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Today's Topics:
1. Re: Simple function comparison (MJ Williams)
2. Re: ffi array and peekArray (PICCA Frederic-Emmanuel)
3. Re: is Haskell practical? (emacstheviking)
4. REPL with visualisation (Ondrej Nekola)
----------------------------------------------------------------------
Message: 1
Date: Thu, 26 Nov 2015 12:22:19 +0000
From: MJ Williams <matthewjwilliams...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] Simple function comparison
Message-ID: <5656f977.aa0bc30a.290ed.2...@mx.google.com>
Content-Type: text/plain; charset="us-ascii"; Format="flowed"
That's great, thanks.
Matt
At 11:53 26/11/2015, you wrote:
>On Thu, Nov 26, 2015 at 6:20 PM, MJ Williams
><<mailto:matthewjwilliams...@gmail.com>matthewjwilliams...@gmail.com> wrote:
>
>
>therefore f ( g a ) = g ( f a ) . (transitivity)
>
>
>If you're interested in getting a firm grasp of airtight proofs --
>with a view toward Haskell (and Agda and Idris) mastery -- you might
>want to pick and choose your way through the web-based proof exercises here:
>
><https://www.coursera.org/course/intrologic>https://www.coursera.org/course/intrologic
>
>This is a course firmly in the American analytic philosophy
>tradition, so Logic here is Symbolic Logic. Bonus: the course keeps
>AI and Machine Learning applications in the backdrop.
>
>It's unfortunate that it's some kind of well-kept secret.
>
>Those who don't need it -- because they've obtained the knowledge
>elsewhere -- won't know about it. And those who do want that
>knowledge also won't know about it.
>
>Did I mention the exercises are web-based? Yes, you get
>instantaneous feedback on whether you've got a correct proof or not.
>
>-- Kim-Ee
>_______________________________________________
>Beginners mailing list
>Beginners@haskell.org
>http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
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Message: 2
Date: Thu, 26 Nov 2015 12:50:49 +0000
From: PICCA Frederic-Emmanuel
<frederic-emmanuel.pi...@synchrotron-soleil.fr>
To: "The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell" <beginners@haskell.org>
Subject: Re: [Haskell-beginners] ffi array and peekArray
Message-ID:
<a2a20ec3b8560d408356cac2fc148e53b2fb7...@sun-dag3.synchrotron-soleil.fr>
Content-Type: text/plain; charset="Windows-1252"
Thanks a lot it works now :)
________________________________________
De : Beginners [beginners-boun...@haskell.org] de la part de Sylvain Henry
[hsy...@gmail.com]
Envoy? : dimanche 8 novembre 2015 21:45
? : The Haskell-Beginners Mailing List - Discussion of primarily beginner-level
topics related to Haskell
Objet : Re: [Haskell-beginners] ffi array and peekArray
You can alias HklFactory:
type HklFactory = Ptr ()
Or if you want to avoid mixing HklFactory and other pointers, you can use:
newtype HklFactory = HklFactory (Ptr ()) deriving (Storable)
The latter requires the GeneralizedNewtypeDeriving extension, see:
https://wiki.haskell.org/Foreign_Function_Interface#Renaming_and_Storable_instances
Sylvain
2015-11-08 21:30 GMT+01:00 PICCA Frederic-Emmanuel
<frederic-emmanuel.pi...@synchrotron-soleil.fr<mailto:frederic-emmanuel.pi...@synchrotron-soleil.fr>>:
Ok, so now I get this error
ghkl.hs:20:18:
No instance for (Foreign.Storable.Storable HklFactory)
arising from a use of ?peekArray?
In a stmt of a 'do' block: peekArray n factories
In the expression:
do { factories <- c_hkl_factory_get_all ptr;
n <- peek ptr;
peekArray n factories }
In the second argument of ?($)?, namely
?\ ptr
-> do { factories <- c_hkl_factory_get_all ptr;
n <- peek ptr;
.... }?
What should I do to create a Storable for HklFactory which is a simple pointer.
Thanks
Frederic
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------------------------------
Message: 3
Date: Thu, 26 Nov 2015 14:13:02 +0000
From: emacstheviking <obji...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] is Haskell practical?
Message-ID:
<caeieuuka6n0gqbhmkwotpeb5guw+fo49g+s7zajcnf7fa7w...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Matthew,
Agile is "just a process"... presumably it can deliver *anything* not just
software projects.
There's a lot of software people I know who look very surprised when you
tell them where and why "kanban" was developed!
Either way, Haskell isn't mainstream and sadly is unlikely to become so, at
leat not this century unless the educational system in the UK improves
markedly!
Let's just all use it when and where we can and keep spreading the word!
Sean.
On 26 November 2015 at 09:33, MJ Williams <matthewjwilliams...@gmail.com>
wrote:
> "lowest common denominator"
> Right on, Sean. That pretty much sums up the state of affairs.
> I would however say that the sort of culture, mindset, if you will,
> agile development encourages might not be entirely compatible with the
> thinking process and general view of the universe that FP requires. I
> could be mistaken on this entirely, but agile strikes me as something
> that would b much more at home in an essentially business-oriented
> environment used by people of that background e.g. people who thrive
> on using UML.
