* Jon Dyte
| > (setq test (make-zzz))
| > [ #<Printer Error @ #x5654321>#
|                       ^^^^^^^^^^;; this varies
| Note the right " ]" does not get printed

  attached is a sample run that should illuminate the problem.

#:Erik

CL-USER(1): [In listener #12]
CL-USER(2): (defstruct (zzz (:conc-name nil)
			(:print-function print-zzz))
	      (anything 23))
zzz
CL-USER(3): (defun print-zzz (obj stream level)
	      (write-string "[ " stream)
	      ;; next-lines to deliberatley throw an error
	      (let ((element (car t)))
		(write element :stream stream))
	      (write-string " ]" stream))
print-zzz
CL-USER(4): (make-zzz)
[ #<Printer Error @ #x55a8da>
CL-USER(5): (setq excl::*printer-handle-errors* nil)
nil
CL-USER(6): (handler-case (print (make-zzz))
	       (error (x) (inspect x)))

simple-error @ #x55c6aa = #<simple-error @ #x55c6aa>
   0 Class --------> #<standard-class simple-error>
   1 PLIST --------> The symbol nil
   2 FORMAT-ARGUMENTS -> (t), a proper list with 1 element
   3 FORMAT-CONTROL -> A simple-string (57) that starts <<Attempt at "~1> to t"
[1i] CL-USER(7): (error *)
Error: Attempt to take the car of t which is not listp.
  [condition type: simple-error]
[2] CL-USER(8): :pop
[1i] CL-USER(9): :pop
CL-USER(10): 
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