Matching templates against a tree - any ideas?

[Tim Peters]

[John Skaller]
> ...
> Finally, although I am not sure I completely understood,
> I just read an article (posted to comp.theory) which I think proves
> that arbitrary context free languages can be parsed in O(N).

Mark Anthony Hopkins?  He's certainly, umm, interesting.

if-you're-not-sure-you-completely-understood-"laws-of-form"-
    either-it's-not-a-coincidence-ly y'rs  - tim