使haskell程序在（大致）恒定内存中运行

我正在尝试接收CSV文件，对其进行错误检查，然后打印错误消息

mapM（appendFile filePath）（返回[string]的errorCheck函数）

这是可行的，但当我在很长的CSV上运行它时，它会耗尽内存。 我认为问题在于它太懒了，在做任何事情之前，它会将整个CSV加载到内存中。我已经尝试过使用BangPatterns增强严格性，但我不确定我是否正确使用了它，因为它没有帮助

我可以提供更多信息或代码，但我不确定什么与我的问题相关

代码：

main=do
safeRead s=catch（readFile s）$\\返回“”
文件路径x）（解析CSV文件）））错误（MSGS）））
--以正确的号码退出
存在。退出失败。exitCtrl$（errorCheckFile（（\（右x）->x）（parseCSV文件））（errorCheckCols（checkCols$head$（\（右x）->x）（parseCSV文件））errorMsgs））
--决定退出时使用的值，这取决于是错误、警告还是无
exitCtrl:：[String]->Int
exitCtrl[]=1
exitCtrl（行：rest）
|（“错误：”）==取6行=3
--|元素（“警告：”）行=1
|否则=exitCtrl rest
--获取给定文件路径的文件名
getFileName:：String->String
getFileName文件路径=反向$takeWhile（/='\\'）（反向文件路径）
--更改输入文件路径以在同一位置创建新的错误文件
createErrorFilePath:：String->String
createErrorFilePath路径输入=（反向$drop 4（反向路径输入））++“\u error\u log.txt”
--检查是否有任何列出错
errorCheckCols:：[Int]->[String]->String
errorCheckCols cols错误
|errorPos==Nothing=“所有标题均已说明：）”
|否则=错误！！（fromJust errorPos）
其中errorPos=findIndex（=1-2）列
--这会获取该文件，如果其中任何列不存在，则会告诉您，否则会错误检查数据库
errorCheckFile:：[[String]]->String->[String]
errorCheckFile[].[“错误：无数据”]
errorCheckFile（标题：[]）colErrorMsg=[“错误：无数据”]
errorCheckFile（标题：info）colErrorMsg
|长度标题>25=[“错误：数据列太多”]
|colErrorMsg==“所有标题均已入账：）”=
checkDB
信息
（findCol“示例名称1”标题3）
（findCol“示例名称2”标题5）
（findCol“示例名称3”标题5）
（findCol“示例名称4”标题3）
（findCol“示例名称5”标题3）
（findCol“示例名称6”标题3）
（findCol“示例名称7”标题8）
（findCol“示例名称8”标题3）
（findCol“示例名称9”标题15）
（findCol“示例名称10”标题15）
（findCol“示例名称11”标题3）
（findCol“示例名称12”标题3）
（findCol“示例名称13”标题9）
（findCol“示例名称14”标题16）
（findCol“示例名称15”标题9）
（findCol“示例名称16”标题16）
（findCol“示例名称17”标题3）
（findCol“示例名称18”标题3）
（findCol“示例名称19”标题8）
（findCol“示例名称20”标题3）
（（findCol“示例名称21”标题20）+（findCol“示例名称21替换”标题20）+1）
（findCol“示例名称22”标题22）
（findCol“示例名称23”标题3）
（findCol“示例名称24”标题3）
（findCol“示例名称25”标题9）
1.
|否则=[colErrorMsg]
--给定输入标题，按名称查找每行的位置
checkCols:：[String]->[Int]
checkCols标题=[（findCol“示例名称1”标题3），
（findCol“示例名称2”标题5），
（findCol“示例名称3”标题5），
（findCol“示例名称4”标题3），
（findCol“示例名称5”标题3），
（findCol“示例名称6”标题3），
（findCol“示例名称7”标题8），
（findCol“示例名称8”标题3），
（findCol“示例名称9”标题15），
（findCol“示例名称10”标题15），
（findCol“示例名称11”标题3），
（findCol“示例名称12”标题3），
（findCol“示例名称13”标题9），
（findCol“示例名称14”标题16），
（findCol“示例名称15”标题9），
（findCol“示例名称16”标题16），
（findCol“示例名称17”标题3），
（findCol“示例名称18”标题3），
（findCol“示例名称19”标题8），
（findCol“示例名称20”标题3），
（（findCol“示例名称21”标题20）+（findCol“示例名称21替换”标题20）+1），
（findCol“示例名称22”标题22），
（findCol“示例名称23”标题3），
（findCol“示例名称24”标题3），
（findCol“示例名称25”标题9）]
--[[String]]Intx25 Int（count）返回一个[String]
checkDB:：[[String]->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->Int->[String]
checkDB[].[].[]错误：给定的文件名不存在]
checkDB（最后一行：[]）pos1 pos2 pos3 pos4 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 pos24 pos25计数
|地图（图珀）（最后一行！！位置4）==
main = do
    safeRead s = catch (readFile s) $ \_ -> return ""

