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Today's Topics:
1. Re: A first try (David Place)
2. Re: DSL for Android development (Sean Charles)
3. Re: Why aren't David Harley's QT bindings more popular?
(Kyle Murphy)
4. Re: DSL for Android development (Stephen Tetley)
5. Re: Why aren't David Harley's QT bindings more popular?
(Tom Murphy)
6. Creating beautiful code: can you make this
divide-and-conquer implementation of the "tails" function
beautiful? (Costello, Roger L.)
7. Re: Why aren't David Harley's QT bindings more popular?
(?ystein Kolsrud)
8. Re: DSL for Android development (Brandon Allbery)
----------------------------------------------------------------------
Message: 1
Date: Mon, 27 Jun 2011 14:34:40 -0400
From: David Place <[email protected]>
Subject: Re: [Haskell-beginners] A first try
To: [email protected]
Cc: Heinrich Apfelmus <[email protected]>,
[email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=us-ascii
On Jun 27, 2011, at 1:55 PM, Yitzchak Gale wrote:
> There's nothing to be embarrassed about. Haskell is lazy by default.
> That is certainly much different than what most people are
> used to. So it needs to be explained to beginners. It's the same
> for IO laziness as for pure laziness.
:-) It's not the difficulty of understanding laziness that I find
embarrassing. My Ph.D Computer Science friends that I have introduced Haskell
to understand that very well. It's their "You've got to be kidding" looks when
I tell them they have to call 'length' for effect or some such to get their
simple programs to work. They understand Lazy IO and think that it is broken.
:-)
____________________
David Place
Owner, Panpipes Ho! LLC
http://panpipesho.com
[email protected]
------------------------------
Message: 2
Date: Mon, 27 Jun 2011 19:52:02 +0100
From: Sean Charles <[email protected]>
Subject: Re: [Haskell-beginners] DSL for Android development
To: Mike Meyer <[email protected]>
Cc: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
On 27/06/11 18:47, Mike Meyer wrote:
> On Mon, 27 Jun 2011 15:04:55 +0100
> Sean Charles<[email protected]> wrote:
>
>> As a yet to be published iPhone hacker, now somewhat saddened by the
>> AppStore bouncers, I've turned to Android. I have a lot of Java and J2ME
>> experience but only eight months with Haskell. I hate java. The JVM is
>> awesome. Clojure is wish-fulfillment for Android right now.
> There are other choices. Have you looked into Scala or Groovy?
Yes. I learned them both about two years ago having at that point become
thoroughly peeved with "Java the language" and looking for other things.
I've kind of settled with Clojure if people want me to produce Java
applications purely out of personal choice as I know LISP and it felt
familiar.
>> So... where would be a good place to start with a DSL that could produce
>> Java code as its output? This is new to me! I've written simple lexers
>> and parsers and I know the ropes on that front but I don't know haskell
>> well enough yet to know how to go about it. I am thinking that I'd need
>> to create data types for the major classes, or maybe not, if i can
>> produce my own abstraction that generated multiple classes in the output
>> etc and so i descend into confusion about where to start!
> This seems like an odd approach.
Only if you consider my complete ignorance of DSL-s and how to 'do
them'. LMAO. This would be a personal 100% green-field venture,
ground-breaking, new territory, pioneering never done it before kind
of venture for me, to learn new tricks and things.
>> I did consider writing a "true" language that will code-generate
>> java instead of a DSL, that's still in my mind too.
> If by this, you mean generating JVM byte codes directly, I'd be
> interested in why this is a second choice behind generating Java?
> Generating JVM shouldn't be noticeably harder, should result in better
> code, can be moved to Android, and is the path taken by other
> languages running on the JVM.
>
> Sorry I can't help directly - but I'm also interested in Android
> development and hate Java (and find the infrastructure around it
> disappointing.)
>
I hadn't considered generating byte-codes!
I've used Jasmin in the past and I actually own a copy of the JVM book
from way back.
Now *that* would be interesting although Dalvik is slightly different in
what it accepts as byte codes I hear.
Strewth, the possibilities abound!
> <mike
------------------------------
Message: 3
Date: Mon, 27 Jun 2011 15:25:14 -0400
From: Kyle Murphy <[email protected]>
Subject: Re: [Haskell-beginners] Why aren't David Harley's QT bindings
more popular?
