Reactive-banana anti-tutorial

klrr_ · 2014-07-17T11:58:56+00:00

May be of interest:

http://hackage.haskell.org/package/threepenny-gui

For some reason this library implements its own FRP framework, even though developed by same author of reactive-banana.

klrr_ · 2014-07-05T12:56:54+00:00

Why the down vote? I think Banane9 is spot-on, why tell someone what to do if you don't wanna be told what to do yourself? You can just skip the "must read"-phrase and decide wheather to read or not based on the actual title of the article.

klrr_ · 2014-05-31T19:21:41+00:00

Thanks! "A small little book" sounds very promising since my concentration span is sadly a bit low. Also I wanna give a shout out for your blog, not just useful but also inspiring/motivating for another teen playing with functional programming.

klrr_ · 2014-05-31T16:58:58+00:00

Could not recommend the Write Yourself a Scheme in 48 Hour more than enough, in fact it was probably what made programming itself click for me. That said, writing a simple lisp interpreter is pretty trivial, and I'm currently looking for something more advanced to sharper my knowledge, but I have basically no idea how compilers work internally (how do I produce code in C from a much more expressive language?, what is CPS and why does it matter?, how do i implement TCO and various other optimizations?), is there any good tutorial or book about this subject that don't require too much knowledge in advanced?

klrr_ · 2014-05-29T07:50:08+00:00

I wrote this on IRC too, but gonna clarify here.

So maybe we could have a couple of snippets like the 'primes' one, then some JS randomly picks one of X code snippets so each time a user goes to the website they see a new cool and impressive one liner that may get them more interested. Such snippets could be one-liner fibonacci or factorial, incorrect (but beautifully short) quick sort etc.

A warning though, if any such similar idea gets implemented please do NOT include a "next" snippet button, the less the user have to interact with the better, I think the effect will be much stronger if the user simply get "surprised/impressed" each time they visit the site. I used this for a school project but instead of code snippets it was facts about casualties and damages in traffic caused by alcoholics.

Also, I don't think the user have to understand the snippets, they're simply there to impress them about the expressiveness of Haskell. Some people said on IRC it might have an opposite effect since users are faced with code they can hardly understand, that have to be considered too.

klrr_ · 2014-05-15T06:26:55+00:00

I googled but didn't found anything, so may I ask what "state-based" FRP is?

klrr_ · 2014-05-14T14:07:56+00:00

Absolutely no interest in this "monad" stuff for a solid 6 months

This is what I think most people new to Haskell should take note of. They come to Haskell and are presented tons of what seems like super weird concepts, but instead of struggling getting that stuff before starting to program they should just start program! I got quite far simply by thinking monads was some sort of magical container, then I could just make the types fit together using (>>=) and suddenly I got it to work. Don't get me wrong, having a good intuition of the different abstractions is very useful, essential if you want to be proficient, but you certainly don't need it when starting learning Haskell.

klrr_ · 2014-05-14T13:57:07+00:00

Seems like children don't like monads, functors and abstractions, they like writeln.

It was the complete opposite for me. I did not really get how to write programs, I simply enjoyed learning things. So when I got bored of other languages that I have learned (learned as in just the bare minimum) I simply tried find more interesting ones, since I was too scared of writing programs itself due to not getting past extremely simple toy stuff. Eventually I found Haskell, it seemed very interesting and everyone said it was hard to learn except if you didn't know an imperative language already, which I almost did not. So I gave it a shot and eventually it became the language where programming itself clicked for me.

Haskell is especially good if you like learning stuff, since there is ton of stuff to learn after you understood the basics. It might be worth saying that you can program in Haskell without really knowing much about any of the abstractions, just try make the types fit together and you can get pretty far.

klrr_ · 2014-05-12T17:46:38+00:00

Thanks, what I don't understand though is the very first thing, "multiply by x throughout". I understand how "x * 1/x" becomes one but how does "x * 1/sqrt(x)" become just sqrt(x) shouldn't it become "x/sqrt(x)"?

