Haskell: hIsEOF: Check end of file

hIsEOF takes a readable file handle and return IO True, if no further input can be taken from hdl or for a physical file (or) IO False.

Prelude System.IO> :t hIsEOF

hIsEOF :: Handle -> IO Bool

FileUtil.hs

import System.IO

readDataFrom fileHandle = 
    do 
        isFileEnd <- hIsEOF fileHandle
        if isFileEnd 
            then
                return ("")
            else
                do
                    info <- hGetLine  fileHandle
                    putStrLn info
                    readDataFrom fileHandle


main = 
    do
        putStrLn "Enter file name (Including full path) to read"
        fileName <- getLine
        fileHandle <- openFile fileName ReadMode

        readDataFrom fileHandle

$ runghc FileUtil.hs
Enter file name (Including full path) to read
today.txt
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
11, 12, 13, 14, 15, 16, 17, 18, 19, 20
21, 22, 23, 24, 25, 26, 27, 28, 29, 30
31, 32, 33, 34, 35, 36, 37, 38, 39 40

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