Re: and-let* is not composable?

[Panicz Maciej Godek <godek.maciek@gmail.com>]

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>
> If you, or the other people who are confused by syntax-case, can point
> to the parts of the manual that confuse you, so we can clear them up, I
> think we'd all appreciate it.
>
> Fundamentally, syntax-case shouldn't be harder to use than define-macro
> 99% of the time, if you remember
>

As a little addendum to that topic, I just ran across Matthew Flatt's
presentation of Racket macro system,
http://www.infoq.com/presentations/racket,
where he points to a quite good introduction to "define-syntax" macros
by Greg Hendershott: http://www.greghendershott.com/fear-of-macros/

And now that my head is clearer on this regard, I think it is confusing
to call them "syntax-case" macros, because "syntax-case" is rather
auxiliary than essential for defining that sort of macro.

The order of presentation in the manual resembles the one that Hendershott
criticises, namely: first, the syntax-rules macros are presented, which are
an
epiphany once you comprehend them, and then syntax-case is presented as
a different type of macro. However, syntax-case is only a pleasant way to
destructure syntactic information passed to a transformer, and the same
effect could be achieved without using it, by using some more explicit
procedures like syntax->datum. (Furthermore, Hendershott explains
more specifically how do the syntax objects differ from raw scheme forms).
So I believe that at least placing a link to than explanation in the manual
could be a great help for beginners.

Best regards,
M.

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