CS2613/labs/L03/first-rest-pattern.rkt

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#lang slideshow
(define (my-map f lst)
(cond
[(empty? lst) empty]
[else (cons (f (first lst))
(my-map f (rest lst)))]))
(define (rainbow p)
(map (lambda (color)
(colorize p color))
(list "red" "orange" "yellow" "green" "blue" "purple")))
(rainbow (circle 10))
(define (rainbow2 p)
(define (color-mapper gr-obj color-list)
(cond
[(empty? color-list) empty]
[else (cons(colorize gr-obj (first color-list))
(color-mapper gr-obj (rest color-list)))]))
(color-mapper p (list "red" "orange" "yellow" "green" "blue" "purple")))
(rainbow2 (circle 20))