[Haskell-cafe] Input/Output file

Sara Kenedy sarakenedy at gmail.com
Mon Jul 3 10:43:53 EDT 2006

Hi all,

I have a module Test.hs:

module Test where
import IO
readMsgFile = do
        putStr "Input file: "
        ifile <- getLine
        putStr "Output file: "
        ofile <- getLine
        s <- readFile ifile
        writeFile ofile (test s)

--test function
test :: String -> String
test s
	|s == "true"  = "True"
	|s == "false" = "False"
	|otherwise = []

Then, I run
*Test> readMsgFile
Input file: test1.txt
Output file: result1.txt

The content of test1.txt is string "true". So I expect the result in
"result1.txt" is "True"
But, open file "result1.txt", it displays empty.

I do not know why it does not return correct answer. If you don't
mind, please share with me. Thanks a lot.


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