On Wed, 8 Sep 2021, Iain Duncan wrote:
(define (s4m-process-sexp sexp)
It is entirely a point of style, but I think I would rather make a
'deepmap' helper function. Untested, but something like:
(define (deepmap f x)
(if (not (list? x))
(f x)
(cons (deepmap f (car x))
(deepmap f (cdr x)))))
This also has the convenient side effect of allowing you to e.g. avoid the
contents of quotes.
I also noticed I could thus dispense with the oneline macro all together now by
doing:
(define (s4m-run-expr sexp-str)
(let ((input-sexp (string->sexp sexp-str)))
(eval '(eval (s4m-process-sexp input-sexp)))))
The problem with this is that, since the eval runs in the s4m-run-expr's
environment, you lose the lexical scope of the caller. It would be nice
to be able to say (let ((x 5)) (s4m-run-expr "something with x"))
I think you can evaluate things in the calling environment with a bacro,
but that's hardly simpler than a regular macro.
(define-macro (s4m-run-sexp-macro sexp)
`(eval (s4m-process-sexp ,sexp)))
Can just be:
(define-macro (s4m-run-sexp-macro sexp)
(s4m-process-sexp sexp))
-E
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