UTF-8
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(Difference between revisions)
(whoops, reuse the same example, why don't we) |
(question - what about other string encodings?) |
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provides a drop-in replacement for System.IO | provides a drop-in replacement for System.IO | ||
| - | + | ''What about other string encodings?'' | |
| - | + | == Example == | |
| - | + | If we use a function from System.IO.UTF8, we should also hide the equivalent one from the Prelude. (Alternatively, we could import the UTF8 module qualified) | |
| - | If we use a function from | + | |
<haskell> | <haskell> | ||
> import System.IO.UTF8 | > import System.IO.UTF8 | ||
| - | > import Prelude hiding (readFile) | + | > import Prelude hiding (readFile, writeFile) |
| + | > import System.Environment (getArgs) | ||
</haskell> | </haskell> | ||
| + | |||
| + | The readFile and writeFile functions are the same as before... | ||
<haskell> | <haskell> | ||
| Line 20: | Line 22: | ||
> do args <- getArgs | > do args <- getArgs | ||
> mapM_ reverseUTF8File args | > mapM_ reverseUTF8File args | ||
| - | + | ||
> reverseUTF8File :: FilePath -> IO () | > reverseUTF8File :: FilePath -> IO () | ||
> reverseUTF8File f = | > reverseUTF8File f = | ||
| - | > do | + | > do c <- readFile f |
| - | > writeFile (f ++ ".rev) $ reverseLines | + | > writeFile (f ++ ".rev") $ reverseLines c |
> where | > where | ||
> reverseLines = unlines . map reverse . lines | > reverseLines = unlines . map reverse . lines | ||
| - | + | </haskell> | |
Current revision
The simplest solution seems to be to use the utf8-string package from Galois. It
provides a drop-in replacement for System.IO
What about other string encodings?
Example
If we use a function from System.IO.UTF8, we should also hide the equivalent one from the Prelude. (Alternatively, we could import the UTF8 module qualified)
> import System.IO.UTF8 > import Prelude hiding (readFile, writeFile) > import System.Environment (getArgs)
The readFile and writeFile functions are the same as before...
> main :: IO () > main = > do args <- getArgs > mapM_ reverseUTF8File args > reverseUTF8File :: FilePath -> IO () > reverseUTF8File f = > do c <- readFile f > writeFile (f ++ ".rev") $ reverseLines c > where > reverseLines = unlines . map reverse . lines
