• fill-pointer vector → fill-pointer
• (setf (fill-pointer vector) new-fill-pointer)

• vector - a vector with a fill pointer.
• fill-pointer, new-fill-pointer - a valid fill pointer for the vector.

Accesses the fill pointer of vector.

(defparameter *array* (make-array 8 :fill-pointer 4)) 

→

*ARRAY*



*array* 

→

#(NIL NIL NIL NIL) 



(fill-pointer *array*) 

→

4 



(dotimes (i (length *array*))
  (setf (aref *array* i) (* i i))) 

→

NIL



*array* 

→

#(0 1 4 9)



(setf (fill-pointer *array*) 3) 

→

3 



(fill-pointer *array*) 

→

3 



*array* 

→

#(0 1 4)



(setf (fill-pointer *array*) 8) 

→

8 



*array* 

→

#(0 1 4 9 NIL NIL NIL NIL) 

None.

None.

Should signal an error of type type-error if vector is not a vector with a fill pointer.

Function MAKE-ARRAY, Function LENGTH

There is no operator that will remove a vector's fill pointer.