Another minor issue.

In the code below:

   (define-syntax define-stream
     (syntax-rules ()
       ((define-stream (name . formal) body0 body1 ...)
         (define name (stream-lambda formal body0 body1 ...)))
       ((define-stream (name formals ...) body0 body1 ...)
         (define name (stream-lambda (formals ...) body0 body1 ...)))))

The second case is redundant since (name . formal) matches any pair,
including all those matched by (name formals ...).

Aziz,,,