Re: contractual programming

[Jeff Dalton <jeff@aiai.edinburgh.ac.uk>]

jap writes:

> What I would prefer is a macro model that works harmoniously with the
> module mechanism...and that's the difficulty.  Unfortunately the
> "macros that work" model doesn't seem to hold up in this context.
> Also, I and others that I have talked to don't want to be restricted
> to syntax-rules style definitions, but rather want to be able to write
> arbitrary expander functions.  The difficulty is in making the use of
> the macro transparent to the client...which is why the principle of
> the syntactic closure offers promise.  The EuLisp group have been
> working on this issue for a couple of years (but only part-time) and
> although we hve come near to a reasonable solution, it breaks down
> with macro generating macros.

Some of the recent Scheme solutions look fairly reasonable, though
I still feel I need more experience with them before I can say whether
they do what I want.  

What is it that's wrong with "macros that work", by the way?
Do they break down in more cases than the Common Lisp approach?

-- jeff