[Haskell-beginners] Does System.Directory work on Windows XP?

Daniel Fischer daniel.is.fischer at web.de
Wed Nov 4 19:59:12 EST 2009

Am Donnerstag 05 November 2009 01:14:59 schrieb Patrick Larrivee-Woods:
> With 6.10.4 it works fine. Thanks for your help,  I hadn't even realized
> I was using an older version.
> Cheers,
> Patrick

Just to explain:

getDirectoryContents "." is an IO action producing a String.
In newer GHC releases (I don't remember whther that change came with 6.6 or 6.8), when you 
invoke an IO action from the ghci-prompt, if the value returned from the action has not 
type (), by default it is bound to the variable 'it' and printed out (since it's not 
unconditionally a good thing to do that - consider readFile "HUGEFile.txt" - it can be 
disabled via
ghci> :set -fno-print-bind-result
- re-enable with -fprint-bind-result).
Before, the action was simply run and its result not printed out, to use the result of an 
IO action, you had to use
ghci> res <- getDirectoryContents "."
ghci> print res

ghci> getDirectoryContents "." >>= mapM_ putStrLn
or whatever.

If you still have 6.4.2 installed, you can try it out (but do your real work with the 
newer, it produces better code).

> Jason Dusek wrote:
> >   Could you try a recent version of GHC and let us know if you
> >   still have trouble?
> >
> > --
> > Jason Dusek

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