Mattias Bengtsson wrote:
I found myself writing this for an Euler-problem:
digits :: Int -> [Int]
digits i | i < 10 = [i]
| otherwise = i `mod` 10 : digits ( i `div` 10 )
And i realised it was quite some time ago (before this function) i had
actually written any explicitly recursive function.
Back in my Introduction to Functional Programming course, Daan Leijen
demonstrated how to print integers in Haskell using function
composition. Something along the lines of:
printint :: Int -> [Char]
printint = map chr . map (+0x30) . reverse . map (`mod` 10) . takeWhile
(>0) . iterate (`div`10)
You can easily translate a number to a list of digits without explicit
recursion.
Regards,
Reinier
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