26 Dec 2011, at 16:11, AUGER Cédric wrote: There is http://www.stixfonts.org/ For typesetting with Xe[La]TeX or Lua[La]TeX, use XITS (in the TeXLive package). (And then we'll have to deal with folks trying to use the letter, because everyone knows the Roman alphabet is the only one

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-26 Thread Hans Aberg
On 26 Dec 2011, at 19:29, AUGER Cédric wrote: Le Mon, 26 Dec 2011 18:20:55 +0100, Hans Aberg haber...@telia.com a écrit : On 26 Dec 2011, at 16:11, AUGER Cédric wrote: Under Xorg, XCompose might be your friend! I have a whole bunch of them for Coq programing. Having something like

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-26 Thread Hans Aberg
On 26 Dec 2011, at 23:03, Brandon Allbery wrote: But if you are under Windows, or Mac OS, I cannot tell (as well as I cannot tell if you are under a POSIX system not running xorg, such as the tty1..ttyn consoles) On OS X one can make ones owns key maps, like with the program on the link

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-26 Thread Hans Aberg
On 27 Dec 2011, at 01:02, Donn Cave wrote: Quoth Hans Aberg, ... For example, I set one entry so that typing x |- a becomes x ↦ a, the TeX \mapsto, in Unicode ↦ RIGHTWARDS ARROW FROM BAR U+21A6. It might be tedious to make a lot of entries, though, but something to start

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-21 Thread Hans Aberg
On 21 Dec 2011, at 04:15, Brandon Allbery wrote: On Tue, Dec 20, 2011 at 21:05, Andrew Cowie and...@operationaldynamics.com wrote: Now we just need λ to replace \, → to replace -, and ≠ to replace /= (which still looks like division assignment no matter how hard I squint my eyes. 25 years

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-21 Thread Hans Aberg
On 21 Dec 2011, at 04:27, Ashok Gautham wrote: On Tue, Dec 20, 2011 at 11:17:32PM +0100, Hans Aberg wrote: The monospace characters U+1D670-1D6A3 might be used for keywords. Font: http://www.stixfonts.org/ I feel that monospace fonts should be used for all of programming. A language could

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-21 Thread Hans Aberg
On 21 Dec 2011, at 11:03, Brandon Allbery wrote: On Wed, Dec 21, 2011 at 04:51, Hans Aberg haber...@telia.com wrote: The one on the list is not a mathematical symbol. It should be ⋆ STAR OPERATOR U+22C6 or ∗ ASTERISK OPERATOR U+2217. ...except, at least in my current font, the former

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-21 Thread Hans Aberg
readable, taking away the fact that it may take some time to get used to it, since monospace has been used so much. For such alignments, one would either to write to code so it does not depend on it, or find some other means to do it. Hans On Wed, Dec 21, 2011 at 8:58 PM, Hans Aberg haber

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-21 Thread Hans Aberg
On 21 Dec 2011, at 11:22, Andrew Coppin wrote: On 21/12/2011 10:09 AM, Jesse Schalken wrote: IIRC, Scite's default configuration is with non-monospace font. I actually found it quite appealing, and in fact forgot about it entirely after some usage. It is much easier on the eyes to read. The

Re: [Haskell-cafe] If you'd design a Haskell-like language, what would you do different?

2011-12-20 Thread Hans Aberg
On 20 Dec 2011, at 22:51, Chris Wong wrote: One thing that concerns me is the use of capital letters to distinguish type and class names and constructors from values. If I was doing it over I would use a typographical distinction like italics for types, bold for classes. That way we could

Re: [Haskell-cafe] A Mascot

2011-11-16 Thread Hans Aberg
On 16 Nov 2011, at 05:18, John Meacham wrote: People tend to concentrate on the lambda which cooresponds to the functional aspect of haskell when designing logos. Not nearly enough attention is paid to the other striking feature, the laziness. The 'bottom' symbol _|_ should feature

Re: [Haskell-cafe] A Mascot

2011-11-16 Thread Hans Aberg
On 16 Nov 2011, at 23:49, heathmatlock wrote: I took Jerzy's suggestions into consideration and made the lamb skinnier, maybe it looks less like a penguin now. http://imgur.com/4oeJz A formula that is Haskell specific is \x - ⊥ ≠ ⊥ It is mentioned in the Haskell 98 Report, sec. 6.2,

