[plt-scheme] Re: plt-scheme type of language

Your purported inability to express this more clearly (you're very
clear, in fact) is actually very instructive, because it helps me
understand what you are having difficulty articulating.

You also have a key insight, which is that the problem w/ that section
of PLAI is not what IS there but what isn't.

What is there is, I think, a fairly useful *academic* introduction.
It was never intended for an industrial person to quickly get a gist
of what is going on.  In a sense, it's written backwards: only after
you understand what is happening are you given told what does and
doesn't make sense, by which time (a) most people have stopped reading
and (b) a few like you who haven't are now not clear what's a tree and
what's the forest.  It is conceivable that putting the back up front,
and then repeating it in technical detail, can have some value.

In general, PLAI does not do a good job of the "isn't"s.  What isn't
meaningful about "strong typing"?  What isn't good about aliasing?
What isn't right with analogies about objects?  Etc.  All these things
have to be gleaned from being in a class taught by the faculty who use
it, since they aren't written down.

Shriram