OK, I took some time to mock out some Scheme: here are both behaviours you've seen:
(define cclosures
(lambda (values)
(cond ((null? values) '())
(else (cons (lambda (x) (* (car values) x))
(cclosures (cdr values)))))))
(define cclosures2
(let ((val -1))
(lambda (values)
(cond ((null? values) '())
(else
(begin
(set! val (car values))
(cons (lambda (x) (* val x))
(cclosures2 (cdr values)))))))))
(define clprint
(lambda (closures)
(map (lambda (fn) (fn 2)) closures)))
> (clprint (cclosures '(0 1 2)))
(0 2 4)
> (clprint (cclosures2 '(0 1 2)))
(4 4 4)
cclosures uses the equivalent ofdeclaring my $i inside the foreach loop: it defines a new variable called val for every iteration.
cclosures2 uses the equivalent of declaring my $i outside the foreach loop: val gets reassigned with every iteration.
Notice the closure closes over the variable, not the value. So when the variable is reassigned, the value inside the closure changes too.
HTH
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