anchor.diff:    (fmt "An error of type TYPE-ERROR might be signaled if SEQUENCE is not a~@
           proper sequence."))
   
  -(defparameter *error-bounding-indexes*
  +(defparameter *error-not-valid-index*
  +  (fmt "An error of type TYPE-ERROR is signaled if INDEX is not a~@
  +        valid sequence index for SEQUENCE"))
  +
  +(defparameter *maybe-error-bounding-indexes*
     (fmt "An error might be signaled if START and END are not valid bounding~@
  +	index designators for SEQUENCE, which means that 0 <= START <= L, and~@
  +	either END is NIL or 0 <= END <= L where L is the length of SEQUENCE."))
  +
  +(defparameter *definitely-error-bounding-indexes*
  +  (fmt "An error is signaled if START and END are not valid bounding~@
   	index designators for SEQUENCE, which means that 0 <= START <= L, and~@
   	either END is NIL or 0 <= END <= L where L is the length of SEQUENCE."))
   
  
positive.code: 	     *newitem-item-sequence* *key* *test-test-not* *bounding-indexes* *from-end* *count*
  	     *satisfy-a-two-argument-test*
  	     *error-not-proper-sequence*
  	     *error-bounding-indexes*
  	     *error-count*))
              
  (fundoc 'nsubstitute-if
  
negative.code: 	     *predicate-sequence* *key* *bounding-indexes* *from-end* *count*
  	     *satisfy-a-one-argument-negative-test*
  	     *error-not-proper-sequence*
  	     *maybe-error-bounding-indexes*
  	     *error-count*))
  
  (defparameter *delete-description*
  