Prelude.writeFile with a Chinese file name

Question

I'm testing something that like to output content to file, which has a Chinese name.

The file would be created successfully with right content but not file name.

I take a look at the function writeFile^1 and it represents file name using String. So I suspect this might be root cause.

    file :: FilePath
    file = "上海万达影城.html"

    content :: String
    content = "<h1>hello</h1>"

    write2File :: IO ()
    write2File = writeFile file content

Thanks your help!

-Simon

--------------------- Updated

1. GHC at my side is 7.0.2

2. A workaround found before upgrade. see detail below and the code change like

   import qualified Codec.Binary.UTF8.String as UTF8
   file = UTF8.encodeString "上海万达影城.html"
   

Answer 1

String is a list of unicode code points in Haskell. The interpretation of that list of unicode code points is system dependent. (You also need a not too old GHC to support this).

Generally though, once you're locale is set correctly, things just work.

---

N.B. there have been caveats in the past -- e.g. the old bug: System.Directory.getDirectoryContents unicode support - which might involve workarounds.

Answer 2

In the meantime, you can use the System.Posix.IO.ByteString module. This will let you specify file paths as byte strings, so you can do the encoding/decoding yourself.

This is a known bug, and was fixed in 7.2.1.

http://hackage.haskell.org/trac/ghc/ticket/3307