    filePath <- safeRead "in.txt"
    file <- safeRead filePath

    --save the errors
    writeFile (createErrorFilePath filePath) (getFileName $ filePath ++ "\n")
    let !addToErr = do appendFile (createErrorFilePath filePath) 

    mapM_ addToErr (map ('\n':) (errorCheckFile (( \(Right x) -> x )  (parseCSV file)) (errorCheckCols (checkCols . head $ (( \(Right x) -> x )  (parseCSV file))) errorMsgs)))
    --exit with correct number
    exitWith . ExitFailure . exitCtrl $ (errorCheckFile (( \(Right x) -> x )  (parseCSV file)) (errorCheckCols (checkCols $ head $ (( \(Right x) -> x )  (parseCSV file))) errorMsgs)) 

--decides what value to exit with, depends on if errors, warnings or nothing
exitCtrl :: [String] -> Int
exitCtrl [] = 1
exitCtrl (line:rest) 
    | ("ERROR:") == take 6 line = 3
--    | elem ("WARNING:") line = 1
    | otherwise = exitCtrl rest

--gets a files name given a filepath                
getFileName :: String -> String
getFileName filePath =  reverse $ takeWhile (/= '\\') (reverse filePath)

--changes the input filepath to create a new error file at the same location
createErrorFilePath :: String -> String
createErrorFilePath pathIn = (reverse $ drop 4 (reverse pathIn)) ++ "_error_log.txt"

--check if any of the columns errored
errorCheckCols :: [Int] -> [String] -> String
errorCheckCols cols errors 
    | errorPos == Nothing = "All headings are accounted for :)"
    | otherwise = errors !! (fromJust errorPos)
        where errorPos = findIndex (== 1-2) cols

--This takes the file and if any of the columns don't exists, tells you, otherwise it error checks the database    
errorCheckFile :: [[String]] -> String -> [String]
errorCheckFile [] _ = ["ERROR: No Data"]
errorCheckFile (headings:[]) colErrorMsg = ["ERROR: No Data"]
errorCheckFile (headings:info) colErrorMsg
    | length headings > 25 = ["ERROR: Too many Columns of data"]
    | colErrorMsg == "All headings are accounted for :)" = 
            checkDB 
                info 
                (findCol "example name 1" headings 3) 
                (findCol "example name 2" headings 5) 
                (findCol "example name 3" headings 5) 
                (findCol "example name 4" headings 3) 
                (findCol "example name 5" headings 3) 
                (findCol "example name 6" headings 3) 
                (findCol "example name 7" headings 8) 
                (findCol "example name 8" headings 3) 
                (findCol "example name 9" headings 15) 
                (findCol "example name 10" headings 15) 
                (findCol "example name 11" headings 3) 
                (findCol "example name 12" headings 3) 
                (findCol "example name 13" headings 9) 
                (findCol "example name 14" headings 16) 
                (findCol "example name 15" headings 9) 
                (findCol "example name 16" headings 16) 
                (findCol "example name 17" headings 3) 
                (findCol "example name 18" headings 3) 
                (findCol "example name 19" headings 8) 
                (findCol "example name 20" headings 3) 
                ((findCol "example name 21" headings 20) + (findCol "example name 21 alt" headings 20) + 1) 
                (findCol "example name 22" headings 22) 
                (findCol "example name 23" headings 3) 
                (findCol "example name 24" headings 3) 
                (findCol "example name 25" headings 9) 
                1
    | otherwise = [colErrorMsg]



