-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 cornmouse wrote:
I have a txt file, which contains a paragraph. I am trying to read the file, and pass the contents of the file as a string to another function called "createIndex". "createIndex" is a function to generate index of the input string.
Below is my code to read the file :
main :: IO () main = do putStr "Enter input file name.txt: " filename <- getLine content <- readFile filename createIndex content
createIndex :: String -> [ ([Int], String) ] createIndex {- contents of the function... -}
I am using Hugs compiler, when i execute, i got an error Type error in generator *** Term : showString content *** Type : [Char] -> [Char] *** Does not match : IO a
IO>
I know the data type doesn't match. How do i go about this?
If you're going to be doing something more with the value later in the 'do' block, you can use 'let' in the do block (since createIndex doesn't (have to) do any IO -- there is no IO in its type -- it doesn't have to be run as an IO action (in fact it can't be, which is why there is an error message)) : do putStr "Enter input file name.txt: " filename <- getLine content <- readFile filename let contentIndex = createIndex content ... ... probably use contentIndex somewhere ... ... Isaac -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFF7qFkHgcxvIWYTTURApwoAKDIn0TcRgD+TRePt0FSxvNph+cyqgCeKhQd yEvF/zEO+eYDivMivXhOmOE= =mcFN -----END PGP SIGNATURE-----