This package is not currently loadable. The package owner has been contacted to assist in correcting this. (klc, 7/11/2008)
As described by Yoshiki Ohshima in a post to the Squeak email list:
"It reads a BNF description and
(if I remember correctly) generates LL(1) parser. You can also
provide semantic actions to the terminal/non-terminal symbols and they
are executed when a rule is reduced.
However, the real cool thing is that the way he has extended the
idea and applied it to the highly-interactive materials. For example,
you can write syntax rules not only in text strings, but also in the
sequence of bitmaps. And, the semantic rules can be arbitrary Squeak
code or even can be SqueakToys tiles so that you can control a morph
with this 'language' (You drop a tile to a semantic rule slot and it
will be executed.)"
See Yoshiki's full post for more details: http://lists.squeakfoundation.org/pipermail/squeak-dev/2003-March/055110.html