To: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset="utf-8"
The general consensus might be that "no-one wants gui libraries, as
everything can be done on the web", but I think that's idiotic. Aside from
e-mail, there's pretty much no "app" I use online but there are many desktop
applications I use on a day to day basis, most written in C or C++, and a
few written in Java, or Python. Various people have been claiming the death
of the desktop for well over 10 years now, but I don't see it happening
anytime soon. We've seen a lot of strong work going on in web-dev for
Haskell, particularly in things like Yesod and Snap, but Haskell GUI
development seems to be stagnating, and anytime anyone brings it up they get
told "no one does GUI development anymore", which is complete BS or this
issue wouldn't keep coming up. I've seen a few interesting GUI libraries,
but they all seem to have died out for one reason or another, and if
qtHaskell is actually being worked on and supported by someone I'd be very
interested in finding out more about it. It would also be nice if some of
the more interesting theoretical stuff like FRP could actually get a working
example built on top of one of the current generation GUI libraries (I've
looked at FRP a bit, but I don't really understand it, and I haven't found
any FRP libraries that still work).
-R. Kyle Murphy
--
Curiosity was framed, Ignorance killed the cat.
On Mon, Jun 27, 2011 at 08:45, Mats Rauhala <[email protected]> wrote:
> On 14:19 Mon 27 Jun , ?ystein Kolsrud wrote:
> > I haven't had a look at any of the other libraries out there, so I
> > don't really have much to compare with, but a problem with qtHaskell
> > is that it's usage is very non-functional in nature, and a lot of it's
> > C++ background shines through into the Haskell code (for instance
> > management of constructors/destructors). But on the whole I am pretty
> > happy with it.
>
> That seems to be quite common with haskell GUI libraries. Even GTK is
> extremly imperative by nature, almost clear mapping between the C
> version and the Haskell version. The general concensus seems to be that
> 'no-one wants gui libraries, as everything can be done on the web' :/.
>
> --
> Mats Rauhala
> MasseR
>
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://www.haskell.org/mailman/listinfo/beginners
>
>
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------------------------------
Message: 4
Date: Mon, 27 Jun 2011 20:55:14 +0100
From: Stephen Tetley <[email protected]>
Subject: Re: [Haskell-beginners] DSL for Android development
Cc: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=ISO-8859-1
On 27 June 2011 15:04, Sean Charles <[email protected]> wrote:
> So... where would be a good place to start with a DSL that could produce
> Java code as its output?
I think you might find you need a GPL (general purpose language) for
Android development rather than a DSL...
As a language, Scheme is roughly small enough that a Scheme compiler
can retargetted to other hosts (e.g. generate JVM bytecode rather than
native assembler or portable C). It would be possible to do this for
Glasgow Haskell, but pragmatically there probably isn't much will - it
would be a substantial engineering effort.
------------------------------
Message: 5
Date: Mon, 27 Jun 2011 15:55:46 -0400
From: Tom Murphy <[email protected]>
Subject: Re: [Haskell-beginners] Why aren't David Harley's QT bindings
more popular?
To: Kyle Murphy <[email protected]>
Cc: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=ISO-8859-1
>> On 14:19 Mon 27 Jun , ?ystein Kolsrud wrote:
[...]
>>The general concensus seems to be that
>> 'no-one wants gui libraries, as everything can be done on the web' :/.
On 6/27/11, Kyle Murphy <[email protected]> wrote:
> The general consensus might be that "no-one wants gui libraries, as
> everything can be done on the web", but I think that's idiotic. [...]
A lot of us talked about Haskell and GUI recently
(http://www.haskell.org/pipermail/haskell-cafe/2011-May/thread.html#91991).
It's far from consensus that we should let GUI languish, in favor of
the web.
Tom
------------------------------
Message: 6
Date: Mon, 27 Jun 2011 16:30:47 -0400
From: "Costello, Roger L." <[email protected]>
Subject: [Haskell-beginners] Creating beautiful code: can you make
this divide-and-conquer implementation of the "tails" function
beautiful?
To: "[email protected]" <[email protected]>
Message-ID:
<[email protected]>
Content-Type: text/plain; charset="us-ascii"
Hi Folks,
Below is a divide-and-conquer implementation of the "tails" function.
Notice the two patterns (x:y:xs) and (x:[]). And notice that (x:y:xs) is used
by the "length" function and again by the "splitAt" function. That doesn't seem
elegant. Can the function be simplified and made beautiful?