Re: [Haskell-cafe] Lambda Calculus: Bound and Free formal definitions

2010-12-30 Thread Hans Aberg
On 30 Dec 2010, at 03:05, Mark Spezzano wrote: ... regarding formal definitions of FREE and BOUND variables he gives Defn 5.2 as It is the occurrence of a variable that is free or bound. An occurrence of a variable is bound if it is in the scope of something that binds it; otherwise it

[Haskell-cafe] Hugs Haskore loading

2010-08-21 Thread Hans Aberg
When trying to load Haskore in Hugs Sept 2006 (say by :l), it does not work because it is in a subdirectory Haskore/Src/, despite that the Hugs searchpath includes /usr/local/lib/hugs/packages/* I could of course change this searchpath, but I'm curios about how to fix it without it - it

Re: [Haskell-cafe] Hugs Haskore loading

2010-08-21 Thread Hans Aberg
On 21 Aug 2010, at 20:24, Henning Thielemann wrote: When trying to load Haskore in Hugs Sept 2006 (say by :l), it does not work because it is in a subdirectory Haskore/Src/, despite that the Hugs searchpath includes /usr/local/lib/hugs/packages/* I could of course change this searchpath,

Re: [Haskell-cafe] Hugs Haskore loading

2010-08-21 Thread Hans Aberg
On 21 Aug 2010, at 20:24, Henning Thielemann wrote: When trying to load Haskore in Hugs Sept 2006 (say by :l), it does not work because it is in a subdirectory Haskore/Src/, despite that the Hugs searchpath includes /usr/local/lib/hugs/packages/* I could of course change this searchpath,

Re: [Haskell-cafe] Hugs Haskore loading

2010-08-21 Thread Hans Aberg
On 21 Aug 2010, at 20:57, Henning Thielemann wrote: Did you install Haskore with Cabal or is it a version of Haskore that is shipped with Hugs? It is the version that comes with Hugs. It is the same as listed on http://haskell.org/haskore/ . What other version do you have in mind. There

Re: [Haskell-cafe] Hugs Haskore loading

2010-08-21 Thread Hans Aberg
On 21 Aug 2010, at 20:57, Henning Thielemann wrote: Did you install Haskore with Cabal or is it a version of Haskore that is shipped with Hugs? It is the version that comes with Hugs. It is the same as listed on http://haskell.org/haskore/ . What other version do you have in mind. There

Re: [Haskell-cafe] Hugs Haskore loading

2010-08-21 Thread Hans Aberg
On 21 Aug 2010, at 21:51, Henning Thielemann wrote: and one that I have messed http://hackage.haskell.org/package/haskore What changes have you made? - perhaps the packages should be unified. I changed almost everything: Divided modules, designed a hierarchy for module names, generalized

Re: [Haskell-cafe] ghc in macports

2010-08-12 Thread Hans Aberg
On 12 Aug 2010, at 12:49, Benedict Eastaugh wrote: On 11 August 2010 15:49, Ozgur Akgun ozgurak...@gmail.com wrote: Personally, I'd like to use the macports version, if the ghc version there was resonably recent (having 2 versions, a stable and an edge could be a good idea?) You could

Re: [Haskell-cafe] ghc in macports

2010-08-12 Thread Hans Aberg
On 12 Aug 2010, at 14:08, Ozgur Akgun wrote: On http://wiki.github.com/mxcl/homebrew/installation it says: delete /usr/local/include and/usr/local/lib So its not for those that also installs standard distributions, it seems. I thought this was just a recommendation. It also says:

Re: [Haskell-cafe] ghc in macports

2010-08-12 Thread Hans Aberg
On 12 Aug 2010, at 20:46, Gaius Hammond wrote: its not for those that also installs standard distributions, it seems. But what's wrong with the binaries listed here: http://haskell.org/ghc/ Fairly easy to install. Yes and no; on OSX 10.5.8 it works better to install GHC from the binary

Re: [Haskell-cafe] lambdacats

2010-08-06 Thread Hans Aberg
On 6 Aug 2010, at 09:48, Andrew Coppin wrote: Hello, does anyone happen to have the lambdacats page cached? The domain (arcanux.org http://arcanux.org) and server have disappeared and the wayback machine doesn't have the images. Somebody else noticed, eh? Good thing I grabbed most of the

Re: [Haskell-cafe] Suggestions For An Intro To Monads Talk.

