[Haskell-beginners] A first try

David Place d at vidplace.com
Fri Jun 24 14:43:59 CEST 2011

Hi, Panagiotis.

The wc program is a good choice for a learning program, but it reveals a long-standing weakness in Haskell: Lazy-IO.  I think you will find that your program will get an error if you try to run wc on many files.  You will open too many files at once.  

There is a solution called IterateeIO.  It's extremely elegant and very good Haskell, but quite challenging to understand.  So far, I have not found a good tutorial.

Luck for you the best example program is an implementation of wc!

I posted it in hpaste.org.  (A Haskell-specific version of pasteBin.)

> http://hpaste.org/48254


David Place   
Owner, Panpipes Ho! LLC
d at vidplace.com

On Jun 24, 2011, at 7:48 AM, Panagiotis Koutsourakis wrote:

> Hello all,
> I've been spending some time recently learning Haskell. I am not a
> newbie in programming, and I've had some experience with lisp in the
> past, but I have not really studied functional programming. I am
> mostly seeking feedback regarding style, and glaring mistakes that I
> may make in some toy examples, but I am not sure if this is the proper
> place to ask.
> In case it is though, here is an attempt (not yet complete) at the
> word count program:
> http://pastebin.com/JZw22QGA
> Thanks in advance!
> -- 
> Panagiotis Koutsourakis
> _______________________________________________
> Beginners mailing list
> Beginners at haskell.org
> http://www.haskell.org/mailman/listinfo/beginners

More information about the Beginners mailing list