adjusting displaced arrays

[David C. Plummer <DCP@SCRC-QUABBIN.ARPA>]

    Date: 15 May 1986 19:26-EDT
    From: NGALL@G.BBN.COM

Nit picking.

    (DEFUN AREF (ORIGINAL-ARRAY &REST SUBSCRIPTS)
      (LABELS ((FOO (ARRAY INDEX)
It would be a tad clearer if FOO were called 1D-AREF
		 (MULTIPLE-VALUE-BIND (NEW-ARRAY OFFSET) (DISPLACED-ARRAY-P ARRAY)
		   (IF (NULL NEW-ARRAY)
		       (ROW-MAJOR-AREF ARRAY INDEX)
ROW-MAJOR-AREF isn't a CL primitive.  Our system calls is SYS:%1D-AREF.
It's not clear you need to call it row-major-aref either, as the
row-major part of the computation is dealt with below.
		       (MULTIPLE-VALUE-CALL #'FOO
You don't need multiple-value-call; FOO takes exactly two arguments.
					    NEW-ARRAY
					    (+ INDEX OFFSET)))))
	  (FOO ORIGINAL-ARRAY
	       (APPLY #'ARRAY-ROW-MAJOR-INDEX ORIGINAL-ARRAY SUBSCRIPTS))))

I think this is a reasonable extension, but I think it also must warn
users that since arrays are adjustable, and indirect chain can be
changed, and therefore, the target of repeated calls to
DISPLACED-ARRAY-P should not be cached.