Re: [Haskell-cafe] reversing big list with constant heap space used

On Wed, 16 May 2007, Sergey Perminov wrote:

How to solve task of reversing big list with constant heap space used?

By avoiding 'reverse'?

Amount of heap space used grows exponentially in following examples:

1: main = putStrLn.show.head $reverse [1..10000000]

Data.List.last I think that in every particular case you have to find out how to avoid 'reverse'. Especially if you have two 'reverse's like in reverse . dropWhile p . reverse there are more efficient solutions.