/Roger
tails' :: [a] -> [[a]]
tails' (x:y:xs) = map (++zs) (tails' ys) ++ tails' zs
where m = length (x:y:xs)
n = m `div` 2
(ys,zs) = splitAt n (x:y:xs)
tails' (x:[]) = [[x]]
------------------------------
Message: 7
Date: Mon, 27 Jun 2011 22:39:37 +0200
From: ?ystein Kolsrud <[email protected]>
Subject: Re: [Haskell-beginners] Why aren't David Harley's QT bindings
more popular?
To: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=ISO-8859-1
I'm not sure to what degree qtHaskell is being worked on at the
moment, but David Harley did answer some questions of mine per email
so at least there is some level of support for it.
/?ystein Kolsrud
On Mon, Jun 27, 2011 at 9:25 PM, Kyle Murphy <[email protected]> wrote:
> The general consensus might be that "no-one wants gui libraries, as
> everything can be done on the web", but I think that's idiotic. Aside from
> e-mail, there's pretty much no "app" I use online but there are many desktop
> applications I use on a day to day basis, most written in C or C++, and a
> few written in Java, or Python. Various people have been claiming the death
> of the desktop for well over 10 years now, but I don't see it happening
> anytime soon. We've seen a lot of strong work going on in web-dev for
> Haskell, particularly in things like Yesod and Snap, but Haskell GUI
> development seems to be stagnating, and anytime anyone brings it up they get
> told "no one does GUI development anymore", which is complete BS or this
> issue wouldn't keep coming up. I've seen a few interesting GUI libraries,
> but they all seem to have died out for one reason or another, and if
> qtHaskell is actually being worked on and supported by someone I'd be very
> interested in finding out more about it. It would also be nice if some of
> the more interesting theoretical stuff like FRP could actually get a working
> example built on top of one of the current generation GUI libraries (I've
> looked at FRP a bit, but I don't really understand it, and I haven't found
> any FRP libraries that still work).
>
> -R. Kyle Murphy
> --
> Curiosity was framed, Ignorance killed the cat.
>
>
> On Mon, Jun 27, 2011 at 08:45, Mats Rauhala <[email protected]> wrote:
>>
>> On 14:19 Mon 27 Jun ? ? , ?ystein Kolsrud wrote:
>> > I haven't had a look at any of the other libraries out there, so I
>> > don't really have much to compare with, but a problem with qtHaskell
>> > is that it's usage is very non-functional in nature, and a lot of it's
>> > C++ background shines through into the Haskell code (for instance
>> > management of constructors/destructors). But on the whole I am pretty
>> > happy with it.
>>
>> That seems to be quite common with haskell GUI libraries. Even GTK is
>> extremly imperative by nature, almost clear mapping between the C
>> version and the Haskell version. The general concensus seems to be that
>> 'no-one wants gui libraries, as everything can be done on the web' :/.
>>
>> --
>> Mats Rauhala
>> MasseR
>>
>> _______________________________________________
>> Beginners mailing list
>> [email protected]
>> http://www.haskell.org/mailman/listinfo/beginners
>>
>
>
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://www.haskell.org/mailman/listinfo/beginners
>
>
--
Mvh ?ystein Kolsrud
------------------------------
Message: 8
Date: Mon, 27 Jun 2011 17:34:45 -0400
From: Brandon Allbery <[email protected]>
Subject: Re: [Haskell-beginners] DSL for Android development
To: Stephen Tetley <[email protected]>
Cc: [email protected]
Message-ID: <[email protected]>
Content-Type: text/plain; charset=UTF-8
On Mon, Jun 27, 2011 at 15:55, Stephen Tetley <[email protected]> wrote:
> can retargetted to other hosts (e.g. generate JVM bytecode rather than
> native assembler or portable C). It would be possible to do this for
> Glasgow Haskell, but pragmatically there probably isn't much will - it
> would be a substantial engineering effort.
I think someone's already working on it. The backend work that makes
it possible is also why GHC can produce LLVM code, but I think that
was actually a "let's see if this works" with the new backend that was
designed to support targeting the JVM, CLR, Dalvik, etc.
--
brandon s allbery ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? [email protected]
wandering unix systems administrator (available) ? ? (412) 475-9364 vm/sms
------------------------------
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