libraries

[Michael Vanier <mvanier@bbb.caltech.edu>]

Just parenthetically, I want to say that I'm quite impressed that features
like units and classes are in the PLT scheme libraries as opposed to being
in the core language (unlike virtually all other programming languages).
This is to me an excellent example of the abstractive power of scheme.  It
also provides a clean way of (for instance) implementing variants of the
class system without changing the core language, which is something that is
simply impossible in most languages.

Mike