I'm still trying to grok macros - which are amazing, but hard. I'd like to
know if it is possible capture part of the following expression
(display (+ 2 (bar (+ 1 2))))
if "bar" is a literal in the macro, I would like to capture body0 as (+ 1
2) and body1 as (display (+ 2 ...)).
This is a totally artificial example.
Here's what I have:
(define-syntax (define-foo stx)
(syntax-case stx (bar)
([_ (name param) (body1 (bar . body0))]
(syntax (define (name param)
(body1 (+ 3 . body0)))))))
(define-foo (foof env)
(display (bar (+ 1 2))))
This works...and expands to.
(define (foof env)
(display (+ 3 (- 1 (+ 1 2)))))
(Note that -1 has been substitute for the "bar" literal").
This expression fails with "bad syntax"
(define-foo (foog env)
(display (+3 (bar (- 1 (+ 1 2))))))
I don't seem be to able to capture (display (+3 )) as separate from (bar
(-1 (+ 1 2)))
Is this possible to capture?
Thanks for any help and insights into macros
Chad
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