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#haskell

67 posts39 participants1 post today
Continued thread
Public
Tariq

I've tried debugging by pen and paper to work through what foldr and the helper function does step by step using the definition from the online course:

foldr :: (a -> b -> b) -> b -> [a] -> b
foldr f y [] = y
foldr f y (x:xs) = f x (foldr f y xs)

----

f 2 [1,1] = f 2 ( f 1 [1])
= f 2 ( f 1 ( f 1 [] ) )
= f 2 ( f 1 [1] )
= f 2 ( [1,1] )
= [2,1]

... ok I think I found the bug

so my logic is wrong.

#haskell
Public
Tariq

stuck on a #haskell puzzle

aim return a list of all occurrences of the largest Int in a list

my solution has a bug

[2,1,1] it returns [2,1] not [2]

--------

-- Examples:
-- largest [] ==> []
-- largest [1,3,2] ==> [3]
-- largest [1,3,2,3] ==> [3,3]

largest :: [Int] -> [Int]
largest xs = foldr largestHelper [] xs

largestHelper :: Int -> [Int] -> [Int]
largestHelper x [] = [x]
largestHelper x (y:xr)
| x > y = x:xr
| x == y = x:y:xr
| otherwise = y:xr

--------

help!

Public
Francesco

cabal-install 3.14.2.0 released
discourse.haskell.org/t/cabal-
With a number of very important regression fixes! Try it now!

Many thanks to our release manager Mikolaj Konarski and all contributors!
Boosts for reach appreciated!

Haskell Community · Cabal-install 3.14.2.0 releasedCabal team is happy to announce the release of cabal-install tool version 3.14.2.0 and related libraries. Early adopters that have switched to the vanilla ghcup channel can already install it via ghcup install cabal 3.14.2.0 && ghcup set cabal 3.14.2.0 while others may want to wait for the main ghcup channel to include the release, possibly with more architectures supported than on the vanilla channel. Another early adopter option is ghcup --no-cache install cabal -u 'https://gitlab.haskell.o...
#haskell#cabal
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