On 11/20/2014 3:10 PM, "Ola Fosheim Grøstad" <ola.fosheim.grostad+dl...@gmail.com>" wrote:
On Thursday, 20 November 2014 at 22:47:27 UTC, Walter Bright wrote:
On 11/20/2014 1:55 PM, deadalnix wrote:
All of this is beautiful until you try to implement a quicksort
in, haskell.

[…]

Monads!

I think Deadalnix meant that you cannot do in-place quicksort easily in Haskell.

That's correct.

Non-mutating quicksort is easy, no need for monads:

quicksort []     = []
quicksort (p:xs) = (quicksort lesser) ++ [p] ++ (quicksort greater)
     where
         lesser  = filter (< p) xs
         greater = filter (>= p) xs

https://www.haskell.org/haskellwiki/Introduction#Quicksort_in_Haskell

Except that isn't really quicksort. Monads are the workaround functional languages use to deal with things that need mutation.

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