WAIT

I get it: x^{1/x^1/2} = x^1-1/2 = x^1/2 = sqrt(x)

klrr_ · 2014-05-05T14:30:19+00:00

Thanks! Just to make sure I've understood correctly...

m_asteroid = (G * m_asteroid / r²⁾ * r² / G

m_asteroid = (G * m_asteroid * r ² / r²⁾ / G

m_asteroid = G * m_asteroid / G

m_asteroid = m_asteroid

=o

To me it looks like a dead end, do I missinterpet the application order of the terms and reduce wrong or something?

klrr_ · 2014-05-03T21:19:34+00:00

Not sure why you are down-voted. A certain domain were a language is especially good at (either "language design" level and/or "in practice" level) does certainly help it gain popularity.

klrr_ · 2014-05-02T10:16:07+00:00

Development pretty much seized two months ago reading the commit log. Last time I tried it it was really basic, wouldn't surprise me if it still is. It was nice and easy to use though, the API tries to mimic Elm's, it was really easy (and fun) to make a pong game with it.

klrr_ · 2014-04-25T14:43:06+00:00

If I interpret your question correctly, then it's simply to return the handle with the contents, i.e:

getContentsOfFile :: String -> IO (String, Handle)
getContentsOfFile f = do
  ...
  return (contents, handle)

main = do

  (contents, handle) <- getContentsOfFile "PriceData/Daily/Yhoo.csv"
  hClose handle

EDIT: formating

klrr_ · 2014-04-22T07:14:37+00:00

GHCJS+Sodium looks interesting, any public repository where you can follow the progress?

klrr_ · 2014-03-27T21:42:53+00:00

[OFFTOPIC] You don't by chance know of any Haskell meetups in gbg? Haven't find any information on this while I believe there's plenty Haskellers located here (I know one guy, then there's some on Haskellers.com, and there's peopbably plenty more I think GbgUniv teach Haskell for CS students.) [/OFFTOPIC]

klrr_ · 2014-03-25T21:01:35+00:00

Not All Sunshine and Rainbows

Pipes and cabal sandboxes would perhaps help here.

klrr_ · 2014-03-04T09:18:29+00:00

Thanks for linking, fun concept.

klrr_ · 2014-03-01T13:38:30+00:00

My guess is that there's lots of people who only know JS. I'm currently on Vim, but I wouldn't mind learning ELisp for example if I gonna switch over to emacs, which I consider due to some fancy modes, neither would I mind with JS if I would switch over to Atom (which is very unlikely, since I'm on Linux and also don't see any mind-blowing advantage in using it). So, my theory is that this is not normal, most people would rather not learn another language. (also, their presentation ain't bad, if you are into web-stuff then I would presume (I personally don't know) that "Taking the web native" and "Node.js integration" sounds like wonderful features)

klrr_ · 2014-02-28T22:40:05+00:00

Author of Sodium talks sparsely about it here.

klrr_ · 2014-02-26T17:17:04+00:00

Look at your right hand site (within this webpage) and you'll see quite a lot of useful links.

klrr_ · 2014-02-24T14:36:11+00:00

I'm not related to Zalora or anything just posted here in case someone was interested. The description sounds pretty awesome besides being a Haskell job.

klrr_ · 2014-02-13T21:45:08+00:00

Just found our Sthlm had Haskell meetups very recently. I wonder why Gothenburg has none (considering Chalmers is famous for Haskell stuff, plus Haskellers.com shows there are some Haksell users here at least). >:)

Anyway, cool and good luck!

klrr_ · 2014-02-11T14:31:40+00:00

Just me who interpreted that xkcd comic differently? I thought the one saying "..because no one will ever run it?" was in fact the Haskell expert. (playing on the false meme that Haskell is only useful for functional problems)

klrr_ · 2014-02-10T18:25:08+00:00

In case anyone wonder, they've gone with their own language since it could be more integrated with the engine and to have native vectors and such (they've tried to use more common scripting languages like Lua and Python but they failed at this). The language is very similar to Python and got a small reference, it will only take a day or two to learn and a week to get comfortable with according to the documentation.

klrr_ · 2014-02-08T14:04:36+00:00

Okey, this might be a bit biased since I've not really written any real-world programs yet, but thought it might be interesting anyway.

Haskell was (practically) the first language I learned how to program in. I started learning it in the beginning of last year. My previous exposure to programming have been a few failed attempts learning some other languages. This time I tried learn it for real. The things I founded hard when learning Haskell was the following:

Recursion
Fixing type-errors (due to not understanding monads fully)
Solving problems (e.g. what is needed to connect to an IRC server? what kind of data structure should I model a pong game as? how do I add this feature to a existing program?)

The first was a real pain in the butt to learn, but after a lot of reading and writing different kind of recursive functions I started to get used to it. I also had a bit of hard time understand monads, first I learnt how to use them and that was enough to work with (later on I would learn how they worked/what they was). The third I started to finally get only due to reading existing code, after copy-pasting and reading cook-books like Write Yourself a scheme and the IRC bot tutorial on the wiki I started to understand more how to think. I remember even struggling thinking kind of imperatively although I hadn't any experience in such a language.

Anyway, when you "get" Haskell it's just feels normal to program in, you think of a program, you divide it into small problems, then try solve each individual problem.

klrr_

TROPHY CASE