- (awhile test xpr . xprs)syntax
Anaphoric version of while.
The body xpr . xprs is evaluated as often, as the test is true. As usual, the result of this test, which often is the result of a poll operation, is named it and can be referenced in the body.
(let ((lst '(1 2 3 4 5 #f)) (res '())) (awhile (car lst) (set! res (cons (car lst) res)) (set! lst (cdr lst))) res)
Of course, this is not the preferred programming style in Scheme ...