--given the inputs headings, finds the positions if each row by name 
checkCols :: [String] -> [Int]
checkCols headings = [(findCol "example name 1" headings 3),
                (findCol "example name 2" headings 5), 
                (findCol "example name 3" headings 5), 
                (findCol "example name 4" headings 3), 
                (findCol "example name 5" headings 3), 
                (findCol "example name 6" headings 3), 
                (findCol "example name 7" headings 8), 
                (findCol "example name 8" headings 3),
                (findCol "example name 9" headings 15), 
                (findCol "example name 10" headings 15), 
                (findCol "example name 11" headings 3), 
                (findCol "example name 12" headings 3), 
                (findCol "example name 13" headings 9), 
                (findCol "example name 14" headings 16), 
                (findCol "example name 15" headings 9), 
                (findCol "example name 16" headings 16), 
                (findCol "example name 17" headings 3), 
                (findCol "example name 18" headings 3), 
                (findCol "example name 19" headings 8), 
                (findCol "example name 20" headings 3), 
                ((findCol "example name 21" headings 20) + (findCol "example name 21 alt" headings 20) + 1), 
                (findCol "example name 22" headings 22), 
                (findCol "example name 23" headings 3), 
                (findCol "example name 24" headings 3), 
                (findCol "example name 25" headings 9)]


-- [[String]] Intx25 Int(count) returns a [String]
checkDB :: [[String]] -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> [String]
checkDB [] _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ = ["ERROR: Filename given does not exist"]
checkDB (lastRow:[]) pos1 pos2 pos3 pos4 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 pos24 pos25 count
    | map (toUpper) (lastRow !! pos4) == "ASD" = checkASD lastRow pos1 pos2 pos3 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 count
    | map (toUpper) (lastRow !! pos4) == "QWE" || map (toUpper) (lastRow !! pos4) == "DPS" = checkQWE lastRow pos1 pos2 pos3  pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos18 pos19 pos24 pos25 pos17 count 
    | otherwise = ["ERROR: identifier not valid on line " ++ (show count)]
checkDB (firstRow:otherRows) pos1 pos2 pos3 pos4 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 pos24 pos25 count
--    | count `mod` 50 == 0 = []
    | map (toUpper) (firstRow !! pos4) == "ASD" = checkASD firstRow pos1 pos2 pos3 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 count ++ checkDB otherRows pos1 pos2 pos3 pos4 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 pos24 pos25 (count+1)
    | map (toUpper) (firstRow !! pos4) == "QWE" || map (toUpper) (firstRow !! pos4) == "DPS" = checkQWE firstRow pos1 pos2 pos3  pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos18 pos19 pos24 pos25 pos17 count ++ checkDB otherRows pos1 pos2 pos3 pos4 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 pos24 pos25 (count+1)
    | otherwise = ["ERROR: identifier not valid on line " ++ (show count)] ++ checkDB otherRows pos1 pos2 pos3 pos4 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 pos24 pos25 (count+1) 

