[Haskell-beginners] Question about data structures

[Stephen Tetley]

On 24 November 2010 21:12, Russ Abbott <russ.abbott at gmail.com> wrote:
[Trunc]

> Another example is to imagine a Tree in which the leaves contain "objects."
>  If I want to change a property of one of those leaf objects, I am forced to
> rebuild all the ancestor nodes of that leaf down to rebuilding the root.

Specifically for re-writing trees, attribute grammars are probably
more concise than OO or functional methods.

Haskell has an attribute grammar pre-processor UUAG available.

http://hackage.haskell.org/package/uuagc

Zippers too may or may not be a convenience for this sort of manipulation.