why is this code giving me a ran out of memory error code on racket? -


i need create defintion outputs picture of traffic light depending on string either green yellow or red , whatever string determines bulb solid

(define green-light   (overlay (above (circle 15 "solid" "green")                   (circle 15 "outline" "yellow")                   (circle 15 "outline" "red"))            (rectangle 50 100 "outline" "black")))  (define yellow-light   (overlay (above (circle 15 "outline" "green")                   (circle 15 "solid" "yellow")                   (circle 15 "outline" "red"))            (rectangle 50 100 "outline" "black")))  (define red-light   (overlay (above (circle 15 "outline" "green")                   (circle 15 "outline" "yellow")                   (circle 15 "solid" "red"))            ( rectangle 50 100 "outline" "black")))  (check-expect (trafficlightstate "green")               (overlay (above (circle 15 "solid" "green")                               (circle 15 "outline" "yellow")                               (circle 15 "outline" "red"))                        (rectangle 50 100 "outline" "black")))  (check-expect (trafficlightstate "yellow")               (overlay (above (circle 15 "outline" "green")                               (circle 15 "solid" "yellow")                               (circle 15 "outline" "red"))                        (rectangle 50 100 "outline" "black"))) (check-expect (trafficlightstate "red")               (overlay (above (circle 15 "outline" "green")                               (circle 15 "outline" "yellow")                               (circle 15 "solid" "red"))                        (rectangle 50 100 "outline" "black")))   (define (trafficlightstate color)    (cond [(trafficlightstate "green") (place-image green-light)]         [(trafficlightstate "yellow") (place-image yellow-light)]         [(trafficlightstate "red") (place-image red-light)]))

the issue in trafficlightstate function. if click “check syntax” button , hover on name in drracket, you’ll see of hint what’s wrong it:

all arrows point places trafficlightstate function used, , indeed, it’s being used 3 times inside itself. is, trafficlightstate function calling itself, known recursive function.

since trafficlightstate keeps calling itself, enters infinite loop, consuming more , more memory until runs out. isn’t want, should reconsider way cond works , adjust function fix accordingly.

it might use stepper in drracket step through execution of program in order understand what’s going on. click “step” button in menu , click arrows move through execution of program 1 step @ time.


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