SICP Exercise 3.50 stream-map multiple arguments

Exercise 3.50.  Complete the following definition, which generalizes stream-map to allow procedures that take multiple arguments, analogous to map in section 2.2.3, footnote 12.

(define (stream-map proc . argstreams)
  (if (<??> (car argstreams))
      the-empty-stream
      (<??>
       (apply proc (map <??> argstreams))
       (apply stream-map
              (cons proc (map <??> argstreams))))))

 SOLUTION

 The code and tests are here.

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