The following code produces '(1 2 3 4)
(define-syntax (collect stx)
(syntax-case stx (define)
[(_ (define id val) rest ...)
#'(let ([id val])
(collect rest ...))]
[(_ (macro arg ...) rest ...)
(syntax-local-value #'macro (lambda () #f))
(let ([expanded (local-expand #'(macro arg ...) 'expression (list
#'define))])
(println expanded)
#`(collect #,expanded rest ...))]
[(_ a rest ...)
#'(cons a (collect rest ...))]
[(_)
#'(list)]))
(define-syntax-rule (my-define stuff ...)
(define stuff ...))
(collect 1 2 (define x 3) x 4)
I would like `(collect 1 2 (my-define x 3) x 4)` to produce the same
result. But instead I get the error message "let-values: cannot bind
tainted identifier in: x"
"OK, maybe this is impossible" I thought, and moved on to what I should
have been working on anyway. But now I see that `class*` does seem to
recognize arbitrary macros. The following example shows that `class*`
seemingly understands my arbitrary `define-foo` macro:
(define-syntax-rule (define-foo)
(define/public (foo)
(list this 'foo)))
(define my-class%
(class* object% ()
(super-new)
(define-foo)))
(define c (new my-class%))
(send c foo)
How does `class*` understand my `define-foo` macro? And can the same
technique be used to fix my `collect` macro?
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