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Haskell equivalent to contains


Haskell equivalent to contains

By : johnmendonca
Date : November 21 2020, 01:01 AM
should help you out Basically i'm trying to scan a string for words that contain a character and count the number of words found that have that character. I'm just wondering if there is a way to check if a word contains a character. , You can use elem:
code :
> 'n' `elem` w
True
wordsWithLetter :: Char -> String -> Int
wordsWithLetter c w
    = length
    $ filter (c `elem`)
    $ words w


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Does F# have an equivalent to Haskell's take?

Does F# have an equivalent to Haskell's take?


By : user1914916
Date : March 29 2020, 07:55 AM
fixed the issue. Will look into that further Yeah, it's called Seq.take. Usage seems to be identical to Haskell's: Seq.take count source. To use it on a list, use List.toSeq first. (Update: Apparently from the comments, this isn't necessary.)
F# equivalent to Haskell's $

F# equivalent to Haskell's $


By : Daniel
Date : March 29 2020, 07:55 AM
may help you . Use the forward/backward pipe operator. Backward pipe operator is used to maintain the orginal order and forward must me turned over. Function Application Operator ($) in F#?
Backward pipe operator
code :
printfn "%d" <| Seq.sum nums
Seq.sum nums |> printfn "%d"
Why are these two haskell functions not equivalent?

Why are these two haskell functions not equivalent?


By : Anuj Kumar
Date : March 29 2020, 07:55 AM
help you fix your problem This is likely coming from the definition of digits, which I'm guessing takes an Integrala => a as one of its arguments. This then places the additional constraint of Integral on the argument to numberDivider2. As it turns out, there is not a type that is an instance of both Fractional and Integral. When you input numeric literals, though, it tries to convert from Num a => a to (Integral a, Fractional a) => a, and in GHCi there are special rules to try to find an instance that also uses Show so that you can print it to the screen. Since no such type exists, you get an error.
Now, the real problem seems to be arising from a misunderstanding of Haskell's number system. You can't use / on all numbers, such as Ints, because / is not defined for those types. You can only use / on fractional types, hence the Fractional typeclass. If you want to convert Ints or Integers to Float or Double to perform a floating point division, you can use fromIntegral to convert them to any Num type, e.g.
code :
a = head $ digits 10 $ fromIntegral num
b = head . tail $ digits 10 $ fromIntegral denom
numberDivider2 :: (Integral a, Fractional b) => (a, a) -> b
numberDivider2 (num, denom) = fromIntegral num / fromIntegral denom
    where
        a = head $ digits 10 num
        b = head . tail $ digits 10 denom
Scala equivalent of Haskell first and second

Scala equivalent of Haskell first and second


By : NoxBit
Date : March 29 2020, 07:55 AM
I hope this helps you . Haskell's Arrows (first and second are among them) are implemented in Scalaz:
Scalaz source
code :
import scalaz._
import Scalaz._

val f = (x: Int) => x + 1
val g = f.second[String]
g("1", 2) //> ("1", 3)

// or with type inference

f second ("1", 2) //> ("1", 3)
equivalent of ruby ...? in haskell

equivalent of ruby ...? in haskell


By : NudeRaider
Date : March 29 2020, 07:55 AM
this will help If you glance at the functions that return Bool, you'll notice that the convention is to use a predicate that when used in code reads like a sentence. For example:
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