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Parse Error In Pattern Putstr

then ... y What is x when b is false? palin :: IO () palin = do line <- getLine putStr line --Probably better to use putStrLn? Move 'b' to 'c'. have a peek here

It cons-tructs a list by providing the "head" element on the left, and a "tail" list on the right ghci> 1 : [2,3,4] [1,2,3,4] You can pattern match on lists with I'm going to attach an actual write up done on another forum, it wasn't by me and I forgot the persons name but he/she explained it pretty well.Anyway these all give Register with Facebook Register with Twitter Android Cheats More Codecall → General Forums → General Programming Javascript Disabled Detected You currently have javascript disabled. Check out our Community Blogs Recent Topics Google Map does not load in Magento store locator page.

It wouldn't be hard to change it to do what you're trying to do with printList though. Even conditional statement is expression as well as putStr "hi" and they have their (return) values. Are there any circumstances when the article 'a' is used before the word 'answer'?

It states that if b is true then x = y otherwise x = z. Should run fine. –m09 May 2 '12 at 14:33 1 @JamieB That looks correctly indented. Haskell parse error on input 'if'? - Stack Overflow View More at http://stackoverflow.com/questions/23463132/haskell-parse-error-o... Here are some mistakes that have been observed from multiple sources. 1.1 Indentation Perhaps the first trip-up - you might understand that indentation defines where a code block starts and the

Join them; it only takes a minute: Sign up Haskell: Parse error in an IO program up vote 2 down vote favorite 1 I am writing a program to help my View More Recalll - Medium for programmers. Russell.) 1.7 Parentheses (The following tip on parentheses was contributed by the user 7stud in the thread "Top beginner mistakes" (see http://article.gmane.org/gmane.comp.lang.haskell.beginners/1121) on the Haskell-Beginners mailing list on Wed, 4 Mar It looks nice on paper, but is terrible for actually working with.

randInt :: Integer -> Integer randInt = unsafePerformIO . if True then putStr line else putStr "hi" --Also consider putStrLn here? else > statement. Back to top Back to General Programming · Next Unread Topic → Also tagged with one or more of these keywords: compile, haskell Language Forums → C and C++ → C++

Move 2 to 3. http://mail.haskell.org/pipermail/beginners/2010-February/003660.html uniqueideaman - Oct 12 2016 01:53 PM HostForLIFE.eu – Cheap Windows & ASP.NET Core 1.0.1 hosting | UNLIMITED Diskspace EUWindowsHost - Oct 09 2016 07:54 PM Square root estimation program rounding Interviewee offered code samples from current employer -- should I accept? Basically, if the list is empty, then stop.

If he binds the name sacFile1 to a value, there must come more > statements after it, so the "do" is required. > > But it might also be wrong indentation, navigate here One has 1 argument, the other has 2. It might help a little bit if you better explained what you are trying to do, or what you expect to be happening with the code you wrote. Haskell has no randInt function that works in the way you expect.

What is the possible impact of dirtyc0w a.k.a. "dirty cow" bug? I've seen other code that uses this syntax before, that's why I'm using all the parentheses. Select Only Printed Out Cells What kind of bugs do "goto" statements lead to? Check This Out Back to top #3 EGD Eric EGD Eric CC Newcomer Member 12 posts Posted 22 January 2012 - 06:30 PM Thanks for that, that was really helpfull.

How to do \widthof with a symbol Reduce function is not showing all the roots of a transcendental equation How to prove that a paper published with a particular English transliteration Why isn't tungsten used in supersonic aircraft? The code you posted has tabs in the following places (marked with --->) mathExercise times (a,b) = if times<=0 --->then return () --->else do let x = randInt a ---> let

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The code: mathExercise times (a,b) = if times<=0 then return () else do let x = randInt a let y = randInt b putStr (show x ++ " + "++ show Output the Hebrew alphabet more hot questions question feed lang-hs about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life / Username Forum Password I've forgotten my password Remember me This is not recommended for shared computers Privacy Policy beta Home Login Loading... Back to top #5 Sysop_fb Sysop_fb CC Addict Advanced Member 151 posts Location:Missouri Posted 23 January 2012 - 06:54 AM On your printlist functionIf you want to define a variable in

Join them; it only takes a minute: Sign up Haskell Formatting Issue up vote 1 down vote favorite 1 main :: IO () main = do contents <- readFile "text.txt" let Absolute value of polynomial Why did they bring C3PO to Jabba's palace and other dangerous missions? show . http://back2cloud.com/parse-error/parse-error-parse-error-unexpected-t-static-expecting-t-old-function.php randomInt –scholar guy Jul 17 at 12:55 add a comment| Your Answer draft saved draft discarded Sign up or log in Sign up using Google Sign up using Facebook Sign

This was the primary problem, though. how can that be done using sequence? –Rog Matthews Jan 16 '12 at 6:20 2 I think you're best off asking something unrelated like that as a separate question. –Tikhon Also the parse error on the if statement is because there shouldn't actually be an if statement where you are trying to put one, you have already completed the definition of main = do putStr "List: " printList ls let revls = reverse ls putStr "List: " printList revls putStrLn ( "last element: " ++ show (last revls)) putStrLn ( "2nd element:"

Here, the error message doesn't help to recognize the problem. (Entry added by Benjamin L. Haskell uses indentation as a cue to parse sections of code. Jamais. Why is the old Universal logo used for a 2009 movie?

This separates the head of the list (a, b) from the tail of the list moves, which then is further matched against ((a, b):moves) on the next recursive call. Move 1 to 3. asked 1 year ago viewed 310 times active 1 year ago Visit Chat Related 0Parse error in Haskell11Haskell: Parse error in pattern1Haskell - Parse error in pattern0Haskell - Parse error on Recent content is available under a simple permissive license.

I really did not notice this when I write it. The problem is how to iterate over the elements (pairs) of the list while separating the first a of each pair from the second a. One example that recently (in April, 2008) appeared on the Haskell-Cafe mailing list (see the reply post Re: Embedding newlines into a string?) was the following. One should also recognize that the types returned by the then and else branches must match due to Haskell's strong and static type system.

Is it illegal to DDoS a phishing page? Yes, that is the problem. Anything appearing after it will take precedence over anything that comes before.For example, lets say you've got a line that reads:putStrLn (show (1 + 1))If you want to get rid of