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[Scheme-reports] Are generated toplevel definitions secret?
R5RS didn't specify this, which was always a very annoying obstacle to
(define x 1)
(let-syntax ((foo (lambda (e)
(define x 2)
(foo)) ;==> 2
x ;==> NOT SPECIFIED IF IT SHOULD BE 1 or 2
It seems from my reading on p. 15 that R7RS doesn't specify it either.
In otehr words, definitions introduced in macros can possibly shadow toplevel
bindings, which is a major obstacle to safe hygienic macro programming.
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