2010-08-04 Thread Hans Aberg
On 3 Aug 2010, at 23:51, aditya siram wrote: I am doing an Intro To Monads talk in September [1]. The audience consists of experienced non-Haskell developers but they will be familiar with basic functional concepts (closures, first-class functions etc.). I am looking for suggestions on

Re: [Haskell-cafe] Category Theory woes

2010-02-19 Thread Hans Aberg
On 19 Feb 2010, at 00:52, Richard O'Keefe wrote: Turning to the Wikipedia article, we find The word kangaroo derives from the Guugu Yimidhirr word gangurru, referring to a grey kangaroo Thanks, particularly for giving the name of the native language. Hope the Wikipedia article can be

Re: [Haskell-cafe] Category Theory woes

2010-02-19 Thread Hans Aberg
On 19 Feb 2010, at 00:05, Nick Rudnick wrote: Mathematicians though stick to their own concepts and definitions individually. For example, I had conversations with one who calls monads triads, and then one has to cope with that. Yes. But isn't it also an enrichment by some way? Yes, one

Re: [Haskell-cafe] Category Theory woes

2010-02-19 Thread Hans Aberg
On 19 Feb 2010, at 00:55, Daniel Fischer wrote: I'd always assumed ring was generalised from Z[n]. As in cyclic group, arrange the numbers in a ring like on a clockface? Maybe. As far as I know, the term ring (in the mathematical sense) first appears in chapter 9 - Die Zahlringe des

Re: [Haskell-cafe] Category Theory woes

2010-02-19 Thread Hans Aberg
On 19 Feb 2010, at 12:12, Daniel Fischer wrote: ...As far as I know, the term ring (in the mathematical sense) first appears in chapter 9 - Die Zahlringe des Körpers - of Hilbert's Die Theorie der algebraischen Zahlkörper. Unfortunately, Hilbert gives no hint why he chose that name (Dedekind,

Re: [Haskell-cafe] Category Theory woes

2010-02-18 Thread Hans Aberg
On 18 Feb 2010, at 14:48, Nick Rudnick wrote: * the definition of open/closed sets in topology with the boundary elements of a closed set to considerable extent regardable as facing to an «outside» (so that reversing these terms could even appear more intuitive, or «bordered» instead of

Re: [Haskell-cafe] Category Theory woes

2010-02-18 Thread Hans Aberg
On 18 Feb 2010, at 20:20, Daniel Fischer wrote: + definition backtracking: «A closure operation c is defined by the property c(c(x)) = c(x). Actually, that's incomplete, ... That's right, it is just the idempotency relation. ...missing are - c(x) contains x - c(x) is minimal among the

Re: [Haskell-cafe] Category Theory woes

2010-02-18 Thread Hans Aberg
On 18 Feb 2010, at 19:19, Nick Rudnick wrote: agreed, but, in my eyes, you directly point to the problem: * doesn't this just delegate the problem to the topic of limit operations, i.e., in how far is the term «closed» here more perspicuous? * that's (for a very simple concept) the way

Re: [Haskell-cafe] Category Theory woes

2010-02-18 Thread Hans Aberg
On 18 Feb 2010, at 22:06, Daniel Fischer wrote: ...missing are - c(x) contains x - c(x) is minimal among the sets containing x with y = c(y). It suffices*) with a lattice L with relation = (inclusion in the case of sets) satifying i. x = y implies c(x) = c(y) ii. x = c(x) for all x in

Re: [Haskell-cafe] Category Theory woes

2010-02-18 Thread Hans Aberg
On 18 Feb 2010, at 23:02, Nick Rudnick wrote: 418 bytes in my file system... how many in my brain...? Is it efficient, inevitable? Yes, it is efficient conceptually. The idea of closed sets let to topology, and in combination with abstractions of differential geometry led to cohomology

Re: [Haskell-cafe] multMM :: Matrix - Matrix - Matrix --multiplies two matrices question (Homework)

2010-02-03 Thread Hans Aberg
On 3 Feb 2010, at 07:38, 조광래 wrote: hi i was trying to solve it but All i got is type Matrix=[[Double]] multMM :: Matrix - Matrix - Matrix --multiplies two matrices multMM m t =[[sum (zipWith (*) (head m)(a)) ] ]where a = [head a | a- t] Main multMM [[2,1,-6],[1,-3,2]]

