haskell word searching program development - function

Question

hello I am making some word searching program
for example
when "text.txt" file contains "foo foos foor fo.. foo fool"
and search "foo"
then only number 2 printed
and search again and again
but I am haskell beginner
my code is here
:module +Text.Regex.Posix
putStrLn "type text file"
filepath <- getLine
data <- readFile filepath
--1. this makes <interactive>:1:1: parse error on input `data' how to fix it?
parsedData =~ "[^- \".,\n]+" :: [[String]]
--2. I want to make function and call it again and again
searchingFunc = do putStrLn "search for ..."
search <- getLine
result <- map (\each -> if each == search then count = count + 1) data
putStrLn result
searchingFunc
}
sorry for very very poor code
my development environment is Windows XP SP3 WinGhci 1.0.2
I started the haskell several hours ago sorry
thank you very much for reading!
edit: here's original scheme code
thanks!
#lang scheme/gui
(define count 0)
(define (search str)
(set! count 0)
(map (λ (each) (when (equal? str each) (set! count (+ count 1)))) data)
(send msg set-label (format "~a Found" count)))
(define path (get-file))
(define port (open-input-file path))
(define data '())
(define (loop [line (read-line port)])
(when (not (eof-object? line))
(set! data (append data
(regexp-match* #rx"[^- \".,\n]+" line)))
(loop)))
(loop)
(define (cb-txt t e) (search (send t get-value)))
(define f (new frame% (label "text search") (min-width 300)))
(define txt (new text-field% (label "type here to search") (parent f) (callback (λ (t e) (cb-txt t e)))))
(define msg (new message% (label "0Found ") (parent f)))
(send f show #t)

Answer 1

I should start by iterating what everyone would (and should) say: Start with a book like Real World Haskell! That said, I'll post a quick walkthrough of code that compiles, and hopefully does something close to what you originally intended. Comments are inline, and hopefully should illustrate some of the shortcomings of your approach.
import Text.Regex.Posix
-- Let's start by wrapping your first attempt into a 'Monadic Action'
-- IO is a monad, and hence we can sequence 'actions' (read as: functions)
-- together using do-notation.
attemptOne :: IO [[String]]
-- ^ type declaration of the function 'attemptOne'
-- read as: function returning value having type 'IO [[String]]'
attemptOne = do
putStrLn "type text file"
filePath <- getLine
fileData <- readFile filePath
putStrLn fileData
let parsed = fileData =~ "[^- \".,\n]+" :: [[String]]
-- ^ this form of let syntax allows us to declare that
-- 'wherever there is a use of the left-hand-side, we can
-- substitute it for the right-hand-side and get equivalent
-- results.
putStrLn ("The data after running the regex: " ++ concatMap concat parsed)
return parsed
-- ^ return is a monadic action that 'lifts' a value
-- into the encapsulating monad (in this case, the 'IO' Monad).
-- Here we show that given a search term (a String), and a body of text to
-- search in, we can return the frequency of occurrence of the term within the
-- text.
searchingFunc :: String -> [String] -> Int
searchingFunc term
= length . filter predicate
where
predicate = (==)term
-- ^ we use function composition (.) to create a new function from two
-- existing ones:
-- filter (drop any elements of a list that don't satisfy
-- our predicate)
-- length: return the size of the list
-- Here we build a wrapper-function that allows us to run our 'pure'
-- searchingFunc on an input of the form returned by 'attemptOne'.
runSearchingFunc :: String -> [[String]] -> [Int]
runSearchingFunc term parsedData
= map (searchingFunc term) parsedData
-- Here's an example of piecing everything together with IO actions
main :: IO ()
main = do
results <- attemptOne
-- ^ run our attemptOne function (representing IO actions)
-- and save the result
let searchResults = runSearchingFunc "foo" results
-- ^ us a 'let' binding to state that searchResults is
-- equivalent to running 'runSearchingFunc'
print searchResults
-- ^ run the IO action that prints searchResults
print (runSearchingFunc "foo" results)
-- ^ run the IO action that prints the 'definition'
-- of 'searchResults'; i.e. the above two IO actions
-- are equivalent.
return ()
-- as before, lift a value into the encapsulating Monad;
-- this time, we're lifting a value corresponding to 'null/void'.
To load this code, save it into a .hs file (I saved it into 'temp.hs'), and run the following from ghci. Note: the file 'f' contains a few input words:
*Main Text.Regex.Posix> :l temp.hs
[1 of 1] Compiling Main ( temp.hs, interpreted )
Ok, modules loaded: Main.
*Main Text.Regex.Posix> main
type text file
f
foo foos foor fo foo foo
The data after running the regex: foofoosfoorfofoofoo
[1,0,0,0,1,1]
[1,0,0,0,1,1]
There is a lot going on here, from do notation to Monadic actions, 'let' bindings to the distinction between pure and impure functions/values. I can't stress the value of learning the fundamentals from a good book!

Answer 2

Here is what I made of it. It doesn't does any error checking and is as basic as possible.
import Text.Regex.Posix ((=~))
import Control.Monad (when)
import Text.Printf (printf)
-- Calculates the number of matching words
matchWord :: String -> String -> Int
matchWord file word = length . filter (== word) . concat $ file =~ "[^- \".,\n]+"
getInputFile :: IO String
getInputFile = do putStrLn "Enter the file to search through:"
path <- getLine
readFile path -- Attention! No error checking here
repl :: String -> IO ()
repl file = do putStrLn "Enter word to search for (empty for exit):"
word <- getLine
when (word /= "") $
do print $ matchWord file word
repl file
main :: IO ()
main = do file <- getInputFile
repl file

Answer 3

Please start step by step. IO in Haskell is hard, so you shouldn't start with file manipulation. I would suggest to write a function that works properly on a given String. That way you can learn about syntax, pattern matching, list manipulation (maps, folds) and recursion without beeing distracted by the do notation (which kinda looks imperative, but isn't, and really needs a deeper understanding).
You should check out Learn you a Haskell or Real World Haskell to get a sound foundation. What you do now is just stumbling in the dark - which may work if you learn languages that are similar to the ones you know, but definitely not for Haskell.