[Haskell-cafe] ANNOUNCE: smt-lib-0.0.1
smt-lib [1] is a library for reading and writing SMT-LIB [2] files via Haskell. SMT-LIB is a common language and benchmark suite used by most SMT solvers. Currently the library supports the full SMT-LIB version 2 syntax. However at this time, only command scripts -- not responses -- can be parsed. Comments, bug reports, or suggestions for improvements welcome. -Tom [1] http://hackage.haskell.org/package/smt-lib [2] http://goedel.cs.uiowa.edu/smtlib/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] ANNOUNCE: feldspar 0.3
On behalf of the Feldspar team, I'm happy to announce a new release of the embedded language Feldspar and its C code generator: http://hackage.haskell.org/package/feldspar-language http://hackage.haskell.org/package/feldspar-compiler The main changes in 0.3 are: * Signed/unsigned integers of different bit widths (8, 16 and 32). * Fixed-point numbers. * Slight change of the vector library interface: All intermediate vectors are guaranteed to be removed. * A new Stream data type. * Support for user-defined types. * Tracing functions. * Limited support for code generations for the TMS320C64x chip family. * Bugfixes. For more information, see: http://feldspar.inf.elte.hu/feldspar/ / Emil ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
On Fri, Jul 16, 2010 at 10:00 PM, Christopher Done chrisd...@googlemail.com wrote: On 16 July 2010 20:37, Don Stewart d...@galois.com wrote: chrisdone: Regarding the Haskell Platform, maybe a summer theme is in order? Sunrise, here's a whole platform upgrade. Get it while it's hot, etc. That's a great idea! :-) Maybe you could work on a theme like this. Probably OTT. http://imgur.com/NjiVh Just an idea. My Inkscape-fu is weak. Looks nice. I particularly like that the three text sections are more balanced (the current design is somewhat asymmetrical and busy on the right hand side). ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] in-equality type constraint?
Christopher Lane Hinson wrote: On Fri, 16 Jul 2010, Paul L wrote: Does anybody know why the type families only supports equality test like a ~ b, but not its negation? I would suggest that type equality is actually used for type inference, whereas proof of type inequality would have no consequence (that I can think of) for the compiler. Also, it's a lot easier to solve a system of constraints when you only have positive constraints. Adding negative constraints greatly complicates the solver. In many cases it's still doable, though the structure of types might pose some additional challenges above the usual ones. (And they're usually called disequality constraints, since inequalities are only interesting when you have subtyping.) -- Live well, ~wren ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
On 17 July 2010 01:43, Don Stewart d...@galois.com wrote: Here's a first cut in the repo with the new design converted to CSS http://code.haskell.org/haskell-platform/download-website/ If anyone would like to clean it up further, please send me patches to the style.css file or index.html. Wow, this is totally awesome! Excellent work! I darcs send'd you a tiny patch to make the download section more centered (it was offset on my screen res). Will submit more patches when I get home. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] in-equality type constraint?
On 07/17/2010 03:50 AM, Gábor Lehel wrote:
Does TypeEq a c HFalse imply proof of inequality, or unprovability
of equality?
Shouldn't these two be equivalent for types?
On Sat, Jul 17, 2010 at 2:32 AM, Steffen Schuldenzucker
sschuldenzuc...@uni-bonn.de wrote:
On 07/17/2010 01:08 AM, Paul L wrote:
Does anybody know why the type families only supports equality test
like a ~ b, but not its negation?
This has annoyed me, too. However, HList provides something quite similar,
namely the TypeEq[1] fundep-ed class which will answer type-equality with a
type-level boolean. (this is actually more powerful than a simple constraint,
because it allows us to introduce type-level conditionals)
To turn it into a predicate, you can use something like
(disclaimer: untested)
class C a b c where -- ...
-- for some reason, we can provide an instance C a b [c] *except* for
-- a ~ c.
instance (TypeEq a c x, x ~ HFalse) = a b [c] where -- ...
Best regards,
Steffen
[1]
http://hackage.haskell.org/packages/archive/HList/0.2.3/doc/html/Data-HList-FakePrelude.html#t%3ATypeEq
(Note that for it to work over all types, you have to import one of the
Data.HList.TypeEqGeneric{1,2} modules)
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Re: [Haskell-cafe] Re: Hot-Swap with Haskell
Brandon S Allbery KF8NH wrote:
On 7/16/10 05:21 , Andy Stewart wrote:
IMO, haskell interpreter is perfect solution for samll script job. But
i'm afraid haskell interpreter is slow for *large code*, i don't know,
i haven't try this way...
Hugs?
Or you can try implementing (or finding) a SASL interpreter[1]. SASL is
just the untyped[2] lambda calculus with named functions. ADTs are
implemented by function application, greatly simplifying the
compiler/interpreter. On their benchmarks, the version presented in the
paper is competitive with GHCi 6.4 and outperforms Hugs Jan2005.
Interpreting is always slower than compiled code. But how much that
matters is a separate issue. Folks seem to like their Perl, Python,
Ruby,... even for large projects.
[1] Jan Jansen (2005) /Data Types and Pattern Matching by Function
Application/, Proc. 17th IFL.
[2] The version they present in the paper uses the untyped calculus
since their pattern matching doesn't fit in Hindley--Milner. The problem
is the need for a fixpoint type operator, and polymorphism under the
fixpoint; thus, it fits perfectly fine in System F with iso-recursive
types. So just turn on -XRankNTypes and use them directly:
newtype List a = List { caseList
:: forall r. r - (a - List a - r) - r }
nil = List (\n c - n)
cons x xs = List (\n c - c x xs)
length xs = caseList xs 0 (\x xs' - 1 + length xs')
--
Live well,
~wren
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Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
On Sat, Jul 17, 2010 at 1:43 AM, Don Stewart d...@galois.com wrote: Here's a first cut in the repo with the new design converted to CSS http://code.haskell.org/haskell-platform/download-website/ If anyone would like to clean it up further, please send me patches to the style.css file or index.html. If the background is going to tile, it should be tileable. Other options are to have only a single image, centered; or, split the images into a left and right part, place those separately, and use a stretchable background in the center. --Max ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: in-equality type constraint?
