[Haskell-cafe] Unicode strings

Luis F. Araujo luis at arjox.org
Sun Nov 5 13:46:43 EST 2006

Pupeno wrote:
> Hello,
> I am trying to make a program that outputs some Unicode characters but the 
> output doesn't match what I try to print.
> Attached is a little test program. It tries to print the arrows "←↑→↓" but 
> instead it outputs "\220\221\222\223" (that is, character number 220, then 
> 221, then 222). I've also tried writing the Unicode code points (although GHC 
> 6.6 should deal just fine with Unicode source code) and I get the same 
> result. In case anybody wants to try, this would be the 
> string: "\8592\8593\8594\8595".
> I am also attaching the output file, you can see that the contents are not 
> right.
> Any ideas what am I doing wrong here ?
> Thank you.
> ------------------------------------------------------------------------
> import qualified System.IO as IO
> main = do
>     let str = "←↑→↓"
>     putStrLn str
>     h <- IO.openFile "test.output" IO.WriteMode 
>     IO.hPutStrLn h str
The problem is with the output of putStrLn. You need to encode the
string into utf8.

You can find several modules on the web, i have been using this one:


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