Re: [Haskell-cafe] Very imperfect hash function

2010-02-02 Thread Hans Aberg
On 2 Feb 2010, at 03:05, Richard O'Keefe wrote: A simple hash-function for strings is to simply exclusive-or the bytes and then reduce modulo a prime number, Simply exclusive-oring the bytes will give you at most 256 distinct results. (For an ASCII source, 128 distinct results.) After

Re: [Haskell-cafe] matrix question

2010-02-02 Thread Hans Aberg
On 2 Feb 2010, at 13:15, 조광래 wrote: define functions type Matrix=[[Double]] multMM :: Matrix - Matrix - Matrix --multiplies two matrices det :: Matrix - Double --computes the determinant of a matrix inv :: Matrix - Matrix --inverts a matrix i stuck on those problems can any one help me out?

Re: [Haskell-cafe] OT: Literature on translation of lambda calculus to combinators

2010-02-01 Thread Hans Aberg
On 28 Jan 2010, at 10:54, Dušan Kolář wrote: Could anyone provide a link to some paper/book (electronic version of both preferred, even if not free) that describes an algorithm of translation of untyped lambda calculus expression to a set of combinators? Preferably SKI or BCKW. I'm either

Re: [Haskell-cafe] Very imperfect hash function

2010-01-31 Thread Hans Aberg
On 31 Jan 2010, at 20:07, John Lato wrote: Or are you suggesting an actual hash table? The hash function folds the keys onto an interval. Since you have Int values k, you might just use a mod k n function for that. If it's the latter, I'm not certain where the array fits into the

Re: [Haskell-cafe] Strange random choice algorithm

2010-01-30 Thread Hans Aberg
On 30 Jan 2010, at 20:59, michael rice wrote: I'm not sure where I got this PICK function from, and don't understand why it's written as it is, so I wanted to test it for randomness. It seems random enough. But if I understand the algorithm correctly, instead of selecting one of the

Re: [Haskell-cafe] Very imperfect hash function

2010-01-29 Thread Hans Aberg
On 29 Jan 2010, at 12:52, John Lato wrote: There are minimal perfect hash functions; there are some libraries mentioned here, though they are not in Haskell code: http://en.wikipedia.org/wiki/Perfect_hash_function This is suitable when you do a lot of lookups with few key updates. An

Re: [Haskell-cafe] Very imperfect hash function

2010-01-29 Thread Hans Aberg
On 29 Jan 2010, at 15:57, John Lato wrote: That looks interesting too. Yet another idea: use arrays http://haskell.org/haskellwiki/Arrays Then build a hash table, say just taking mod k n, and have values in some lookup map. If n set of keys, average time complexity is O(1), and arrays

Re: [Haskell-cafe] Map unionWith generalization

2010-01-28 Thread Hans Aberg
On 28 Jan 2010, at 03:09, Twan van Laarhoven wrote: For example, in Map String Integer (sparse representation of monomials) compute the minimum value of all associative pairs with the same key (the gcd); if only one key is present, the absent should be treated as having value 0. So

Re: [Haskell-cafe] Very imperfect hash function

2010-01-28 Thread Hans Aberg
On 28 Jan 2010, at 20:07, Steve Schafer wrote: The data are currently in a large lookup table. To save space, I'd like to convert that into a sort of hash function: hash :: key - value My question is this: Is there any kind of generic approach that can make use of the knowledge about the

[Haskell-cafe] Map unionWith generalization

2010-01-27 Thread Hans Aberg
I need ideally some generalizations of unionWith and unionWithKey, for efficiency matters (i.e. avoiding conversions and traversing the maps more than once). I could use a modification of the code in Map.hs, but then the problem is that the module Map interface does not export the

Re: [Haskell-cafe] Map unionWith generalization

2010-01-27 Thread Hans Aberg
On 27 Jan 2010, at 14:56, Jan-Willem Maessen wrote: So here, one would want: (a - c) - (b - c) - (a - b - c) - Map k a - Map k b - Map k c where the two first functions are applied when the first or second key is missing. Ah, the swiss army knife function on maps. This particular

