[Haskell-cafe] New slogan for haskell.org

[jerzy.karczmarczuk at info.unicaen.fr]

Andrew Coppin writes: 

> Dan Weston wrote:
>>   [...] and facilitates "borrow-from-the-future" techniques where useful 
>> with infinite data structures or recursive algorithms.
> 
> And this, gentlemen, is just one of the reasons why Haskell gets labelled 
> as "scary". 
> 
> It's very hard to explain what this enigmatic riddle-like statement 
> actually *means* without a very long exposition. (Heck, *I* haven't worked 
> out how to "borrow from the future" yet...)

Scary - schmary... 

If you want to be afraid of, say, Santa Claus, that's OK, you are a free
man. But, perhaps before saying that you haven't worked out something,
*try* to work it out. 

Read something about Richard Bird's circular programs. A nice Web article
(Lloyd Allison) is here: 

http://www.csse.monash.edu.au/~lloyd/tildeFP/1989SPE/ 

A really complicated application by Janis Voigtländer 

http://wwwtcs.inf.tu-dresden.de/~voigt/HOSC.pdf 

will probably kill you, so don't. But The Web is full of articles. You can
even read one or two of my own productions. 

I - sorry for shameless auto-ad - cited this paper *twice*, once it was
after *your* similar statement... 

http://users.info.unicaen.fr/~karczma/arpap/lazypi.pdf 

It is called "The Most Unreliable Technique in the World to Compute PI",
and it has been written explicitly for fun and instruction. That's
a possible answer to your dilemma. 

Another one shows something even worse than borrowing from the future,
namely "going backwards in time", applied to the Automatic Differentiation
in Reverse Mode. 

http://users.info.unicaen.fr/~karczma/arpap/revpearl.pdf 

And, please, avoid saying that something is scary or difficult, unless
you are really sure. 

Jerzy Karczmarczuk