[plt-scheme] Natural Language parsing in CS1

> I think Todd's exercise is a decent introduction to parsing, and an
> understanding of this is vital to see why strict symbolic
> grammar-and-parser approaches do not scale.

...if that is the point to the exercise.  Otherwise you will have
another generation of students thinking this is how NL is parsed, and
will be in no position whatsoever to appreciate how something like
Babelfish works.  (YC's message, where he effectively says he has read
multiple AI books that mentioned NLP and yet they all left him
unprepared to understand Eli's message, is telling.)

Moreover, it's actually possible for an intro course student to
understand (a glimpse of) what's going on below the real thing.  If
that were impossible, that would be different.  But just as the kind
of parser Todd mentions was a glimpse of what happened in NLP systems
20 years ago, a very different system offers a perfectly reasonable
glimpse of what happens in NLP systems today.  And I think that's why
you're getting a strong reaction from Eli and me.

As for Eli's comment that the two kinds of languages (NL and PL) are
processed completely differently, well, maybe that will change with
time.  Once you get past parsing and compilation to intent and errors,
what people say in a PL resembles what they say in an NL....

Shriram