Re: [Haskell-cafe] Map unionWith generalization

2010-01-27 Thread Hans Aberg
On 27 Jan 2010, at 16:33, Jan-Willem Maessen wrote: I'm not sure why you want to throw in functions between maps in the two first arguments. Then there is no requirement that single keys are preserved. But it is a good idea to have a Maybe so that one can remove keys on the fly. A good

Re: [Haskell-cafe] Map unionWith generalization

2010-01-27 Thread Hans Aberg
On 27 Jan 2010, at 21:29, Jan-Willem Maessen wrote: I'm thinking about (k - Maybe a - Maybe b - Maybe c) - Map k a - Map k b - Map k c The first two Maybe's tell if the keys are present, the last if one wants it in the resulting map. That has the same behavior semantically, but it's no more

Re: [Haskell-cafe] Parse error

2010-01-17 Thread Hans Aberg
On 17 Jan 2010, at 11:44, Andrew Coppin wrote: Urg, but that's *ugly*. Is there no way I can reduce the amount of indentation to something more reasonable? main = do putStrLn Line 1 putStrLn Line 2 let xs = do x - [1..10] y - [1..10] return (x+y) print xs That

Re: [Haskell-cafe] help with musical data structures

2009-11-15 Thread Hans Aberg
On 15 Nov 2009, at 12:55, Stephen Tetley wrote: http://hackage.haskell.org/packages/archive/haskore/0.1/doc/html/Haskore-Basic-Pitch.html but maybe it is not what you need, since it distinguishes between C sharp and D flat and so on. The enharmonic doublings and existing Ord instance

Re: [Haskell-cafe] Pattern matching does not work like this?

2009-07-15 Thread Hans Aberg
On 15 Jul 2009, at 12:25, Eugene Kirpichov wrote: If ++ could be pattern matched, what should have been the result of let (x++y)=[1,2,3] in (x,y)? It will branch. In terms of unification, you get a list of substitutions. Hans ___

Re: [Haskell-cafe] Pattern matching does not work like this?

2009-07-15 Thread Hans Aberg
On 15 Jul 2009, at 13:22, Luke Palmer wrote: If ++ could be pattern matched, what should have been the result of let (x++y)=[1,2,3] in (x,y)? It will branch. In terms of unification, you get a list of substitutions. f :: [a] - ([a],[a]) f (x ++ y) = (x,y) For an argument s, any pair (x,

Re: [Haskell-cafe] gcd

2009-05-03 Thread Hans Aberg
On 2 May 2009, at 04:05, Steve wrote: Why is gcd 0 0 undefined? In math, one may define gcd(x, y) as a generator of the ideal generated by x and y in the ring of integers Z. The gcd(x, y) then always exists as the ring Z is a PID (principal ideal domain), i.e., all ideals can be

Re: [Haskell-cafe] Re: Ease of Haskell development on OS X?

2009-03-22 Thread Hans Aberg
, if there are system ones available, then may be used - a GCC quirk. So in such cases, one might have to edit the libpath so that the system libraries are not at all there, moving selected one out of the way, using libtools or something. This is very technical, though. Hans Aberg

Re: [Haskell-cafe] Re: Ease of Haskell development on OS X?

2009-03-22 Thread Hans Aberg
is Version 3.1.2, though I do not know if it is the absolutely latest). Hans Aberg ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

Re: [Haskell-cafe] Re: Ease of Haskell development on OS X?

2009-03-22 Thread Hans Aberg
On 22 Mar 2009, at 12:45, Colin Adams wrote: No. It's all recent. And MacPorts installs its own gcc. Achim Scheider pointed out that the compiler name is missing, so the shell tries to execute '-DNDEBUG' as a program. When I try it, I get: $ sudo port install python_select Password: ---

Re: [Haskell-cafe] Re: Ease of Haskell development on OS X?

2009-03-22 Thread Hans Aberg
On 22 Mar 2009, at 11:32, Colin Adams wrote: I tried issuing the sudo port install command on the wiki page. What did you try to install? ... After some time running it failed with: To fully complete your installation and make python 2.5 the default, please run sudo port install

Re: [Haskell-cafe] Re: Ease of Haskell development on OS X?

2009-03-22 Thread Hans Aberg
On 22 Mar 2009, at 13:42, Colin Adams wrote: After some time running it failed with: To fully complete your installation and make python 2.5 the default, please run sudo port install python_select sudo python_select python25 ...The thing is that when I removed python_select and

Re: [Haskell-cafe] Ease of Haskell development on OS X?