Ryan Ingram wrote: But it doesn't generalize; you need to create a witness of inequality for every pair of types you care about. One can do better, avoiding the quadratic explosion. One merely needs to establish a map from a type to a suitable, comparable representation -- for example, to a type level list of type level numerals. Comparing types for equality, inequality and even order is a simple matter of comparing their representations. The fact that types become totally ordered lets us even implement type-level maps: Data.Map on types. (We may need a Type.* module hierarchy.) That idea was described in the HList paper http://homepages.cwi.nl/~ralf/HList/paper.pdf Section 9. The code is still available, http://code.haskell.org/HList/examples/TTypeable.hs see also TypeEqExplosive.hs, TypeEqTTypeable.hs. But given the use of UndecidableInstances and OverlappingInstances, I was hoping that type families could come a little cleaner. Normally if the use of functional dependencies requires UndecidableInstances, type families would ask for them too. As to OverlappingInstances -- that is the key to generic inequality, isn't it? Given the set of pairs of types, the set of the elements representing non-equal types is the complement of the set of elements representing equal types (by equal I mean identical). Overlapping instances is the way to express set complementation. The most general instance is chosen when none of the more specific apply. The set of types chosen by that general instance is the complement for the set of types chosen by the specific instances. Does TypeEq a c HFalse imply proof of inequality, or unprovability of equality? We are all constructivists here... If 'a' and 'c' are type variables, (TypeEq a c HFalse) is the constraint -- proof obligation if you will -- making sure the variables will never be instantiated to identical types. Strictly speaking, the constraint is discharged if 'a' and 'c' are two ground, and syntactically distinct (non-identical) types. In reality, I think GHC is able to discharge the constraint if 'a' and 'c' are grounded ``sufficiently enough'' for the difference to become apparent (e.g., the head constructors are different). ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
2010/7/17 Don Stewart d...@galois.com: Here's a first cut in the repo with the new design converted to CSS http://code.haskell.org/haskell-platform/download-website/ If anyone would like to clean it up further, please send me patches to the style.css file or index.html. I have big fonts (magnifyed by 3 or so in firefox) and it happens that text with Robust etc gets displayed over download icons. Other that that, it looks nice. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Christopher Done wrote: Maybe you could work on a theme like this. Probably OTT. http://imgur.com/NjiVh Just an idea. My Inkscape-fu is weak. I love the way he says my fu is weak after just posting a single image which is radically better than anything I have ever produced in 20+ years of doing computer graphics! o_O Anyway, I'm loving the current theme. But if we're redesigning the site, I'd like to repeat one request: Please, please, please make it easier to - Download older versions of HP. - Find out which HP release contains what. - Figure out what the difference between release X and release Y is. That is all. Thanks, Andrew. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Thomas Schilling wrote: It would be great if the new design were compatible with the new wiki design ( http://lambda-haskell.galois.com/haskellwiki/ ). It doesn't have to be *that* similar, just compatible. Hmm. That's really not very pretty... (Or maybe it's just that I dislike brown? I didn't like Ubuntu mainly because it's brown.) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Haters gonna hate. The new wiki will have a user preference to switch back to the default monobook style. You can always do that if you want. It doesn't work fully, yet, but that's on my ToDo list. On 17 July 2010 11:53, Andrew Coppin andrewcop...@btinternet.com wrote: Thomas Schilling wrote: It would be great if the new design were compatible with the new wiki design ( http://lambda-haskell.galois.com/haskellwiki/ ). It doesn't have to be *that* similar, just compatible. Hmm. That's really not very pretty... (Or maybe it's just that I dislike brown? I didn't like Ubuntu mainly because it's brown.) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- If it looks like a duck, and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family Anatidae on our hands. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Thomas Schilling wrote: Haters gonna hate. Well, I don't *hate* it. It just looks a little muddy, that's all. I tend to go for bright primary colours. But, as you say, each to their own... The actual layout isn't bad. A bit tall-and-thin, but otherwise OK. The new wiki will have a user preference to switch back to the default monobook style. You can always do that if you want. It doesn't work fully, yet, but that's on my ToDo list. Heh, well, maybe if we make half a dozen styles, there will be at least one that everyone is happy with. ;-) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
On 17 July 2010 13:37, Andrew Coppin andrewcop...@btinternet.com wrote: Thomas Schilling wrote: Haters gonna hate. Well, I don't *hate* it. It just looks a little muddy, that's all. I tend to go for bright primary colours. But, as you say, each to their own... The actual layout isn't bad. A bit tall-and-thin, but otherwise OK. The new wiki will have a user preference to switch back to the default monobook style. You can always do that if you want. It doesn't work fully, yet, but that's on my ToDo list. Heh, well, maybe if we make half a dozen styles, there will be at least one that everyone is happy with. ;-) Hi Andy, thanks for the kind words. Whether we like the default theme or not right now, I still think it's important that the first thing a newbie sees makes a good impression. The fact that you can change the default theme to something else is irrelevant. Personally I agree it's a bit Ubuntu without the modernness, it's more Age of Empires/CIV, we-do-archeology-with-our-italics-serif-font (I find it a chore to read, can't imagine what people who aren't native to the Latin character would think), and the Haskell logo is oddly placed so that it looks more like an advertisement, search should always be on the right hand side, navigation should really be on the left, putting on the right is iffy. I do like the orange links. But also if we liked it, regardless, we should do user testing (checkout Don't Make Me Think, Rocket Surgery Made Easy). Sadly nobody has the time nor inclination to do proper web development and actually test designs and get feedback, so I suppose we're working with the time we've got. At least with theme support, we can write a load of themes, and then perhaps do a vote on what people think makes the best impression as a default. That seems most efficient and fair. I'll certainly make a couple. Hats off to Thomas for implementing a more friendly theme. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Plotting Vectors with GnuPlot Wrapper
Maryam Moghadas schrieb: Hi When I use Vectors as a PlotStyle in Graphics.Gnuplot.Simple, the output curve.gp http://curve.gp and curve0.csv is not generated correctly. For example when I write in ghci: plotPathStyle [] (PlotStyle Vectors (DefaultStyle 1)) [(1,1),(2,7)] Yes, my wrapper could not handle this correctly. Please try the latest version from http://code.haskell.org/gnuplot/ and its advanced interface as demonstrated in http://code.haskell.org/gnuplot/src/Demo.hs You may also want to subscribe to http://projects.haskell.org/cgi-bin/mailman/listinfo/gnuplot/ ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
RE: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Hi Chris, I like it, I just have 2 small observations: 1. I don't think it's actually centered, on my resolution from the left to the The Haskell Platform is about 8 inches, but from the right to it is 11. My eyes just keep telling me something's wrong 2. Could you maybe update the windows flag from that xp flag to the current mate one? I think it would also look better on that design http://www.microsoft.com/presspass/images/gallery/logos/web/Windows_generic_v_web.jpg Or the current windows 7 flag http://www.microsoft.com/presspass/images/gallery/logos/web/Windows7_v_Web.jpg The colors I believe are much nicer on those. Regards, Phyx -Original Message- From: haskell-cafe-boun...@haskell.org [mailto:haskell-cafe-boun...@haskell.org] On Behalf Of Christopher Done Sent: Saturday, July 17, 2010 14:32 To: Andrew Coppin Cc: haskell-cafe@haskell.org Subject: Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site On 17 July 2010 13:37, Andrew Coppin andrewcop...