[Haskell-cafe] Unicode vs. System.Directory

[Arie Peterson]

After upgrading to haskell-platform-2010.1.0.0, with the improved unicode
support for IO in ghc-6.12, I hoped to be able to deal with filenames
containing non-ascii characters. This still seems problematic, though:

$ ls
m×n♯α
$ ghci
GHCi, version 6.12.1: http://www.haskell.org/ghc/  :? for help
Prelude> :m +System.Directory 
Prelude System.Directory> getDirectoryContents "." >>= mapM_ putStrLn
..
mÃnâ¯Î±
.

I hope this passes through the various email systems unharmed; on my
terminal, the output of 'ls' contains shiny unicode characters, while
'ghci' garbles up the filename. (My locale is en_GB.utf8.)

Similar problems arise with functions such as 'copyFile', which refuses to
handle filenames with non-ascii characters (unless wrapping it with
encoding functions).


Is this a known problem? I searched ghc's trac, but there are no relevant
bugs for the component 'libraries/directory'.


I have parts of a unicode-aware layer on top of System.Directory laying
around somewhere. I was rather hoping to ditch it, but I can polish it and
put it on hackage, if people are interested.


Kind regards,

Arie