2009-03-21 Thread Hans Aberg
On 21 Mar 2009, at 01:10, Brandon S. Allbery KF8NH wrote: On 2009 Mar 20, at 17:02, Hans Aberg wrote: Therefore, as mentioned before, it might be best to install the GHC binaries and install libraries like Gtk+ from MacPorts. There is also Intel Gtk+ that binds directly to Aqua

Re: [Haskell-cafe] Ease of Haskell development on OS X?

2009-03-20 Thread Hans Aberg
which does safety checks.) Hans Aberg # Add to end of searchpath: append_path() { if ! eval test -z \\${$1##*:$2:*}\ -o -z \\${$1%%*:$2}\ -o - z \\${$1##$2:*}\ -o -z \\${$1##$2}\ ; then eval $1=\$$1:$2 fi } # Add to beginning of searchpath: prepend_path() { if ! eval test -z

Re: [Haskell-cafe] Ease of Haskell development on OS X?

2009-03-20 Thread Hans Aberg
On 20 Mar 2009, at 22:44, Miguel Mitrofanov wrote: Here is info about ghc: $ port info ghc ghc 6.8.3, Revision 1, lang/ghc (Variants: universal, darwin_6, darwin_7, darwin_8_powerpc, darwin_8_i386, darwin_9_powerpc, darwin_9_i386, no_opengl) http://haskell.org/ A bit out of date:

Re: [Haskell-cafe] Ease of Haskell development on OS X?

2009-03-20 Thread Hans Aberg
On 20 Mar 2009, at 22:44, Miguel Mitrofanov wrote: A bit out of date: MigMit:~ MigMit$ port info ghc ghc @6.10.1, Revision 8 (lang, haskell) ...blah-blah... Maybe, your $(port version) is still 1.600? Yes, now it worked: $ port version Version: 1.700 $ port info ghc ghc @6.10.1, Revision 9

Re: [Haskell-cafe] Re: Theory about uncurried functions

2009-03-05 Thread Hans Aberg
(and since the interval [0, 1] and R can be shown having the same cardinalities), GHC implies card R = card 2^ω. (Here, ω is a lower case omega, denoting the first infinite ordinal.) Hans Aberg ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http

Re: [Haskell-cafe] Re: Theory about uncurried functions

2009-03-05 Thread Hans Aberg
hypothesis is 2^Aleph_0 == Aleph_1, which is quite something different from 2^Aleph_0 == card(R). Yes, right, card R = 2^Aleph_0, as you said, and Aleph_1 is defined as the smallest cardinal greater than Aleph_0. Hans Aberg ___ Haskell-Cafe

Re: [Haskell-cafe] Re: Theory about uncurried functions

2009-03-05 Thread Hans Aberg
classes are then at most countable. So one can set up a bijection on each equivalence class: easy for at most countable sets. Then paste it together. The axiom of choice probably implicit here. Hans Aberg ___ Haskell-Cafe mailing list Haskell-Cafe

Re: [Haskell-cafe] Re: Theory about uncurried functions

2009-03-05 Thread Hans Aberg
. Mendelson says AC is in fact equivalent proving all x, y: card x = card y or card y = card x Hans Aberg ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

Re: [Haskell-cafe] Theory about uncurried functions

2009-03-03 Thread Hans Aberg
addition needed is to add the objects (x_1, ..., x_n), n = 0, 1, 2, ..., to your language. You can still curry the functions if you like to - a convention, just as already noted. Hans Aberg ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org

Re: [Haskell-cafe] Origins of '$'

2008-12-09 Thread Hans Aberg
On 8 Dec 2008, at 23:15, Joachim Breitner wrote: Am Montag, den 08.12.2008, 15:59 -0600 schrieb Nathan Bloomfield: Slightly off topic, but the A^B notation for hom-sets also makes the natural isomorphism we call currying expressable as A^(BxC) = (A^B) ^C. So A^(B+C) = A^B × A^C ? Oh,

Re: [Haskell-cafe] Origins of '$'

