Hi friends,
I'm working on a macro that expands into a match statement. It looks
something like
(define-syntax (my-macro stx)
(syntax-case stx ()
[(_ (id1 id2 ...) body ...)
(with-syntax ([match-pattern
(datum->syntax stx (cons 'list (syntax->datum
#'(id1 id2 ...))))])
#'(lambda (expr)
(match expr
[match-pattern body ...])))))
So in effect, it expands
(my-macro (push i) (printf "~v" i)
into
(lambda (expr)
(match expr
[(list push i) (printf "~v" i)]))
Here is the problem: I'd like the first entry of the match list to be
quoted (e.g. 'push) rather than unquoted, as it is above, since 'match'
will interpret this as a free variable, meaning
((my-macro (push i) i) '(dont-push 45)) will evaluate to 45, rather than
fail to match (the desired behavior).
Unfortunately, trusty (quote (syntax->datum stx id1)) and or any variation
thereof will do what it's supposed to: quote whatever expression will
evaluate into whatever I want quoted.
I could just write the quotes into the expressions using the macro, a la
(my-macro ('push i) ...), but Shirly there's a way around this?
Any help would be appreciated. Thanks for your time; I'm loving my
explorations into Racket ^_^
-Paul
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