@btinternet.com wrote: Thomas Schilling wrote: Haters gonna hate. Well, I don't *hate* it. It just looks a little muddy, that's all. I tend to go for bright primary colours. But, as you say, each to their own... The actual layout isn't bad. A bit tall-and-thin, but otherwise OK. The new wiki will have a user preference to switch back to the default monobook style. You can always do that if you want. It doesn't work fully, yet, but that's on my ToDo list. Heh, well, maybe if we make half a dozen styles, there will be at least one that everyone is happy with. ;-) Hi Andy, thanks for the kind words. Whether we like the default theme or not right now, I still think it's important that the first thing a newbie sees makes a good impression. The fact that you can change the default theme to something else is irrelevant. Personally I agree it's a bit Ubuntu without the modernness, it's more Age of Empires/CIV, we-do-archeology-with-our-italics-serif-font (I find it a chore to read, can't imagine what people who aren't native to the Latin character would think), and the Haskell logo is oddly placed so that it looks more like an advertisement, search should always be on the right hand side, navigation should really be on the left, putting on the right is iffy. I do like the orange links. But also if we liked it, regardless, we should do user testing (checkout Don't Make Me Think, Rocket Surgery Made Easy). Sadly nobody has the time nor inclination to do proper web development and actually test designs and get feedback, so I suppose we're working with the time we've got. At least with theme support, we can write a load of themes, and then perhaps do a vote on what people think makes the best impression as a default. That seems most efficient and fair. I'll certainly make a couple. Hats off to Thomas for implementing a more friendly theme. ___ Haskell-Cafe mailing list Haskell-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
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Have you got SVG or PNG versions of those logos? On 17 July 2010 14:54, Phyx loneti...@gmail.com wrote: Hi Chris, I like it, I just have 2 small observations: 1. I don't think it's actually centered, on my resolution from the left to the The Haskell Platform is about 8 inches, but from the right to it is 11. My eyes just keep telling me something's wrong 2. Could you maybe update the windows flag from that xp flag to the current mate one? I think it would also look better on that design http://www.microsoft.com/presspass/images/gallery/logos/web/Windows_generic_v_web.jpg Or the current windows 7 flag http://www.microsoft.com/presspass/images/gallery/logos/web/Windows7_v_Web.jpg The colors I believe are much nicer on those. Regards, Phyx -Original Message- From: haskell-cafe-boun...@haskell.org [mailto:haskell-cafe-boun...@haskell.org] On Behalf Of Christopher Done Sent: Saturday, July 17, 2010 14:32 To: Andrew Coppin Cc: haskell-cafe@haskell.org Subject: Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site On 17 July 2010 13:37, Andrew Coppin andrewcop...@btinternet.com wrote: Thomas Schilling wrote: Haters gonna hate. Well, I don't *hate* it. It just looks a little muddy, that's all. I tend to go for bright primary colours. But, as you say, each to their own... The actual layout isn't bad. A bit tall-and-thin, but otherwise OK. The new wiki will have a user preference to switch back to the default monobook style. You can always do that if you want. It doesn't work fully, yet, but that's on my ToDo list. Heh, well, maybe if we make half a dozen styles, there will be at least one that everyone is happy with. ;-) Hi Andy, thanks for the kind words. Whether we like the default theme or not right now, I still think it's important that the first thing a newbie sees makes a good impression. The fact that you can change the default theme to something else is irrelevant. Personally I agree it's a bit Ubuntu without the modernness, it's more Age of Empires/CIV, we-do-archeology-with-our-italics-serif-font (I find it a chore to read, can't imagine what people who aren't native to the Latin character would think), and the Haskell logo is oddly placed so that it looks more like an advertisement, search should always be on the right hand side, navigation should really be on the left, putting on the right is iffy. I do like the orange links. But also if we liked it, regardless, we should do user testing (checkout Don't Make Me Think, Rocket Surgery Made Easy). Sadly nobody has the time nor inclination to do proper web development and actually test designs and get feedback, so I suppose we're working with the time we've got. At least with theme support, we can write a load of themes, and then perhaps do a vote on what people think makes the best impression as a default. That seems most efficient and fair. I'll certainly make a couple. Hats off to Thomas for implementing a more friendly theme. ___ Haskell-Cafe mailing list Haskell-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
RE: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Wikipedia has both http://en.wikipedia.org/wiki/File:Windows_7_logo.svg I don't have an svg editor, but you'd have to remove the Windows 7 text, but that should be trivial. -Original Message- From: Christopher Done [mailto:chrisd...@googlemail.com] Sent: Saturday, July 17, 2010 14:58 To: Phyx Cc: Andrew Coppin; haskell-cafe@haskell.org Subject: Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site Have you got SVG or PNG versions of those logos? On 17 July 2010 14:54, Phyx loneti...@gmail.com wrote: Hi Chris, I like it, I just have 2 small observations: 1. I don't think it's actually centered, on my resolution from the left to the The Haskell Platform is about 8 inches, but from the right to it is 11. My eyes just keep telling me something's wrong 2. Could you maybe update the windows flag from that xp flag to the current mate one? I think it would also look better on that design http://www.microsoft.com/presspass/images/gallery/logos/web/Windows_ge neric_v_web.jpg Or the current windows 7 flag http://www.microsoft.com/presspass/images/gallery/logos/web/Windows7_v _Web.jpg The colors I believe are much nicer on those. Regards, Phyx -Original Message- From: haskell-cafe-boun...@haskell.org [mailto:haskell-cafe-boun...@haskell.org] On Behalf Of Christopher Done Sent: Saturday, July 17, 2010 14:32 To: Andrew Coppin Cc: haskell-cafe@haskell.org Subject: Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site On 17 July 2010 13:37, Andrew Coppin andrewcop...@btinternet.com wrote: Thomas Schilling wrote: Haters gonna hate. Well, I don't *hate* it. It just looks a little muddy, that's all. I tend to go for bright primary colours. But, as you say, each to their own... The actual layout isn't bad. A bit tall-and-thin, but otherwise OK. The new wiki will have a user preference to switch back to the default monobook style. You can always do that if you want. It doesn't work fully, yet, but that's on my ToDo list. Heh, well, maybe if we make half a dozen styles, there will be at least one that everyone is happy with. ;-) Hi Andy, thanks for the kind words. Whether we like the default theme or not right now, I still think it's important that the first thing a newbie sees makes a good impression. The fact that you can change the default theme to something else is irrelevant. Personally I agree it's a bit Ubuntu without the modernness, it's more Age of Empires/CIV, we-do-archeology-with-our-italics-serif-font (I find it a chore to read, can't imagine what people who aren't native to the Latin character would think), and the Haskell logo is oddly placed so that it looks more like an advertisement, search should always be on the right hand side, navigation should really be on the left, putting on the right is iffy. I do like the orange links. But also if we liked it, regardless, we should do user testing (checkout Don't Make Me Think, Rocket Surgery Made Easy). Sadly nobody has the time nor inclination to do proper web development and actually test designs and get feedback, so I suppose we're working with the time we've got. At least with theme support, we can write a load of themes, and then perhaps do a vote on what people think makes the best impression as a default. That seems most efficient and fair. I'll certainly make a couple. Hats off to Thomas for implementing a more friendly theme. ___ Haskell-Cafe mailing list Haskell-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
RE: [Haskell-cafe] ghc api printing of types
Hey Daniel, You were right, that is the correct way of doing it, I just found out the type I was trying to print didn't have the context at that level anymore, I had to look one position higher in the ast. Thanks, Phyx -Original Message- From: Daniel Gorín [mailto:dgo...@dc.uba.ar] Sent: Sunday, July 04, 2010 15:49 To: Phyx Cc: haskell-cafe@haskell.org Subject: Re: [Haskell-cafe] ghc api printing of types I believe the way is done in hint is something like this (untested): showType t = do -- Unqualify necessary types -- (i.e., do not expose internals) unqual - GHC.getPrintUnqual return $ GHC.showSDocForUser unqual (GHC.pprTypeForUser False t) -- False means 'drop explicit foralls' Hope that helps Daniel On Jul 4, 2010, at 8:36 AM, Phyx wrote: I was wondering how given a Type I can get a pretty printed type out of it. Im currently using showSDocUnqual . pprType . snd . tidyOpenType emptyTidyEnv But this has the problem that predicates dont get printed, anyone know how GHCi does this? Thanks, Phyx ___ Haskell-Cafe mailing list Haskell-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
Re: [Haskell-cafe] Small flexible projects a possible niche for Haskell - your statement, please...
