Alyssa P. Hacker proposes to use a simpler version of stream-flatmap in negate, lisp-value, and find-assertions. She observes that the procedure that is mapped over the frame stream in these cases always produces either the empty stream or a singleton stream, so no interleaving is needed when combining these streams.
a. Fill in the missing expressions in Alyssa's program.
(define (simple-stream-flatmap proc s) (simple-flatten (stream-map proc s))) (define (simple-flatten stream) (stream-map <??> (stream-filter <??> stream)))
b. Does the query system's behavior change if we change it in this way?
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