Re: [Haskell-cafe] Transforming a ADT to a GADT

2012-09-17 Thread Florian Lorenzen
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Thanks Oleg for this elaboration. I'm now happy with the solution involving an existential. I first did not realize that I still could apply functions of type `Term t - Term t` as soon as I open the package. On 09/15/2012 01:02 PM, o...@okmij.org

Re: [Haskell-cafe] Transforming a ADT to a GADT

2012-09-17 Thread Florian Lorenzen
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Thanks Erik. This made the issue clear to me. Best regards, Florian On 09/14/2012 03:22 PM, Erik Hesselink wrote: On Fri, Sep 14, 2012 at 2:27 PM, Erik Hesselink hessel...@gmail.com wrote: In general, I think you have to work inside an

Re: [Haskell-cafe] Transforming a ADT to a GADT

2012-09-17 Thread Florian Lorenzen
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 José, it occurs to me that with this solution, I always have to prescribe the type as in tc (Succ (Lit 5)) :: Maybe (Term Int) Otherwise, I obtain the message Ambiguous type variable `a0' in the constraint: (Tc a0) arising from a use of `tc'

Re: [Haskell-cafe] List indexer

2012-09-17 Thread Edgar Klerks
Hi I find it useful. I benchmarked it with criterion and your test file (see below) and it is a *lot* faster: warming up estimating clock resolution... mean is 3.776987 us (160001 iterations) found 887 outliers among 15 samples (0.6%) 662 (0.4%) high severe estimating cost of a clock

Re: [Haskell-cafe] Dynamic Programming with Data.Vector

2012-09-17 Thread Roman Leshchinskiy
Myles C. Maxfield wrote: Overall, I'm looking for a function, similar to Data.Vector's 'generate' function, but instead of the generation function taking the destination index, I'd like it to take the elements that have previously been constructed. Is there such a function? If there isn't

Re: [Haskell-cafe] Dynamic Programming with Data.Vector

2012-09-17 Thread Myles C. Maxfield
Aha there it is! Thanks so much. I didn't see it because it's under the Unfolding section instead of the Construction section. --Myles On Mon, Sep 17, 2012 at 6:07 AM, Roman Leshchinskiy r...@cse.unsw.edu.auwrote: Myles C. Maxfield wrote: Overall, I'm looking for a function, similar to

Re: [Haskell-cafe] guards in applicative style

2012-09-17 Thread Ryan Ingram
Not exactly what you asked for, but... filter (uncurry somePredicate) $ (,) $ list1 * list2 does the job. Using only applicative operations, it's impossible to affect the 'shape' of the result--this is the difference in power between applicative and monad. -- ryan On Wed, Sep 12, 2012

Re: [Haskell-cafe] Type error with Type families

2012-09-17 Thread Ryan Ingram
The problem is that the function 'element' is ambiguous, for the reasons MigMit pointed out. The standard solution to this problem is to add a dummy argument to fix the type argument to the type function: data Proxy a = Proxy class ... = ReplaceOneOf full where type Item full :: * --

Re: [Haskell-cafe] Type error with Type families

2012-09-17 Thread Alexander Solla
On Mon, Sep 17, 2012 at 10:59 AM, Ryan Ingram ryani.s...@gmail.com wrote: The problem is that the function 'element' is ambiguous, for the reasons MigMit pointed out. The standard solution to this problem is to add a dummy argument to fix the type argument to the type function: data Proxy

Re: [Haskell-cafe] Either Monad and Laziness

2012-09-17 Thread John Lato
Subject: Re: [Haskell-cafe] Either Monad and Laziness On 9/14/12 5:16 PM, Eric Velten de Melo wrote: But now I'm kinda lost. Is there an easy way to explain the difference between: -iteratee -conduit -enumerator I tend to group them into three families. 'iteratee' and 'enumerator' are

Re: [Haskell-cafe] What is the good way to work with list comprehension and UTCTime?

2012-09-17 Thread Magicloud Magiclouds
Thank you. Will do. On Mon, Sep 17, 2012 at 7:14 AM, Antoine Latter aslat...@gmail.com wrote: On Sun, Sep 16, 2012 at 5:04 PM, Richard O'Keefe o...@cs.otago.ac.nz wrote: On 15/09/2012, at 5:14 AM, Chris Heller wrote: You might want to have a look at the time-recurrence package:

[Haskell-cafe] [ANNOUNCE] Fmark markup language

2012-09-17 Thread José Lopes
Hello everyone, I just wanted to share a package I created called Fmark, now available on HackageDB. Feedback both on the project and on the code is greatly appreciated :) Fmark (Friendly Markup) is a very simple markup language without syntax and simple but sophisticated document styling,

Re: [Haskell-cafe] [ANNOUNCE] Fmark markup language

2012-09-17 Thread Kristopher Micinski
Jose, So I'm interested to hear you opinion on this as well... I use Pandoc with Markdown through Hakyll, which allows you to do a fair amount of cute things that are just really helpful for maintaining a blog (for example..). But I didn't get this from reading your github readme: what makes

Re: [Haskell-cafe] [ANNOUNCE] Fmark markup language

2012-09-17 Thread José Lopes
Hello Kris, Thank you for your email. At this moment, Fmark is not as powerful as Markdown, also because Fmark just started. Markdown offers things such as Blockquotes, Lists, Code blocks, links, emphasis, images, etc. Fmark does not offer as many features: for now, there are only

Re: [Haskell-cafe] [ANNOUNCE] Fmark markup language

2012-09-17 Thread Richard O'Keefe
On 18/09/2012, at 3:09 PM, José Lopes wrote: Fmark (Friendly Markup) is a very simple markup language without syntax and simple but sophisticated document styling, capable of producing PDF and XML files. Do you _really_ mean without syntax? Nope, thought not: Fmark relies merely on

[Haskell-cafe] Choosing color of the track

2012-09-17 Thread Manish Trivedi
Hi Folks, I am trying to plot two tracks with different colors. Following is my input file, -- 2012-09-18 00:10:48,166 @CurrentPerHour13057 Red 2012-09-18 00:10:48,166 =CurrentPerHour13057 0.0 2012-09-18 00:10:58,155 =CurrentPerHour13057 0.0 2012-09-18 00:11:08,203 =CurrentPerHour13057 0.0

Re: [Haskell-cafe] [ANNOUNCE] Fmark markup language

2012-09-17 Thread Ivan Lazar Miljenovic
On 18 September 2012 13:57, José Lopes jose.lo...@ist.utl.pt wrote: Hello Kris, Thank you for your email. At this moment, Fmark is not as powerful as Markdown, also because Fmark just started. Markdown offers things such as Blockquotes, Lists, Code blocks, links, emphasis, images, etc.

Re: [Haskell-cafe] [ANNOUNCE] Fmark markup language

2012-09-17 Thread Richard O'Keefe
On 18/09/2012, at 3:57 PM, José Lopes wrote: The problem with Fmark is also its greatest feature. While other markup languages introduce special syntactic characters to give meaning to the document's elements, I would like to take a different approach: I want to use characters that

Re: [Haskell-cafe] Choosing color of the track

2012-09-17 Thread Eugene Kirpichov
Hi, I'm the author and I'll reply tomorrow, sorry, going to sleep now :) thanks for the interest in the tools anyway! 17.09.2012, в 21:40, Manish Trivedi trivman...@gmail.com написал(а): Hi Folks, I am trying to plot two tracks with different colors. Following is my input file,