On 16/07/10 05:41, Nick Rudnick wrote: In consequence, an 8-student-project with two B.Sc. theses is raised as a pilot to examine the possibilities of using Haskell in the combination small team with limited resources and experience in a startup setting - we want to find out whether Haskell can be an offer competitive whith languages like Ruby Co. in such a setting. I'm not sure exactly what you are asking, but I'm going to try to answer the question Does Haskell have a niche in small, flexible projects? I think the answer is a definite yes. I also think that Haskell can do great things in bigger projects as well, but successful technologies often start out with a niche that was previously poorly served, and then move out from there. Haskell developers generally start by writing down an axiomatic definition of the problem domain. To a developer raised in traditional top down development this looks like a jump into coding, and furthermore coding at the lowest level. In fact it is a foundation step in the architecture, because Haskell works well with a bottom up approach. The property that makes this work is composability, which says that you can take primitive elements and integrate them into bigger units without having to worry about mutual compatibility. A Haskell library will typically define a data type Foo and then have functions with types along the lines of mungFoo :: Something - Foo - Foo. This combinator style of library give you the basic building blocks for manipulating Foos, along with a guarantee that the output will always be a valid Foo. So you can build up your own applications that work at the Foo level rather than down in the coding level of flow control and updated variables like conventional programs. This lets domain experts read and comment on the code, which reduces defect rates a lot. But these combinator libraries are also highly reusable because they describe an entire domain rather than just being designed to fit a single application. So the best bet is to analyse a domain, write a combinator library that models the domain, and then produce a series of related programs for specific applications within that domain. That will let a small team be amazingly productive. Paul. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: in-equality type constraint?
Thanks a lot for the explanation. Do you think supporting type inequality test in type families would require UndecidableInstances? For the reason that wren ng thornton mentioned? On Sat, Jul 17, 2010 at 4:56 AM, o...@okmij.org wrote: Ryan Ingram wrote: But it doesn't generalize; you need to create a witness of inequality for every pair of types you care about. One can do better, avoiding the quadratic explosion. One merely needs to establish a map from a type to a suitable, comparable representation -- for example, to a type level list of type level numerals. Comparing types for equality, inequality and even order is a simple matter of comparing their representations. The fact that types become totally ordered lets us even implement type-level maps: Data.Map on types. (We may need a Type.* module hierarchy.) That idea was described in the HList paper http://homepages.cwi.nl/~ralf/HList/paper.pdf Section 9. The code is still available, http://code.haskell.org/HList/examples/TTypeable.hs see also TypeEqExplosive.hs, TypeEqTTypeable.hs. But given the use of UndecidableInstances and OverlappingInstances, I was hoping that type families could come a little cleaner. Normally if the use of functional dependencies requires UndecidableInstances, type families would ask for them too. As to OverlappingInstances -- that is the key to generic inequality, isn't it? Given the set of pairs of types, the set of the elements representing non-equal types is the complement of the set of elements representing equal types (by equal I mean identical). Overlapping instances is the way to express set complementation. The most general instance is chosen when none of the more specific apply. The set of types chosen by that general instance is the complement for the set of types chosen by the specific instances. Does TypeEq a c HFalse imply proof of inequality, or unprovability of equality? We are all constructivists here... If 'a' and 'c' are type variables, (TypeEq a c HFalse) is the constraint -- proof obligation if you will -- making sure the variables will never be instantiated to identical types. Strictly speaking, the constraint is discharged if 'a' and 'c' are two ground, and syntactically distinct (non-identical) types. In reality, I think GHC is able to discharge the constraint if 'a' and 'c' are grounded ``sufficiently enough'' for the difference to become apparent (e.g., the head constructors are different). -- Regards, Paul Liu Yale Haskell Group http://www.haskell.org/yale ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Webdesign for an open source project is pretty much doomed from the beginning. Design requires a few opinionated people rather than democracy. This is design is a result of a haskell-cafe thread which naturally involved a lot of bikeshedding. It has its flaws, but it's certainly better than the old design and I know of no programming language website that has a particular great design, either. Sure, there's always room for improvement. Usability tests would be nice, but they're also time consuming. Fighting CSS to do what you want it to and make it work on at least all modern browsers is annoying and a huge time sink as well. I put the search field on the right (it's not very useful anyway), but otherwise I disagree with your requested changes. I would be willing to consider a different background image if you send me one (I may play around with a few myself). The logo on the left is inspired by http://www.alistapart.com. It works quite well on pages that are not the home page. The main feature of the design is that it scales quite nicely to different screen sizes (on recent enough browsers) -- try resizing your window. Also note that the exact contents can be edited (and probably shoud be). / Thomas On 17 July 2010 13:31, Christopher Done chrisd...@googlemail.com wrote: On 17 July 2010 13:37, Andrew Coppin andrewcop...@btinternet.com wrote: Thomas Schilling wrote: Haters gonna hate. Well, I don't *hate* it. It just looks a little muddy, that's all. I tend to go for bright primary colours. But, as you say, each to their own... The actual layout isn't bad. A bit tall-and-thin, but otherwise OK. The new wiki will have a user preference to switch back to the default monobook style. You can always do that if you want. It doesn't work fully, yet, but that's on my ToDo list. Heh, well, maybe if we make half a dozen styles, there will be at least one that everyone is happy with. ;-) Hi Andy, thanks for the kind words. Whether we like the default theme or not right now, I still think it's important that the first thing a newbie sees makes a good impression. The fact that you can change the default theme to something else is irrelevant. Personally I agree it's a bit Ubuntu without the modernness, it's more Age of Empires/CIV, we-do-archeology-with-our-italics-serif-font (I find it a chore to read, can't imagine what people who aren't native to the Latin character would think), and the Haskell logo is oddly placed so that it looks more like an advertisement, search should always be on the right hand side, navigation should really be on the left, putting on the right is iffy. I do like the orange links. But also if we liked it, regardless, we should do user testing (checkout Don't Make Me Think, Rocket Surgery Made Easy). Sadly nobody has the time nor inclination to do proper web development and actually test designs and get feedback, so I suppose we're working with the time we've got. At least with theme support, we can write a load of themes, and then perhaps do a vote on what people think makes the best impression as a default. That seems most efficient and fair. I'll certainly make a couple. Hats off to Thomas for implementing a more friendly theme. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- If it looks like a duck, and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family Anatidae on our hands. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
