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Parse Error Possibly Incorrect Indentation Haskell

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Can an irreducible representation have a zero character? If it doesn't, you give a very precise error indicating exactly which bracket was not match. Can a nuclear detonation on Moon destroy life on Earth? squared :: Num a => a -> a or, if we only want Ints squared :: Int -> Int Now for mean mean :: Fractional a => [a] -> a We http://kiloubox.com/parse-error/parse-error-possibly-incorrect-indentation.html

doubleEveryOther' (x,y,xs) implies that the argument is a 3 element tuple. After that you can use the function like stddev [1..15] The function i provided is a very verbose step by step calculation. You can look at the code and try and figure out which pattern is missing, or you can compile the code with -Wall, as in: ghc -c Main.hs -Wall. For instance, length always returns an Int, but there's no Fractional instance for Int, so you can't use (/) with it. http://stackoverflow.com/questions/27181476/haskell-parse-error-possibly-incorrect-indentation-or-mismatched-brackets

Haskell If Then Else Indentation

Related -1parse error (possibly incorrect indentation)4Haskell: parse error (possibly incorrect indentation or mismatched brackets) with list comprehension0haskell error parse error (possibly incorrect indentation)1Haskell parse error (possibly incorrect indentation or mismatched brackets)0parse You can't do things like "string" + 2, like in other languages, and you can't do 2.0 / 2. You need to do this in ghci, but in source files let is only used in let ... Also, while the { character and reasonably be about indentation, the others are much less likely to be.

tv<-t2 does not make any sense . Do I need to do this? Have fun! In it, you'll get: The week's top questions and answers Important community announcements Questions that need answers see an example newsletter By subscribing, you agree to the privacy policy and terms

Note: See TracTickets for help on using tickets. However, this is just a quirk of the interpreter--what you enter in GHCi is not the same as what you enter at as a top-level definition in a module. You won't be able to vote or comment. 456parse error (possibly incorrect indentation etc...) Yeah, I'm new to Haskell. (self.haskell)submitted 2 years ago by [deleted]I'm trying to write code to get the standard deviation of You could do | null lst = [] to check that the list is empty, or the more idiomatic: doubleEveryOther [] = [] doubleEveryOther lst | len lst `mod` 2 ...

It has been a lifelong annoyance for me to not know whether that error message is *actually* due to incorrect indentation, or to mismatched brackets. Right now, Haskell sees that you're defining a term doubleEveryOther' acc lst2' and starts looking for an =. And yes, you should read "learn you a Haskell for great good", there are a lot of pitfalls in Haskell. We can actually specialize this to [Double] -> Double if you'd rather use concrete types.

Haskell Indentation Rules

All rights reserved.REDDIT and the ALIEN Logo are registered trademarks of reddit inc.πRendered by PID 30798 on app-531 at 2016-10-23 23:50:36.714372+00:00 running e8b52b1 country code: IL. get redirected here The definiton begun there extends until - a line indented less or equally far is encountered - the keyword 'in' appears - an explicit semicolon ends the definition If a line Haskell If Then Else Indentation If you get frustrated, let the compiler tell you which pattern is missing. Parse Error On Input m = ...

Why is the old Universal logo used for a 2009 movie? this contact form permalinkembedsavegive gold[–]timmy_tofu 0 points1 point2 points 1 year ago(10 children)doubleEveryOther :: [Integer] -> [Integer] doubleEveryOther lst | [] = [] | len lst `mod` 2 == 0 = doubleEveryOther' reverse lst | otherwise Why can't I set a property to undefined? EDIT: Well, also in do blocks. Haskell Guards

The second type error is because you haven't defined sum_of_offsets in a meaningful way, yet. Assuming the lexer is sufficiently modular, this should be easy (at a guess), and not complicate any other part of the compiler. Why do units (from physics) behave like numbers? http://kiloubox.com/parse-error/parse-error-possibly-incorrect-indentationfailed-modules-loaded-none.html Your return type should be IO Integer, and you also need to make a recursive call to get the sum of the remaining values. –Lee Apr 24 '14 at 19:15 add

in ... In particular, where can not run IO actions: at most, it can define e.g. I wouldn't want Haskell to have automatic type coercion; I've learned from other languages how painful that can be.

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What does 'tirar los tejos' mean? Is a rebuild my only option with blue smoke on startup? Veamos algunos casos comunes: Dejar espacios o tabs antes de la cabecera de la función La cabecera de la función debe arrancar justo "contra el margen". haskell share|improve this question edited Nov 21 '11 at 19:28 joaquin 35.3k1486115 asked Oct 24 '11 at 1:59 user1010130 612 Is the whole thing actually indented 2 or 3

permalinkembedsavegive gold[–][deleted] 0 points1 point2 points 2 years ago(10 children)Yeah, I didn't really know what let does. I'm not looking to start that argument all over again, tabs are just fine, but I would recommend spaces since GHC interprets tabs as 8 spaces, and while it may look loops haskell share|improve this question edited Jun 9 '14 at 18:09 Jeremy 2,88182753 asked Apr 24 '14 at 18:55 A77ak 207 1 This won't compile even if you fix the http://kiloubox.com/parse-error/parse-error-haskell.html replace all free occurences of TyVar in tv with the Type in tv while avoiding new captures. –Phyx Oct 24 '11 at 7:17 add a comment| 2 Answers 2 active oldest

Visit the Trac open source project athttp://trac.edgewall.org/ [Haskell-beginners] Re: let indenting problems Daniel Fischer daniel.is.fischer at web.de Mon Mar 2 15:07:27 EST 2009 Previous message: [Haskell-beginners] Re: let indenting problems Next I recommend you do the first for a bit to exercise your brain. I have to double every second item from the right. Are there any historically significant examples?

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Is there a good way to fix that? share|improve this answer answered Oct 24 '11 at 4:03 Satvik 9,97912539 add a comment| Your Answer draft saved draft discarded Sign up or log in Sign up using Google Sign If you intended to use two independent random numbers then use instead pair :: IO String pair = do n1 <- randomRIO (1,10) n2 <- randomRIO (1,10) return (randSeq n1 ++ After the keyword 'let', the position of the start of the next significant token (not whitespace or comments), sets a new indentation level.

I imagine what you want is actually doubleEveryOther' (reverse lst) i.e. The real problem here is that I'm trying to write in a language without knowing anything about it yet.