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(use-modules (srfi srfi-41))
(define base (stream-from 2))
(define (curry f)
(lambda (x)
(lambda (y)
(f x y))))
(define-stream (stream-ordered-diff xstrm ystrm)
(stream-match xstrm (() '()) ((x . xs)
(stream-match ystrm (() xstrm) ((y . ys)
(cond ((< x y) (stream-cons x (stream-ordered-diff xs ystrm)))
((> x y) (stream-ordered-diff xstrm ys))
(else (stream-ordered-diff xs ys))))))))
(define-stream (sieve input)
(stream-cons
(stream-car input)
(sieve (stream-ordered-diff
(stream-cdr input)
(stream-map ((curry *) (stream-car input)) input)))))
(define euler (sieve base))
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