--collection of error checking methods for ASD rows
checkASD :: [String] -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> [String]
checkASD row pos1 pos2 pos3 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos17 pos18 pos19 pos20 pos21 pos22 pos23 count
    | sum ans == 0 = []
    | (findIndex (>=20) ans /= Nothing && findIndex (>0) ans /= Nothing) = ["WARNING: At line " ++ (show count) ++ " at column(s) " ++ (show (cols!!(fromJust(findIndex (>=20) ans)) + 1))]
    | findIndex (>=20) ans /= Nothing = ["WARNING: At line " ++ (show count) ++ " at column(s) " ++ (show (cols!!(fromJust(findIndex (>=20) ans)) + 1)) ++ "\nERROR: At line " ++ (show count) ++ " at column(s) " ++ unwords( map show( map (+1) (map (cols!!) (findIndices (>0) (init ans)))))]
    | otherwise = ["ERROR: At line " ++ (show count) ++ " at column(s) " ++ unwords( map show( map (cols!!) (findIndices (>0) ans))) ]
    where 
         ans = [errorCheck (row!!pos1) ["01","02","03","04","05"],
                errorCheck (row!!pos2) ["3","4"],
                errorCheck (row!!pos3) ["1","2","3","4","5","6","7","8","9","10","11","12","13","14","15","16","17","18","19","20"],
                checkTypeLength (row!!pos5) isDigit 5,
                sum [ checkLength (row!!pos6) 12, errorCheckNL (row!!pos6) ],
                checkDate (row!!pos7),
                checkTypeLength (row!!pos8) checkSex 1,
                checkDate (row!!pos9),
                checkDate (row!!pos10),
                checkLength (row!!pos11) 5,
                checkTypeLength (row!!pos12) isDigit 5,
                checkMoney (row!!pos13),
                checkMoney (row!!pos14),
                checkMoney (row!!pos15),
                checkMoney (row!!pos16), 
                checkLength (row!!pos17) 10,
                checkLength (row!!pos18) 2,
                checkDate (row!!pos19), 
                checkTypeLength (row!!pos20) isDigit 5,
                checkTypeLength (row!!pos21) isDigit 5,
                checkLength (row!!pos22) 1,
                checkLength (row!!pos23) 1]
         cols = [pos1, pos2, pos3, pos5, pos6, pos7, pos8, pos9, pos10, pos11, pos12, pos13, pos14, pos15, pos16, pos17, pos18, pos19, pos20, pos21, pos22, pos23]
         --cols is a quick fix for finding where errors have occured

--collection of error checking methods for QWE/DPS rows
checkQWE :: [String] -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> [String]    
checkQWE row pos1 pos2 pos3 pos5 pos6 pos7 pos8 pos9 pos10 pos11 pos12 pos13 pos14 pos15 pos16 pos18 pos19 pos24 pos25 pos17 count
    | sum ans == 0 = []
    | (findIndex (>=20) ans /= Nothing && findIndex (>0) ans /= Nothing) = ["WARNING: At line " ++ (show count) ++ " at column(s) " ++ (show (cols!!(fromJust(findIndex (>=20) ans)) + 1))]
    | findIndex (>=20) ans /= Nothing = ["WARNING: At line " ++ (show count) ++ " at column(s) " ++ (show (cols!!(fromJust(findIndex (>=20) ans)) + 1)) ++ "\nERROR: At line " ++ (show count) ++ " at column(s) " ++ unwords( map show( map (+1) (map (cols!!) (findIndices (>0) (init ans)))))]
    | otherwise = ["ERROR: At line " ++ (show count) ++ " at column(s) " ++ unwords( map show (map (cols!!) (findIndices (>0) ans))) ]
    where
         ans = [errorCheck (row!!pos1) ["01","02","03","04","05","06","07","08","1","2","3","4","5","6","7","8"],
                errorCheck (row!!pos2) ["1","2","3","4"],
                errorCheck (row!!pos3) ["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"],
                checkTypeLength (row!!pos5) isDigit 5,
                sum [ checkLength (row!!pos6) 12, errorCheckNL (row!!pos6) ],
                checkDate (row!!pos7),
                checkTypeLength (row!!pos8) checkSex 1,
                checkDate (row!!pos9),
                checkDate (row!!pos10),
                checkLength (row!!pos11) 5,
                checkTypeLength (row!!pos12) isDigit 5,
                checkMoney (row!!pos13),
                checkMoney (row!!pos14),
                checkMoney (row!!pos15),
                checkMoney (row!!pos16),
                checkLength (row!!pos18) 2,
                checkDate (row!!pos19),
                checkDate (row!!pos24), 
                checkMoney (row!!pos25),
                checkQWEpos17 (row!!pos17)]
         cols = [pos1, pos2, pos3, pos5, pos6, pos7, pos8, pos9, pos10, pos11, pos12, pos13, pos14, pos15, pos16, pos18, pos19, pos24, pos25, pos17]
         --cols is a quick fix for finding where errors have occured


