Questions tagged [Haskell] (58)

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How called functional programming languages, and why they are little used for commercial development?

Lately, very interested in functional programming, especially Haskell, but I almost didn't find it vacancies. Afraid to study them, not knowing whether I will pay it.
lilla_Sau asked April 8th 20 at 17:11
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A Haskell program how to display data structures?

Data structure: country; reserve; number of species of rare animals in the reserve. Create two queries, allowing you to list "Country – a number of reserves" and a list of those nature reserves where many rare species. Tell me how display a list of Country - the number of reserves An example of the structure i1 = Reserves {...
edythe.McCullou asked April 3rd 20 at 18:03
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How to do the following functions in Haskell?

Urgently need help!!! Who can help me please!! Date: data B = T | F deriving Show data Nat = Zero | S Nat data ZInt = Z Nat Nat deriving Show a) Make functions: oddN :: Nat -> B fibonacci :: Nat -> Nat isTeilerN :: Nat -> Nat -> B -- checks whether it is divisible first number by the second ggtN :: Nat -> Na...
Else_Kautzer asked April 3rd 20 at 18:00
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Why shows oshibku? like all true? and how to fix?

Good day! Shows error requires let and how to fix? The program not entirely ,the problem is in the validation block to enter letters In this part of the validation block letters and block check digits are the same but digital does not swear,and the validation block letters arguing..
hollis.Brekke55 asked April 3rd 20 at 17:08
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How to determine the estimate of the complexity of the algorithm?

You need to explicitly estimate the complexity of the algorithms given below, read a lot on this topic, but found no examples of language Haskell 1) isSorted :: (Ord a) => (a->a->Bool) -> [a] -> Bool isSorted cmp xs = and (zipWith cmp xs (tail xs)) 2) mult :: Integer -> Integer -> Integer mult n 0 = 0...
maia_Powlowski asked April 2nd 20 at 16:30
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Expansion of the Fibonacci numbers to negative numbers, what does it mean?

Task: Define the two functions in the language Haskell (recursive and using tools lists) for all the options. Tell me what does the Extension of the Fibonacci numbers to negative numbers?
Dewayne_Beah asked April 2nd 20 at 15:59
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What is the cause of the error when installing package haskell?

Trying to install a package... Get the following encoding:cabal install encoding Resolving dependencies... Configuring encoding-0.6.6... Failed to install encoding 0.6.6 Build log ( /home/haskell/.cabal/logs/ghc-8.4.4/encoding-0.6.6-FpSxS0hB2DcAOz2YiS2hId.log ): cabal: Entering directory '/tmp/cabal-tmp-21138/encoding-0.6.6...
Jacky.Cartwright asked March 25th 20 at 13:41
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How to embed GHC into your app (in Qt)?

I'm not kidding, has anyone done this? While studying and feeling like a motorcycle to drag myself to the balcony (someone does)
paris.Wilkins asked March 25th 20 at 13:05
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How does the composition in Haskell?

Please explain how does this function: import Data.Char digitSum :: Int -> Int digitSum = sum.map digitToInt.show how is it that the function show converts a number to a string, and gives not to the function digitToInt, and in the map function itself as the first argument placed at map. Logically, the show should pass i...
avery asked March 25th 20 at 11:45
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Functions for working with string in Haskell?

Working with encrypted text, I need to write 2 functions that does not work, one should take all the characters, except for letters, the second to return these characters in the new text. (Letters in one register only great) Example: I'M GOING, I'LL BE THERE. "HELLO WORLD!" GOOD NIGHT... After the first function turns a st...
Easton_Sip asked March 23rd 20 at 18:56