[plt-scheme] Analyze error I don't grok

Start DrScheme, select R5RS as the language level and enter the code:

(define lst
  (lambda (n)
    (if (<= n 0)
        '()
        (cons n (lst (- n 1))))))

into the editor.  Click "Analyze".  It goes red.  Right-click the red and
pick "Show Errors" -- why does it give that error?

-- 
MJR| 
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