On 17 July 2010 16:21, Thomas Schilling nomin...@googlemail.com wrote: Webdesign for an open source project is pretty much doomed from the beginning. Design requires a few opinionated people rather than democracy. This is design is a result of a haskell-cafe thread which naturally involved a lot of bikeshedding. It has its flaws, but it's certainly better than the old design and I know of no programming language website that has a particular great design, either. This is why I mentioned that with theme support, we can provide lots of alternatives and then vote on the best one. Like the logo. That's democracy. Sure, there's always room for improvement. Usability tests would be nice, but they're also time consuming. This is what I said: On 17 July 2010 13:31, Christopher Done chrisd...@googlemail.com wrote: Sadly nobody has the time nor inclination to do proper web development and actually test designs and get feedback, so I suppose we're working with the time we've got. On 17 July 2010 16:21, Thomas Schilling nomin...@googlemail.com wrote: Fighting CSS to do what you want it to and make it work on at least all modern browsers is annoying and a huge time sink as well. I don't know about that; Firefox, Chrome, Safari, Opera and IE8 are pretty much equivalent from a CSS2 stand-point. It's not like anything fancy is needed. On 17 July 2010 16:21, Thomas Schilling nomin...@googlemail.com wrote: I put the search field on the right (it's not very useful anyway), but otherwise I disagree with your requested changes. I wasn't requesting any changes, I was demonstrating that I could pick at parts of the design but in the end it's down to user testing: On 17 July 2010 13:31, Christopher Done chrisd...@googlemail.com wrote: But also if we liked it, regardless, we should do user testing (checkout Don't Make Me Think, Rocket Surgery Made Easy). Then I said no one's going to do user testing, so maybe a vote would be the best: On 17 July 2010 13:31, Christopher Done chrisd...@googlemail.com wrote: Sadly nobody has the time nor inclination to do proper web development and actually test designs and get feedback, so I suppose we're working with the time we've got. At least with theme support, we can write a load of themes, and then perhaps do a vote on what people think makes the best impression as a default. That seems most efficient and fair. I'll certainly make a couple. On 17 July 2010 16:21, Thomas Schilling nomin...@googlemail.com wrote: I put the search field on the right (it's not very useful anyway), but otherwise I disagree with your requested changes. But now you've put the login on the left, which should also be on the right: 1. https://github.com/ 2. http://ubuntuforums.org/ 3. http://www.reddit.com/ 4. http://www.amazon.com/ 5. http://en.wikipedia.org/wiki/Main_Page 6. http://www.youtube.com/ 7. http://www.facebook.com/ 8. http://twitter.com/ 9. http://www.myspace.com/ 10. http://www.ebay.com/ 11. http://wordpress.com/ 12. http://www.flickr.com/explore/ 13. http://dictionary.reference.com/ See how the login is always on the top right? It's a usability standard. You can see how the sites focused on searching (google, youtube, twitter, myspace, ebay) have the search bar in the middle, but the ones where searching is secondary is always on the right. Logo on the left, search and login on the right, menu on the top or the left (or on the right if you want to freak your visitors out). On 17 July 2010 16:21, Thomas Schilling nomin...@googlemail.com wrote: The logo on the left is inspired by http://www.alistapart.com. It works quite well on pages that are not the home page. The main feature of the design is that it scales quite nicely to different screen sizes (on recent enough browsers) -- try resizing your window. Also note that the exact contents can be edited (and probably shoud be). It actually fits in on A List Apart (same theme). But, again, these criticisms are academic; design it how you like. Once the new Wiki's up we can submit patches/modifications or different themes and vote. One easy way to do user testing which is actually useful is through a site like reddit or Hacker News. I got valuable feedback from Hacker News, because the people were my target audience, i.e., none-Haskellers: http://news.ycombinator.com/item?id=1393593 It's possible to use the same method for haskell.org. It just requires some follow through to actually do what people request. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] is this a bug ?
On Saturday 17 July 2010 05:39:00, gat...@landcroft.co.uk wrote: On Sat 17/07/10 04:17 , Alexander Solla a...@2piix.com sent: Why are you performing unsafe IO actions? They don't play nice with laziness. OK, fair cop, but without the unsafe IO action, it still misbehaves. http://hpaste.org/fastcgi/hpaste.fcgi/view?id=27650 Michael. Source-diving reveals: it's a bug. Text.Regex.Posix.ByteString.Lazy is just a thin wrapper around the strict variant, lazy ByteStrings are transformed into strict ones before the functions of Text.Regex.Posix.ByteString are called. To avoid copying twice, if the lazy ByteString does not end with a '\0', a '\0' is snoc'ed to the end before transforming to a strict ByteString. Thus the regexec of Text.Regex.Posix.ByteString takes slices of a longer ByteString than it should and no measures are taken to chop the trailing '\0' off again. A related problem is that ByteStrings (and Strings) may legitimately contain '\0's, but regex-posix (and probably [almost] all other regex packages) treats them as CStrings, so the regex functions will stop processing at the first '\0' (naturally, they call C) but on the Haskell side, that may be only a small part of the string. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 7/17/10 06:49 , Andrew Coppin wrote: I love the way he says my fu is weak after just posting a single image which is radically better than anything I have ever produced in 20+ years of doing computer graphics! o_O Don't conflate ability to operate a piece of software with ability to do graphical design. (I have no problem with the former but am lousy at the latter. :) Anyway, I'm loving the current theme. But if we're redesigning the site, I'd like to repeat one request: Please, please, please make it easier to - Download older versions of HP. - Find out which HP release contains what. - Figure out what the difference between release X and release Y is. +1 I'd consider this mandatory. It's amazing how many projects apparently *don't*. - -- brandon s. allbery [linux,solaris,freebsd,perl] allb...@kf8nh.com system administrator [openafs,heimdal,too many hats] allb...@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.10 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkxB1xIACgkQIn7hlCsL25V1jwCeMFCfmOYwbGdyG3aoRA2/pu0o 524AnROWgU59aqQn5A/zYbrQHvgk6O7t =CcUT -END PGP SIGNATURE- ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
Here's my take on the new design: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Brandon S Allbery KF8NH wrote: On 7/17/10 06:49 , Andrew Coppin wrote: I love the way he says my fu is weak after just posting a single image which is radically better than anything I have ever produced in 20+ years of doing computer graphics! o_O Don't conflate ability to operate a piece of software with ability to do graphical design. (I have no problem with the former but am lousy at the latter. :) Join the club. I've operated and built ray tracers, fractal generators and so forth, but when I want to actually draw something, I always end up staring at a blank screen thinking hmm, what might be cool? I have no idea how the professionals do this. Try drawing a cube and writing on it cornflakes. It looks rubbish, right? Now go to any shop that sells cornflakes... all the boxes look amazing, right? How the do they do that?? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
On 17 July 2010 18:18, Niemeijer, R.A. r.a.niemei...@tue.nl wrote: Here's my take on the new design: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm O, I like it! Nice one for building it. Would you consider doing a design for the Haskell web site based on this template? (MediaWiki, remember) Might I suggest making The Haskell Platform coloured in a shade of the blue you're using? What do you think? It might look too flat, I don't know. Nevermind. Anyway, fantastic! What does everyone else think? So we have: http://hackage.haskell.org/platform/ (Kudos to Don for coming up with the original design and content from nothing.) http://imgur.com/NjiVh = http://code.haskell.org/haskell-platform/download-website/ http://imgur.com/9LHvk.jpg = http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm I'm leaning towards Neimeijer's. By the way, what tools did you use to make this? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