--checks that a string is 'm' or 'f'
checkSex :: Char -> Bool
checkSex input 
    | toLower input == 'm' || toLower input == 'f' = True
    | otherwise = False

--finds if a row has something other than 1 type and are of a certain length
checkTypeLength :: String -> (Char -> Bool) -> Int -> Int
checkTypeLength [] _ _ = 1
checkTypeLength el isType maxSize
    | length el > 0 && length el <= maxSize && (and $ map isType el) = 0
    | otherwise = 1

--finds elements that exceed a certain length
checkLength :: String -> Int -> Int
checkLength [] _ = 1
checkLength el maxSize
    | length el <= maxSize && length el > 0 = 0
    | otherwise = 1

--finds a columns position given its name and the list of column names, else returns -1
findCol :: String -> [String] -> Int -> Int
findCol colName header unique   --unique is the number of letters of each word that need to be compared
    | findMatch /= Nothing = fromJust findMatch
    | otherwise = -1
    where findMatch = findIndex (==(map (toLower) (take unique colName))) (map (map toLower) (map (take unique) header))

--finds if a line where the element is not a letter and number ONLY, returns col num or 0
errorCheckNL :: String -> Int
errorCheckNL [] = 1
errorCheckNL (el1:el2:el3:rest)
    | isDigit el1 && isDigit el2 && isDigit el3 && and(map isLetter rest) = 0 --return Nothing?
    | otherwise = 2
errorCheckNL others = 3

-- given a row, the column num to check, options of what the column and a counter==0, returns row num or 0
errorCheck :: String -> [String] -> Int
errorCheck [] _ = 1
errorCheck el options 
    | map toLower el `elem` options = 0
    | otherwise = 1

--finds if a date is valid given a row, the column num to check and a counter=0, returns row num or 0
checkDate :: String -> Int
checkDate [] = 1
checkDate el 
    | sepPos1 == Nothing = 1 --error: this is not formated as a date, there's no separator
    | sepPos2 == Nothing = 2 --error: this is not formated as a date, there's no separator
    | day `notElem` ["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"] = 3
    | (map toLower month) `notElem` ["jan","feb","mar","apr","may","jun","jul","aug","sep","oct","nov","dec"] = 4   --error: month is not valid
    | length (tail year) == 4 && and (map isDigit (tail year)) = 22
    | length (tail year) == 2 && and (map isDigit (tail year)) = 0
    | otherwise = 5
    where 
        sepPos1 = findIndex (== '-') el            --maybe
        (day, rest) = splitAt (fromJust sepPos1) el
        sepPos2 = findIndex (== '-') (tail rest)   --maybe
        (month, year) = splitAt (fromJust sepPos2) (tail rest)

--checks that quantities of money are presented correctly
checkMoney :: String -> Int
checkMoney [] = 4
checkMoney cash 
    | decimalPoint == Nothing && checkTypeLength cash isDigit 9 /= 0 = 1  --error: not numbers
    | decimalPoint /= Nothing && checkTypeLength (tail cents) isDigit 2 /= 0 = 2 --error: not numbers after the decimal point
    | decimalPoint /= Nothing && checkTypeLength euros isDigit 9 /= 0 = 3 --error: not numbers after the decimal point
    | otherwise = 0
    where
        decimalPoint = findIndex (== '.') cash     --maybe
        (euros, cents) = splitAt (fromJust decimalPoint) cash

(( \(Right x) -> x )  (parseCSV file))

logAndUpdate file exitCode record = do
    appendFile file (message record)
    return $! update exitCode (exitInfo record)

exitCode <- foldM (logAndUpdate filename) 0 (parsedRecords)
exitWith $ ExitCode exitCode