2008-12-07 Thread Hans Aberg
On 7 Dec 2008, at 11:34, Luke Palmer wrote: On Sun, Dec 7, 2008 at 3:05 AM, Hans Aberg [EMAIL PROTECTED] wrote: One can define operators a ^ b := b(a) -- Application in inverse. (a * b)(x) := b(a(x)) -- Function composition in inverse. (a + b)(x) := a(x) * b(x) O(x) := I

Re: [Haskell-cafe] Origins of '$'

2008-12-07 Thread Hans Aberg
On 7 Dec 2008, at 04:30, George Pollard wrote: This is a little bit random, but I was just wondering if anyone knew where the $ low-precedence parenthesis-eliminating application operator originated. The Haskell Report doesn't mention anything, and I can't search for $ on Google. So... who

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

2008-04-25 Thread Hans Aberg
On 18 Apr 2008, at 20:04, Martin Sulzmann wrote: Let's consider our running example class D a b | a - b instance D a b = D [a] [b] which we can write in CHR notation D a b, D a c == b=c(FD) D [a] [b] = D a b (Inst) These rules overlap. I experimented with translations into GNU

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

2008-04-25 Thread Hans Aberg
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 of :- as logical connective = rather

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

2008-04-25 Thread Hans Aberg
On 25 Apr 2008, at 15:38, 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 of :- as logical connective = rather

[Haskell-cafe] Funny State monad dependency

2008-04-16 Thread Hans Aberg
as the length of the second argument. Hans Aberg import Control.Monad.State f :: Monad a = a b - a c - a c f x y = x = (return y) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell

Re: [Haskell-cafe] Funny State monad dependency

2008-04-16 Thread Hans Aberg
On 16 Apr 2008, at 15:22, Daniel Fischer wrote: The point is the instance Monad ((-) a) where return x = const x f = g = \x - g (f x) x which is defined in Control.Monad.Instances... Thank you. I suspected there was an instance somewhere, and I wanted to know where it is defined.

Re: [Haskell-cafe] Funny State monad dependency

2008-04-16 Thread Hans Aberg
On 16 Apr 2008, at 15:14, Miguel Mitrofanov wrote: Before somebody noticed: I'm wrong. It's not List monad, but also a (-) x monad, also defined in Control.Monad. Therefore, return y is just const y. Therefore, x = (return y) = x = (const y) = x y Right. It is an interesting monad, but

Re: [Haskell-cafe] instance Monad m = Functor m

2008-04-10 Thread Hans Aberg
On 9 Apr 2008, at 17:49, Henning Thielemann wrote: Additionally I see the problem, that we put more interpretation into standard symbols by convention. Programming is not only about the most general formulation of an algorithm but also about error detection. E.g. you cannot compare complex

Re: [Haskell-cafe] instance Monad m = Functor m

2008-04-09 Thread Hans Aberg
On 9 Apr 2008, at 11:26, Jules Bean wrote: Using 'hugs -98', I noticed it accepts: instance Monad m = Functor m where fmap f x = x = return.f Has this been considered (say) as a part of the upcoming Haskell Prime? This forbids any Functors which are not monads. Unless you allow

Re: [Haskell-cafe] instance Monad m = Functor m

2008-04-09 Thread Hans Aberg
On 9 Apr 2008, at 15:23, Henning Thielemann wrote: I don't know if it is possible to extend the syntax this way, but it would be closer to math usage. And one would avoid duplicate definitions just to indicate different operator names, like: class AdditiveMonoid a where o :: a (+) :: a -

Re: [Haskell-cafe] instance Monad m = Functor m

2008-04-09 Thread Hans Aberg
On 9 Apr 2008, at 15:23, Henning Thielemann wrote: I also recognized that problem in the past, but didn't know how to solve it. In Haskell 98, methods are resolved using the types of the operands. How would the compiler find out which implementation of (+) to choose for an expression like

Re: [Haskell-cafe] instance Monad m = Functor m

2008-04-09 Thread Hans Aberg
On 9 Apr 2008, at 16:26, Henning Thielemann wrote: I think a classical example are number sequences which can be considered as rings in two ways: 1. elementwise multiplication 2. convolution and you have some function which invokes the ring multiplication f :: Ring a = a - a and a

Re: [Haskell-cafe] instance Monad m = Functor m

2008-04-09 Thread Hans Aberg
On 9 Apr 2008, at 16:26, Henning Thielemann wrote: 1. elementwise multiplication 2. convolution and you have some function which invokes the ring multiplication f :: Ring a = a - a and a concrete sequence x :: Sequence Integer what multiplication (elementwise or convolution) shall be used