On Jul 16, 2010, at 11:09 AM, Don Stewart wrote: If anyone is interested in a 2010.2 series design for the HP site, the repository containing the stylesheet is here: http://code.haskell.org/haskell-platform/ I like the content. The layout has some flaws when rendered on my environment (Safari 4, but with perhaps narrower than most peoples windows): * The background image tiled looks pretty bad - since I see repeats and it doesn't really tile. * The three columns at the bottom overlap! Perhaps this is a valid case for a table rather than three divs and CSS layout. * The word Download isn't actually part of the download link. Many people might think to click on the Download text itself. Can we make that a link that auto-detects your OS and redirects appropriately? On Jul 17, 2010, at 7:21 AM, Thomas Schilling wrote: Webdesign for an open source project is pretty much doomed from the beginning. Design requires a few opinionated people rather than democracy. Truer words were never spoken! Good web sites always proceed from a single graphic designer's vision. Great ones combine that with, tweaking after deployment based on log analysis and A/B testing. I saw we just appoint a short group of designers and let them at it, and deploy it, and then see how it fares! I nominate Thomas and Christopher! As for CSS wrangling, I've got a fair bit of experience at that. I've even done it in the context of MediaWiki themes(*). If anyone needs some help on that aspect, I'm volunteering. I'm pretty sure I could reproduce Christopher's image in XHTML/CSS if desired. - Mark Mark Lentczner http://www.ozonehouse.com/mark/ IRC: mtnviewmark (*) My work on http://www.contextfreeart.org/ involves getting MediaWiki (used for the download and documentation sections), phpBB (for formus), custom PHP (for the gallery), and static pages to all style identically with CSS. I think I mostly succeeded. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Thought I'd bring Neimeijer's design into the mix, because I think it's brilliant (and it's been built): (For some reason it didn't appear in this thread in my GMail inbox; perhaps the Subject field got altered. Posting this here incase it happened like that for everyone else so that we can continue the discussion within this thread.) On 17 July 2010 18:18, Niemeijer, R.A. r.a.niemei...@tue.nl wrote: Here's my take on the new design: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm ___ Haskell-Cafe mailing list Haskell-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
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
allbery: like to repeat one request: Please, please, please make it easier to - Download older versions of HP. - Find out which HP release contains what. - Figure out what the difference between release X and release Y is. +1 I'd consider this mandatory. It's amazing how many projects apparently *don't*. We can certainly continue to link to old versions, to the old contents.html and the changelogs, as is currently planned. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Don Stewart wrote: allbery: like to repeat one request: Please, please, please make it easier to - Download older versions of HP. - Find out which HP release contains what. - Figure out what the difference between release X and release Y is. +1 I'd consider this mandatory. It's amazing how many projects apparently *don't*. We can certainly continue to link to old versions, to the old contents.html and the changelogs, as is currently planned. And unlike previous releases, this one seems to have a changelog. (It's nontrivial comparing two Cabal files trying to figure out what changed!) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
markl: I like the content. The layout has some flaws when rendered on my environment (Safari 4, but with perhaps narrower than most peoples windows): * The background image tiled looks pretty bad - since I see repeats and it doesn't really tile. Yes, noted. * The three columns at the bottom overlap! Perhaps this is a valid case for a table rather than three divs and CSS layout. Agreed and implemented. That was easier! * The word Download isn't actually part of the download link. Many people might think to click on the Download text itself. Can we make that a link that auto-detects your OS and redirects appropriately? If someone has code for this? As for CSS wrangling, I've got a fair bit of experience at that. I've even done it in the context of MediaWiki themes(*). If anyone needs some help on that aspect, I'm volunteering. I'm pretty sure I could reproduce Christopher's image in XHTML/CSS if desired. Well, perhaps poke around here: http://code.haskell.org/haskell-platform/download-website/index.html http://code.haskell.org/haskell-platform/download-website/style.css It's a darcs repo, so darcs get http://code.haskell.org/haskell-platform/ will work. -- Don ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
andrewcoppin: Don Stewart wrote: allbery: like to repeat one request: Please, please, please make it easier to - Download older versions of HP. - Find out which HP release contains what. - Figure out what the difference between release X and release Y is. +1 I'd consider this mandatory. It's amazing how many projects apparently *don't*. We can certainly continue to link to old versions, to the old contents.html and the changelogs, as is currently planned. And unlike previous releases, this one seems to have a changelog. (It's nontrivial comparing two Cabal files trying to figure out what changed!) Actually, it just got trivial: $ diffcabal old-platform.cabal haskell-platform.cabal Cabal 1.8.0.2 - 1.8.0.6 QuickCheck 2.1.0.3 - 2.1.1.1 alex 2.3.2 - 2.3.3 array 0.3.0.0 - 0.3.0.1 base 4.2.0.0 - 4.2.0.2 bytestring 0.9.1.5 - 0.9.1.7 cabal-install 0.8.0 - 0.8.2 cgi 3001.1.7.2 - 3001.1.7.3 directory 1.0.1.0 - 1.0.1.1 extensible-exceptions Added: 0.1.1.1 fgl 5.4.2.2 - 5.4.2.3 filepath 1.1.0.3 - 1.1.0.4 ghc 6.12.1 - 6.12.3 happy 1.18.4 - 1.18.5 hpc 0.5.0.4 - 0.5.0.5 old-time 1.0.0.3 - 1.0.0.5 process 1.0.1.2 - 1.0.1.3 regex-base 0.93.1 - 0.93.2 regex-compat 0.92 - 0.93.1 regex-posix 0.94.1 - 0.94.2 stm 2.1.1.2 - 2.1.2.1 template-haskell 2.4.0.0 - 2.4.0.1 unix 2.4.0.0 - 2.4.0.2 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Cabal lib (Setup.hs), --package-db, --enable-shared, haskell platform
I accidentally found a rarely encountered omission in Cabal (the lib, because via Setup.hs) by building Haskell Platform as shared libs from source. It is rare because you have to use both --enabled-shared and --package-db=blah together to run into it. --package-db=blah is already rare enough (probably only Haskell Platform's build script uses it); --enable-shared is my addition to make it even rarer. (Also I have only tried this on linux x86 32-bit.) Following the essence of scripts/build.sh plus my own --enable-shared: Create an empty lookaside package database with: echo '[]' /tmp/lookaside Install a package X that depends only on base (say), ask for shared libs, register in /tmp/lookaside only: ./Setup configure --package-db=/tmp/lookaside \ --ghc-pkg-option=--package-conf=/tmp/lookaside \ --enable-shared ./Setup build ./Setup register --inplace Install another package Y that depends on base and X only (say), ask for shared libs. There is a problem now related to X known to /tmp/lookaside only, but not known to the global or the user database: ./Setup configure --package-db=/tmp/lookaside \ --ghc-pkg-option=--package-conf=/tmp/lookaside \ --enable-shared ./Setup build -v2 Now it bombs. As the verbose build messages show, there is no problem creating the static *.a version; it bombs when creating the shared *.so version, and it is because it can't find X, and it is because -package-conf=/tmp/lookaside is not given to ghc at the *.so stage. (Though, the *.dyn_o stage works correctly.) My current fix is: ./Setup configure --package-db=/tmp/lookaside \ --ghc-pkg-option=--package-conf=/tmp/lookaside \ --ghc-option=-package-conf=/tmp/lookaside \ --enable-shared I surely hope we no longer need --ghc-pkg-option and --ghc-option in a week! :) ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Cabal lib (Setup.hs), --package-db, --enable-shared, haskell platform
and I forgot to say the Cabal lib tried is already version 1.8.0.6 ghc is 6.12.3 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
RE: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
I still like the original design on http://imgur.com/NjiVh a lot better, It has a simple modern design to it in my opinion :) -Original Message- From: haskell-cafe-boun...@haskell.org [mailto:haskell-cafe-boun...@haskell.org] On Behalf Of Christopher Done Sent: Saturday, July 17, 2010 19:31 To: Mark Lentczner Cc: haskell-platf...@projects.haskell.org; haskell-cafe Cafe Subject: Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site Thought I'd bring Neimeijer's design into the mix, because I think it's brilliant (and it's been built): (For some reason it didn't appear in this thread in my GMail inbox; perhaps the Subject field got altered. Posting this here incase it happened like that for everyone else so that we can continue the discussion within this thread.) On 17 July 2010 18:18, Niemeijer, R.A. r.a.niemei...@tue.nl wrote: Here's my take on the new design: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm ___ Haskell-Cafe mailing list Haskell-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 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
