File: openFile004.hs

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-- !!! Open a non-existent file for writing

import Control.Monad
import Data.Char
import System.Directory
import System.IO

file = "openFile004.out"

main = do
  b <- doesFileExist file
  when b (removeFile file)

  h <- openFile file WriteMode
  hPutStr h "hello world\n"
  hClose h

  h <- openFile file ReadMode
  let loop = do
        b <- hIsEOF h
        if b then return ()
             else do c <- hGetChar h; putChar c; loop
  loop