This module provides a replacement for the normal (unicode unaware) IO functions of haskell. By using implicit parameters, it can be used almost as a drop-in replacement. For example, consider the following simple echo program:

 main = do
   str <- getContents
   putStr str

To make this program process UTF-8 data, change the program to:

 

 import Prelude hiding (getContents,putStr)
 import System.IO.Encoding
 import Data.Encoding.UTF8

 main = do
   let ?enc = UTF8
   str <- getContents
   putStr str

Or, if you want to use the standard system encoding:

 

 import Prelude hiding (getContents,putStr)
 import System.IO.Encoding

 main = do
   e <- getSystemEncoding
   let ?enc = e
   str <- getContents
   putStr str