[Haskell-beginners] Map on Nested Lists

[Stephen Tetley]

On 8 April 2010 14:37, Thomas Davie <tom.davie at gmail.com> wrote:
> You can't write a single such function to operate on all the different
> types, .... [SNIP]

Hi Bob (?)

I believe Oleg Kiselyov's deepset functor manages it...

http://okmij.org/ftp/Haskell/typecast.html
http://okmij.org/ftp/Haskell/deepest-functor.lhs

PS - is it Bob or Thomas? thanks.

Best wishes

Stephen