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Parse Error In Pattern Putstr

Not the answer you're looking for? It states that if b is true then x = y otherwise x = z. Connect to Services Connect to personal services for more relevant search results across services. Recent content is available under a simple permissive license. Source

Basically, if the list is empty, then stop. Couldn't match expected type `IO a0' with actual type `Bool' In a stmt of a 'do' expression: ls <= reverse ls In the expression: do { putStr "List: "; printList ls; Haskell, parse error in input 'if' - Stack Overflow View More at http://stackoverflow.com/questions/11814525/haskell-parse-error-i... show .

Cannot use hat in self-made command "Have permission" vs "have a permission" sort command : -g versus -n flag Would there be no time in a universe with only light? let x = if b then y -- compare to x = b? Select Only Printed Out Cells What kind of bugs do "goto" statements lead to? 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

I would appreciate it. show) (1 + 1)If that's too many parenthesis for your liking, get rid of them with the '$' operator:putStrLn . If you're using a text editor that can display literal tabs in a special way, set it up to do so; it will save you some headaches. y What is x when b is false?

Haskell: parse error on input 'putStrLn' - Stack Overflow View More at http://stackoverflow.com/questions/16880078/haskell-parse-error-o... If you're using Tabs, change them to whitespaces. computeKnapsack (sort fracList) computeKnapsack $ sort fracList computeKnapsack sort(fracList) computeKnapsack sort (fracList) computeKnapsack sort fracList sort fracList Haskell, parse error in input 'if' - Stack Overflow View More at http://stackoverflow.com/questions/11814525/haskell-parse-error-i... What is the possible impact of dirtyc0w a.k.a. "dirty cow" bug?

Main> putStr (hanoi_shower (hanoi 1 2 3 2)) Move 1 to 2. show $ 1 + 1Also this will work since you can turn + 1 into a functionputStrLn . Rather than using if length (x:xs) <= 1 howMany :: [a] -> String howMany [] = "Zero" howMany [x] = "One" howMany (x:xs) = "Many" Haskell functions can be defined with Tried it with just '.' or just ++, but that didn't work.

Hide Comments · Unlock · Lock 02 Jan JackJames hi i am jack i am seo expert jack james would love you to read new post Hide Comments View All Updates I've looked for examples, but oddly enough, I can't seem to find any where the functions are multilined. Browse other questions tagged haskell parse-error or ask your own question. You can apply this behaviour only to .hs files quite easily if I'm not mistaken. –m09 May 2 '12 at 14:35 | show 5 more comments up vote 0 down vote

How to improve this plot? this contact form Extreme Value Theorem on Manifold Problem to left align within a split Movie about a board-game that asks the players touchy questions "Have permission" vs "have a permission" apt-get how to 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++ Haskell doesn't let you do stuff like that which other languages might let you get away with.So to concatenate the strings you'd need to turn it into a string an easy

asked 4 years ago viewed 2080 times active 7 months ago Visit Chat Related 761Getting started with Haskell309What is Haskell actually useful for?13Tracking down errors in Haskell88Haskell error parse error on Here is the result of executing the above code in WinHugs: Main> putStr (hanoi_shower (hanoi 'a' 'b' 'c' 2)) Move 'a' to 'b'. Jamais. have a peek here randInt :: Integer -> Integer randInt = unsafePerformIO .

ghci> let (x:xs) = [1,2,3,4] ghci> x 1 ghci> xs [2,3,4] The way that you are using (x:xs) in your code hints that you do not yet have a firm grasp Why do you need IPv6 Neighbor Solicitation to get the MAC address? 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.

Is this alternate history plausible? (Hard Sci-Fi, Realistic History) DM adds overly powerful homebrew items to published adventures Why isn't tungsten used in supersonic aircraft?

GHC 7.0.1 and later). 1.2 If / Then / Else if-then statements must always include an 'else' portion. Haskell has pattern matching that lets you iterate through a list pretty easily.The code below uses pattern matching to break down a list into a cons format. What some miss is that then and else, if used within a section of code where indentation matters, must be indented deeper than the if statement. else > statement.

how much interest did Sauron have in Erebor? if True then putStr line else putStr "hi" --Also consider putStrLn here? Are there any circumstances when the article 'a' is used before the word 'answer'? Check This Out asked 4 years ago viewed 434 times active 4 years ago Visit Chat Linked 1 How Can I Make a Simple Exit in Haskell?

You probably meant to name the second fractionalKnapsack'. Another common mistake that some beginners make is writing "if" in front of the guard conditions; viz.: myfunction x y | if x < 2 = "a" | if y > In Haskell, an if-else expression does not mean "if true, execute foo; else, execute bar", but "if true, the value is foo; else, the value is bar". The problematic code segment was the following: hanoi_shower :: Show a => [(a, a)] -> String hanoi_shower [(a, b)] = "Move " ++ show a ++ " to " ++ show

Here, one coder attempted to write a function hanoi to solve the Towers of Hanoi problem, but to code it so that each tower could be named polymorphically, using, for example, Haskell has no randInt function that works in the way you expect. The else, the baz and the zap are all indented further than the if, so they all belong to the if-expression (as intended). main :: IO () main = do argList <- getArgs case argList of [] -> putStrLn "No filename ..." (f:_) -> realWork f or if null argList then putStrLn "..." else

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 Several functions may not work. But you never know with tabs, don't use tabs in Haskell code, configure your editor to indent with spaces. –Daniel Fischer May 2 '12 at 14:35 2 BTW I suggest There are other ways of iterating over lists as well.

Move 'a' to 'c'. 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 Why is the old Universal logo used for a 2009 movie? share|improve this answer edited Apr 8 '15 at 17:28 answered Apr 8 '15 at 17:12 Cirdec 18.1k12767 2 I added one possible implementation using randomIO I hope you don't mind

Passing different value (link value) from VF page to VF component and display it on screen Words that are both anagrams and synonyms of each other Digital Alarm Clock A word Started by AnkitRana, 19 Oct 2013 haskell 2 replies 705 views AnkitRana 19 Oct 2013 Language Forums → C and C++ → How to compile this old source code randomInt` –scholar guy Jul 17 at 12:53 | show 1 more comment 2 Answers 2 active oldest votes up vote 8 down vote You have mixed tabs and spaces. case option of "1" -> putStrLn(formatDatabase newDb) "2" -> do putStr "Name of film: " title <- getLine putStr "Name of director: " director <- getLine putStr "Year of release: "

But since there's no "do" after the "else", all that is on one logical line, it's parsed as ... = do xxx if blah then do { foo; bar } else Haskell, parse error in input 'if' - Stack Overflow View More at http://stackoverflow.com/questions/11814525/haskell-parse-error-i...