> Matthew
>
>
> On 26/11/2015, emacstheviking <obji...@gmail.com> wrote:
> > I read all the above. I have to agree with KC... I have been a software
> > developer for 30+ years now and I would dearly love to be able to use
> > Haskell in my day to day tasks when being paid. As an IT contractor in
> the
> > UK however that just isn't going to happen. By and large the management /
> > project planning mentality is "lowest common denominator" when it comes
> to
> > large IT projects. It's not hard to understand the reasons and from a
> > commercial and business perspective it makes sense, of course it does.
> >
> > I've been working on the UK MOT programme (now complete) for the last 18
> > months and it was all PHP, Zend Framework 2 and Doctrine because that
> skill
> > pool is huge compared to Haskell and when it comes to having a ready
> supply
> > of code capable meat-sacks to deliver stories on time, LCD is where it
> will
> > always be. TIOBE says that Java has been top dog for ever. I rest my
> case.
> >
> > Us in the haskell world realise that people that can use Haskell
> > effectively would be much more productive, and probably produce a lot
> more
> > functional(!) code in a shorter space of time, have a high sprint
> velocity,
> > deliver more stories etc. Quickcheck is inspired!
> >
> > The thought of being on an Agile team using haskell, wow, that's too much
> > to hope for...
> >
> > All the best,
> > Sean Charles
> >
> > On 25 November 2015 at 18:13, KC <kc1...@gmail.com> wrote:
> >
> >> Yes Haskell is practical except for finding Haskell replacement
> >> programmers.
> >>
> >> --
> >> --
> >>
> >> Sent from an expensive device which will be obsolete in a few months! :D
> >>
> >> Casey
> >>
> >> On Nov 25, 2015 9:50 AM, "Martin Vlk" <mar...@vlkk.cz> wrote:
> >>
> >>>
> >>>
> >>> Dennis Raddle:
> >>> > On Wed, Nov 25, 2015 at 4:56 AM, Alexander Berntsen <
> >>> alexan...@plaimi.net>
> >>> > wrote:
> >>>
> >>> <snip>
> >>>
> >>> > I don't agree. Having worked for 16 years in a government aerospace
> >>> > contractor doing C++ and Python programming, what I saw is that maybe
> >>> half
> >>> > the programmers struggled with precise thinking and abstraction. They
> >>> > thought of programs as step-by-step recipes and implemented those
> >>> recipes
> >>> > in exactly the same way they themselves had always thought about a
> >>> problem.
> >>> >
> >>> > Also having worked as a math tutor, I see many people who struggle
> >>> > with
> >>> > abstract thinking.
> >>>
> >>> <snip>
> >>>
> >>> > Can an "okay" imperative programmer become an "okay" Haskell
> >>> > programmer?
> >>> > Does the necessary skill, work, motivation, and talent to program at
> >>> > an
> >>> > "ordinary" imperative level serve as a sufficient prerequisite for
> >>> > functional programming? I really don't think so, but I could be
> wrong.
> >>>
> >>> What'd be the definition of an okay programmer? If we agree that's the
> >>> one that "learns how to solve a few standard problems and then applies
> >>> the same thing over and over without much creativity", then I'll argue
> >>> this will work with Haskell just like with any imperative language. If
> >>> you train them on Haskell that is. :-)
> >>>
> >>> <snip>
> >>>
> >>> > But I wonder if the same mechanisms that make Haskell concise (which
> >>> > are
> >>> > some of the things that make it hard) also are bound up with its
> >>> practical
> >>> > advantages so that they can't be separated.
> >>>
> >>> What you mean by practical? Does it mean that you can find enough
> people
> >>> able to use it in your real-world project, without putting too high
> >>> requirements on training them?
> >>>
> >>> If so, then we could say that given the current state of affairs, where
> >>> the mass of okay programmers are trained on a different paradigm,
> >>> Haskell is not all that practical.
> >>>
> >>> But if practical means that the language is well suited for solving
> >>> real-world problems, in beautiful ways, once you get it, then it is
> >>> uberpractical! :-)
> >>>
> >>> M.
> >>> _______________________________________________
> >>> Beginners mailing list
> >>> Beginners@haskell.org
> >>> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
> >>>
> >>
> >> _______________________________________________
> >> Beginners mailing list
> >> Beginners@haskell.org
> >> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
> >>
> >>
> >
> _______________________________________________
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Message: 4
Date: Fri, 27 Nov 2015 10:13:54 +0100
From: Ondrej Nekola <on...@nekola.cz>
To: beginners@haskell.org
Subject: [Haskell-beginners] REPL with visualisation
Message-ID: <56581ed2.8080...@nekola.cz>
Content-Type: text/plain; charset=utf-8; format=flowed
Hi
Just curious: is there some recommended "first choice" combination of
REPL and libs for (Apple) Swift styled "playgrounds"? (I have just seen
a fractalish coffee spill and remembered that I have not implemented
Mandelbrot set since high school and Pascal days and maybe it's time to
be a bit childish again).
Thanks
Ondra 'satai' Nekola
on...@nekola.cz
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