Re: [Haskell-cafe] instance Monad m = Functor m

2008-04-09 Thread Hans Aberg
On 9 Apr 2008, at 17:49, Henning Thielemann wrote: Additionally I see the problem, that we put more interpretation into standard symbols by convention. Programming is not only about the most general formulation of an algorithm but also about error detection. E.g. you cannot compare complex

Re: [Haskell-cafe] instance Monad m = Functor m

2008-04-09 Thread Hans Aberg
On 9 Apr 2008, at 17:49, Henning Thielemann wrote: Also (2*5 == 7) would surprise people, if (*) is the symbol for a general group operation, and we want to use it for the additive group of integers. One might resolve the Num binding of (+) problem by putting all operators into an

Re: Re[2]: [Haskell-cafe] deriving

2008-04-08 Thread Hans Aberg
On 8 Apr 2008, at 00:30, Bulat Ziganshin wrote: At least Hugs complains if one does not indent deriving ..., but I do not know what the standard says. If is required, then it can be changed. deriving is a part of data clause and indentation just allows us to continue clause from prev. line. if

[Haskell-cafe] instance Monad m = Functor m

2008-04-08 Thread Hans Aberg
Using 'hugs -98', I noticed it accepts: instance Monad m = Functor m where fmap f x = x = return.f Has this been considered (say) as a part of the upcoming Haskell Prime? Hans Aberg ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http

Re: Re[4]: [Haskell-cafe] deriving

2008-04-08 Thread Hans Aberg
On 8 Apr 2008, at 10:47, Bulat Ziganshin wrote: deriving which I think is not used elsewhere. It will break a lot of code, but it is easy to change, and also easy to make a compatibility mode. it's also easy to replace all the books, update all code repositories and reteach all the programmers

Re: Re[4]: [Haskell-cafe] deriving

2008-04-08 Thread Hans Aberg
On 8 Apr 2008, at 15:26, PR Stanley wrote: I'm sure you could introduce change gradually without too much pain. So then you only have to get the compilers to gradually understand it :-). I personally think deriving is a descriptive term, now that I understand its role better. There are

Re: [Haskell-cafe] deriving

2008-04-08 Thread Hans Aberg
On 8 Apr 2008, at 16:32, Anton van Straaten wrote: There are two processes here: deriving, i.e., inheriting an interface; and instantiating, i.e., producing running code. Haskell denotes derivation by =. And data a deriving (b_1, ..., b_k) is really a short for data a instance b_1

Re: [Haskell-cafe] deriving

2008-04-08 Thread Hans Aberg
On 8 Apr 2008, at 16:57, Anton van Straaten wrote: So what is the difference from the current state? None. See how efficient a solution it is? ;) So for a change, you propose it should be the same. So you are one of those A-programmers :-). Seriously, there's only so much connotational

Re: [Haskell-cafe] Re: deriving

2008-04-08 Thread Hans Aberg
On 8 Apr 2008, at 17:03, Christian Maeder wrote: deriving Eq i.e. following data List a = List a creates an instance like: instance Eq a = Eq (List a) where compiler implementation The problem was discussed for Stand-alone deriving declarations:

Re: [Haskell-cafe] Function Precedence

2008-04-08 Thread Hans Aberg
On 2 Apr 2008, at 16:20, Loup Vaillant wrote: class AdditiveSemiMonoid a where (+) :: a - a - a Err, why *semi* monoid? Plain monoid would not be accurate? I found an example where it is crucial that the monoid has a unit: When given a monoid m, then one can also define an m-algebra, by

Re: [Haskell-cafe] deriving

2008-04-07 Thread Hans Aberg
be able to distinguish data Bool = False | True instance (Eq) from data Bool = False | True instance Eq Bool where x == y = ... One wants to be able to do that with as little lookahead as possible. Hans Aberg ___ Haskell-Cafe mailing list

Re: [Haskell-cafe] deriving

2008-04-07 Thread Hans Aberg
On 7 Apr 2008, at 21:48, Brandon S. Allbery KF8NH wrote: But here, one would have to think about how the compiler should be able to distinguish data Bool = False | True instance (Eq) from data Bool = False | True instance Eq Bool where x == y = ... Layout already does that,

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