RE: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
From: Christopher Done [chrisd...@googlemail.com] Sent: 17 July 2010 19:23 To: Niemeijer, R.A. Cc: haskell-cafe@haskell.org Subject: Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart) O, I like it! Nice one for building it. Would you consider doing a design for the Haskell web site based on this template? (MediaWiki, remember) Thanks. As for designing the Haskell web site: I don't have any experience with making templates for MediaWiki, but I can at least give it a try. Is there anywhere I can download an offline copy of the site so I can start experimenting? Might I suggest making The Haskell Platform coloured in a shade of the blue you're using? What do you think? It might look too flat, I don't know. Nevermind. That does indeed look better, thanks. I've updated the title on the live version. By the way, what tools did you use to make this? Photoshop for creating the concept and the images. Sublime Text for writing the html and css.___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
On Sat, Jul 17, 2010 at 2:23 PM, Christopher Done chrisd...@googlemail.com wrote: Anyway, fantastic! What does everyone else think? I like it as well. There are only two nitpicks: I think that icon for Linux is lame, and I get confused by the image of the guy diving. Thanks, =) -- Felipe. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] ANN: hledger 0.11
hledger 0.11 is released! Thanks to all testers and to Michael Snoyman for much help keeping up with Yesod. Best, -Simon home: http://hledger.org Release notes: 2010/07/17 hledger 0.11 * split --help, adding --help-options and --help-all/-H, and make it the default command * use journal instead of ledger file; default suffix is .journal, default file is ~/.journal * auto-create missing journal files rather than giving an error * new format-detecting file reader (mixed journal transactions and timelog entries are no longer supported) * work around for first real-world rounding issue (test zero to 8 decimal places instead of 10) * when reporting a balancing error, convert the error amount to cost * parsing: support double-quoted commodity symbols, containing anything but a newline or double quote * parsing: allow minus sign before commodity symbol as well as after (also fixes a convert bug) * parsing: fix wrong parse error locations within postings * parsing: don't let trailing whitespace in a timelog description mess up account names * add: allow blank descriptions * balance: --flat provides a simple non-hierarchical format * balance: --drop removes leading account name components from a -- flat report * print, register, balance: fix layout issues with mixed-commodity amounts * print: display non-simple commodity names with double-quotes * stats: layout tweaks, add payee/description count * stats: don't break on an empty file * stats: -p/--period support; a reporting interval generates multiple reports * test: drop verbose test runner and testpack dependency * web: a new web ui based on yesod, requires ghc 6.12; old ghc 6.10- compatible version remains as -fweb610 * web: allow wiki-like journal editing * web: warn and keep running if reloading the journal gives an error * web: --port and --base-url options set the webserver's tcp port and base url * web: slightly better browser opening on microsoft windows, should find a standard firefox install now * web: in a web-enabled build on microsoft windows, run the web ui by default Stats: 55 days and 136 commits since last release. Now at 5552 lines of code with 132 tests and 54% unit test coverage. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 7/17/10 13:23 , Christopher Done wrote: On 17 July 2010 18:18, Niemeijer, R.A. r.a.niemei...@tue.nl wrote: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm O, I like it! Nice one for building it. Would you consider doing a design for the Haskell web site based on this template? (MediaWiki, remember) +1 - -- brandon s. allbery [linux,solaris,freebsd,perl] allb...@kf8nh.com system administrator [openafs,heimdal,too many hats] allb...@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.10 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkxCKF0ACgkQIn7hlCsL25WoFgCaA6yNmPWbndzZ7ks7V4UfPKE5 gxgAnA9O3w7JUxVLg1+NmBqq8wsbykHF =A34Y -END PGP SIGNATURE- ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
On Sat, 17 Jul 2010 18:02:05 -0400 Brandon S Allbery KF8NH allb...@ece.cmu.edu wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 7/17/10 13:23 , Christopher Done wrote: On 17 July 2010 18:18, Niemeijer, R.A. r.a.niemei...@tue.nl wrote: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm O, I like it! Nice one for building it. Would you consider doing a design for the Haskell web site based on this template? (MediaWiki, remember) +1 +1 also but why is linux cross-eyed ? :-) Brian ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
Well, Linux fanboys are known for spending too much time with their computers compiling OS kernel or building world, no surprise their eyes aren't in place. On 18 Jul 2010, at 02:54, bri...@aracnet.com wrote: On Sat, 17 Jul 2010 18:02:05 -0400 Brandon S Allbery KF8NH allb...@ece.cmu.edu wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 7/17/10 13:23 , Christopher Done wrote: On 17 July 2010 18:18, Niemeijer, R.A. r.a.niemei...@tue.nl wrote: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm O, I like it! Nice one for building it. Would you consider doing a design for the Haskell web site based on this template? (MediaWiki, remember) +1 +1 also but why is linux cross-eyed ? :-) Brian ___ Haskell-Cafe mailing list Haskell-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
[Haskell-cafe] Best links for Haskell Platform distro packages?
Can distro maintainers confirm these are the best links for each distro package? Debian http://packages.debian.org/squeeze/haskell-platform (or should it be sid?) Fedora: https://admin.fedoraproject.org/pkgdb/acls/name/haskell-platform Gentoo: http://www.haskell.org/haskellwiki/Gentoo/HaskellPlatform NixOS: http://hydra.nixos.org/job/nixpkgs/trunk/haskellPackages_ghc6121.haskellPlatform2010100 OpenSUSE: https://build.opensuse.org/project/show?project=devel:languages:haskell ?? For Ubuntu, I find a few confusing things: Ubuntu: https://launchpad.net/ubuntu/+source/haskell-platform But nothing at: http://packages.ubuntu.com/lucid/haskell-platform But there's instructions for the src build: http://davidsiegel.org/haskell-platform-in-karmic-koala/ -- Don ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Best links for Haskell Platform distro packages?
Don Stewart d...@galois.com writes: Can distro maintainers confirm these are the best links for each distro package? [snip] Gentoo: http://www.haskell.org/haskellwiki/Gentoo/HaskellPlatform Ugh, that would be the right page if we bothered to keep it maintained. I might do so during the week, but yeah, use that page. -- Ivan Lazar Miljenovic ivan.miljeno...@gmail.com IvanMiljenovic.wordpress.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
Miguel Mitrofanov miguelim...@yandex.ru writes: Well, Linux fanboys are known for spending too much time with their computers compiling OS kernel or building world, no surprise their eyes aren't in place. That's just Gentoo fanboys, thank you very much. Stop trying to give the rest of the riff-raff our points of pride!!! -- Ivan Lazar Miljenovic ivan.miljeno...@gmail.com IvanMiljenovic.wordpress.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Design for 2010.2.x series Haskell Platform site
Andrew Coppin andrewcop...@btinternet.com writes: Anyway, I'm loving the current theme. But if we're redesigning the site, I'd like to repeat one request: Please, please, please make it easier to - Download older versions of HP. - Find out which HP release contains what. - Figure out what the difference between release X and release Y is. Shouldn't be there also an explanation of what happens if you have release X installed and later you install release Y (obviously, X Y)? Some of the worries an user can have: - if some program depends on having release X, would it still works with Y. - would the installation of Y replace X, or would I have both versions. This issue seems to be open [0]; some advice about what should be expected would be very nice. Best, Miguel. [0] http://trac.haskell.org/haskell-platform/ticket/46 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Best links for Haskell Platform distro packages?
