SICP演習問題4.74
;; exercise 4.74 (define (simple-stream-flatmap proc stream) (simple-flatten (stream-map proc stream))) (define (simple-flatten stream) (stream-map stream-car (stream-filter pair? stream)))
;; exercise 4.74 (define (simple-stream-flatmap proc stream) (simple-flatten (stream-map proc stream))) (define (simple-flatten stream) (stream-map stream-car (stream-filter pair? stream)))