I'm doing this problem:
6. Write a stream dan-then-dog, where the elements of the stream
alternate between the strings "dan.jpg" and "dog.jpg" (starting with
"dan.jpg"). More specically, dan-then-dog should be a thunk that when
called produces a pair of "dan.jpg" and a thunk that when called
produces a pair of "dog.jpg" and a thunk that when called... etc. Sample
solution: 4 lines.
and I cannot for the life of me understand why the following code does
not produce a properly thunked stream. It evaluates the entries until it
runs out of memory
(define dan "dan.jpg")
(define dog "dog.jpg")
(define (dan-then-dog)
(define (H1 st0 b0)
(cond
[(= b0 1) (H1 (stream-cons dan st0) 0)]
[else (H1 (stream-cons dog st0) 1)]
)
)
(H1 empty-stream 1))
Can somebody please explain why my understanding of Racket streams is
faulty?
Thanks,
Patrick Sweetman
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