Jon Fairbairn ([EMAIL PROTECTED]) writes:
> On 11 Jul, Wolfram Kahl wrote:
> > [...]
> > The core function here is
> >
> > > (diagonalize (1 :: Integer)) :: [[a]] -> [a]
> >
> > This function diagonalises finite or infinite lists
> > with arbitrary finite or infinite element lists.
> >
> > [..]
> I got rather lost in the ensuing discussion, so I've composed this
> reply from back here. It seems to me that the core function is (//),
> which can be written like this:
>
> > module Diagonalise ((//)) where
> > import List
>
> A diagonalisation function that doesn't use numbers.
>
> > (//):: [a] -> [b] -> [(a,b)]
>
> [...]
> Or have I totally lost it?
I confess guilty to have diverged from this simpler problem
> (//) :: [a] -> [b] -> [(a,b)]
to the more general problem
> diagonalise :: [[a]] -> [a]
The first can be reconstructed from the latter via:
> (//) as bs = diagonalise [ [ (a,b) | b <- bs ] | a <- as ]
HTH!
Wolfram
