[plt-scheme] macro question

> My personal opinion is that types do not significantly improve readability
> of programs. A good similarity between data structure and the structure of
> the procedures acting on these data is far more important, I think (this I
> did experience, but not invent by myself, of course)
>

There are many who would agree with you. Types can get in the way of
readability. That, however, may only be true when you are reading to
understand what the code computes and how it computes it (i.e. the
algorithm used by the coder). For those deeply involved with type
systems it provides a means to prove certain invariant properties that
hold about the program. The most obvious, of course, is that type
errors will not occur at runtime. There are many other properties that
can be captured by type systems including safe memory deallocation,
uniqueness, and bounded memory consumption. Would it not be great to
program our PDA using Scheme knowing that our device has enough memory
to run the program? A sophisticated type system can help with that.

Cheers,

Marco