Fedora: https://admin.fedoraproject.org/pkgdb/acls/name/haskell-platform Yes, thanks that is fine. Jens ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: unusual behavior from cabal
On 7/16/10 9:36 PM, Ivan Lazar Miljenovic wrote: Michael Litchardmich...@schmong.org writes: cabal: dependencies conflict: happstack-server-0.5.1 requires time ==1.1.4 however time-1.1.4 was excluded because happstack-server-0.5.1 requires time ==1.2.0.3 I did battle with this one today. Does adding --constraint 'convertible-text = 0.3.0.1' help ? ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Best links for Haskell Platform distro packages?
2010년 07월 17일 16:53, Don Stewart 쓴 글: Can distro maintainers confirm these are the best links for each distro package? Debian http://packages.debian.org/squeeze/haskell-platform (or should it be sid?) http://packages.debian.org/haskell-platform I am not a maintainer but I suggest the link above since it is the way to have them both, by searching package by package name. I believe haskell-platform package name is not likely to change. So, that URL will consistently serve the purpose even after major stable releases. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
Yes, but our freshly compiled binaries have far more nutrients then your factory produced ones! Besides, the world would be a far better place if everyone compiled local rather than having binaries shipped to them from half-way across the globe... On 7/17/10 4:08 PM, Miguel Mitrofanov wrote: Well, Linux fanboys are known for spending too much time with their computers compiling OS kernel or building world, no surprise their eyes aren't in place. On 18 Jul 2010, at 02:54, bri...@aracnet.com wrote: On Sat, 17 Jul 2010 18:02:05 -0400 Brandon S Allbery KF8NH allb...@ece.cmu.edu wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 7/17/10 13:23 , Christopher Done wrote: On 17 July 2010 18:18, Niemeijer, R.A. r.a.niemei...@tue.nl wrote: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm O, I like it! Nice one for building it. Would you consider doing a design for the Haskell web site based on this template? (MediaWiki, remember) +1 +1 also but why is linux cross-eyed ? :-) Brian ___ Haskell-Cafe mailing list Haskell-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 ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Handling absent maintainers
On Fri, Jul 16, 2010 at 10:54 AM, Mark Wotton mwot...@gmail.com wrote: Hello all, I've recently had problems with haskell-src-meta. While it's a great package, it doesn't currently compile on GHC 6.12, and Matt Morrow doesn't seem to be around to push the version that does to Hackage. Our one-world approach with cabal seems to discourage forking as a casual act, so when a package that others rely on goes AWOL, it's very awkward to fix it. I can think of a few ways to get around my current problems: 1. upload haskell-src-meta-placeholder, or haskell-src-meta-mwotton, or something similar - this could be said to pollute the namespace, but would solve my immediate problem. I'd have to similarly specialise the chain of packages up to the one I actually want to use as well, though. I've uploaded haskell-src-meta-mwotton, using the development version. It seems to work fine for my applications. It's a bit of a hack, but I can't think of a better way to do it for now. mark -- A UNIX signature isn't a return address, it's the ASCII equivalent of a black velvet clown painting. It's a rectangle of carets surrounding a quote from a literary giant of weeniedom like Heinlein or Dr. Who. -- Chris Maeda ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
Niemeijer, R.A. wrote: Here's my take on the new design: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm Is it just me, or does aligning [OSX,Win,Linux] `zip` [Comprehensive, Robust, CuttingEdge] send the wrong message... -- Live well, ~wren ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
wren: Niemeijer, R.A. wrote: Here's my take on the new design: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm Is it just me, or does aligning [OSX,Win,Linux] `zip` [Comprehensive, Robust, CuttingEdge] send the wrong message... Hah! ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
On Sat, 17 Jul 2010, wren ng thornton wrote: Niemeijer, R.A. wrote: Here's my take on the new design: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm Is it just me, or does aligning [OSX,Win,Linux] `zip` [Comprehensive, Robust, CuttingEdge] send the wrong message... I found it rather conspicuous that all three of the items listed under cutting edge (multicore parallelism, thread sparks, and transactional memory) fell into concurrency/parallelism category. I'm not saying it's a problem, or that I have a better idea, but are we conscious that we're doing it, and is it what we want? Friendly, --Lane ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] RE: Design for 2010.2.x series Haskell Platform site (Don Stewart)
wren ng thornton w...@freegeek.org writes: Niemeijer, R.A. wrote: Here's my take on the new design: Screenshot: http://imgur.com/9LHvk.jpg Live version: http://dl.dropbox.com/u/623671/haskell_platform_redesign/index.htm Is it just me, or does aligning [OSX,Win,Linux] `zip` [Comprehensive, Robust, CuttingEdge] send the wrong message... Yeah, I wouldn't exactly call Windows Robust... -- Ivan Lazar Miljenovic ivan.miljeno...@gmail.com IvanMiljenovic.wordpress.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Re: Best links for Haskell Platform distro packages?
Don Stewart d...@galois.com writes: For Ubuntu, I find a few confusing things: Ubuntu: https://launchpad.net/ubuntu/+source/haskell-platform But nothing at: http://packages.ubuntu.com/lucid/haskell-platform But there's instructions for the src build: http://davidsiegel.org/haskell-platform-in-karmic-koala/ I'm not an Ubuntu maintainer, but I have ported the packages from debian into a PPA for lucid. This is simpler than the src build, at least: https://launchpad.net/~justinbogner/+archive/haskell-platform ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] possible bug in default module lookup scheme / or invalid haskell?
Hello All, I'm not sure if this either a bug in how ghc does path/module lookup or it simply is invalid haskell: consider modules A, A.B and A.B.C where A imports A.B, and A.B imports A.B.C with the following file system layout A.hs A/B.hs A/B/C.hs minimal file examples: module A where import A.B testA = will it really really work? module A.B where import A.B.C testB = will it work - module A.B.C where testC = will this work? -- if i run ghci A.hs everything's fine but if in directory B i rune ghci B.hs, i get A/B.hs:2:8: Could not find module `A.B.C': Use -v to see a list of the files searched for. --- it seems to me that if the default search path for ghc(i) includes the current directory (which according to docs it does), this shouldn't be happening. (or is there some why this is good Behavior?) thanks! -Carter ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] possible bug in default module lookup scheme / or invalid haskell?
Carter Schonwald carter.schonw...@gmail.com writes: Hello All, I'm not sure if this either a bug in how ghc does path/module lookup or it simply is invalid haskell: consider modules A, A.B and A.B.C where A imports A.B, and A.B imports A.B.C with the following file system layout A.hs A/B.hs A/B/C.hs minimal file examples: module A where import A.B testA = will it really really work? module A.B where import A.B.C testB = will it work - module A.B.C where testC = will this work? -- if i run ghci A.hs everything's fine but if in directory B i rune ghci B.hs, i get A/B.hs:2:8: Could not find module `A.B.C': Use -v to see a list of the files searched for. --- it seems to me that if the default search path for ghc(i) includes the current directory (which according to docs it does), this shouldn't be happening. (or is there some why this is good Behavior?) I think ghci is just not smart enough to know that it should change to the parent directory and run it from there. As such, it's trying to find A.B.C from the context of the current directory, and the file is not in A/A/B/C.hs so it can't find it. So it's just a limitation of ghci (I think). -- Ivan Lazar Miljenovic ivan.miljeno...@gmail.com IvanMiljenovic.wordpress.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
