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<p class=MsoPlainText>> Actually I stopped bothering long ago about
'understanding monads'.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>I think that's a shame, because when I wrote the source
code myself to get from a pure functional approach (passing the
"object" from function to function as an extra argument) to a monadic
approach, it was a real eye opener. Many of the different FP techniques, like <a
href="http://www.haskell.org/haskellwiki/Partial_application">partial
application</a>, <a href="http://www.haskell.org/haskellwiki/Parameter_order">reversed'
parameter order</a>, <a
href="http://www.haskell.org/haskellwiki/Anonymous_function">lambas</a>, <a
href="http://haskell.org/haskellwiki/Pointfree">pointfree notation</a> etc were
required to do this, which might be one of the reasons it’s a bit difficult for
newbies to see how a monad is just pure FP in disguise. After cracking the code
myself, I had so much appreciation for the guys who invented this stuff, it’s really
the work of a genius, at least that's the way it felt to me. And then the math
approach to abstract the whole thing into a type class, so it can be used for many
other "single-flow" (or how should I call that?) computations,... so
nice. I can’t say that I can write a monad instance myself yet without peeking
in the book, but I think I would recognize the pattern if I see code that could
make use of monads (at least the simple cases).<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Now I'm figuring out arrows, and this gives me a feeling
like... euh... well... it's even more abstract, it encapsulates any kind of
computation, also the ones then can be "split into multiple branches"
(okay, I should not talk about this, I don't really get arrows yet...)<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Of course, I'm a kind of guy who likes to understand the
inner details before I'm really pleased... So for Haskell, I still have a long way
to go :)<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>But you seem to be much further ahead than I am when it
comes to *using* monads, so your approach is probably better. Just get used to
the damn things and accept them (ouch, that feels a lot like religion...)<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Cheers,<o:p></o:p></p>
<p class=MsoPlainText>Peter<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>-----Original Message-----<br>
From: dav.vire@gmail.com [mailto:dav.vire@gmail.com] On Behalf Of david48<br>
Sent: Monday, October 15, 2007 9:15 AM<br>
To: bf3@telenet.be<br>
Cc: jerzy.karczmarczuk@info.unicaen.fr; haskell-cafe@haskell.org<br>
Subject: Re: [Haskell-cafe] do<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>On 10/14/07, Peter Verswyvelen <bf3@telenet.be>
wrote:<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>> If you want I can dig up my old source code where I
converted a random number<o:p></o:p></p>
<p class=MsoPlainText>> generator from a purely functional approach to a
monadic approach, but I'm not<o:p></o:p></p>
<p class=MsoPlainText>> sure reading it would help you, it's creating the
code yourself that will be useful I<o:p></o:p></p>
<p class=MsoPlainText>> guess.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Actually I stopped bothering long ago about
'understanding monads'.<o:p></o:p></p>
<p class=MsoPlainText>After reading many blog posts, wikis, tutorials, etc,
often multiple<o:p></o:p></p>
<p class=MsoPlainText>times, I developped a fuzzy idea of what you can do using
monads, and<o:p></o:p></p>
<p class=MsoPlainText>that's enough for me to use monads like IO, STM, State,
Parsec, etc.<o:p></o:p></p>
<p class=MsoPlainText>without too much problems.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>I use haskell to solve many little problems in my job and
I'm damned<o:p></o:p></p>
<p class=MsoPlainText>sad that I can't use it for larger projects.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>I feel I'm still a long way from identifying a situation
where I would<o:p></o:p></p>
<p class=MsoPlainText>need to write my own monad, and be able to do it, but by
the time such<o:p></o:p></p>
<p class=MsoPlainText>situation arises, I don't think it'd be too much a
problem.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>That being said, I plead guilty of not provinding feeback
where I<o:p></o:p></p>
<p class=MsoPlainText>found the doc lacking.<o:p></o:p></p>
<p class=MsoPlainText>I have no excuse.<o:p></o:p></p>
<p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p>
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