Well said! And I’d go a step further:
do it for a single implementation first (your favorite one, or Gambit-C if you
don’t have one ;-), with an eye on portability.
Dominique
Perhaps my serious suggestion is: don't worry so much. Just
get a package out there that does any damn thing that might
be useful and then go from there. Separate concerns: a snowball
for XML processing that happens to have some mud in it is a
good place to start -- then separately, start making that snowball
really top-notch. Don't make "getting XML in Scheme perfect"
a pre-condition for "here's a snowball for XML processors".