15.2.21 fill-pointer [Accessor]

fill-pointer vector ⇒ fill-pointer

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

Arguments and Values::

vector—a vector with a fill pointer.

fill-pointer, new-fill-pointer—a valid fill pointer for the vector.

Description::

Accesses the fill pointer of vector.

Examples::

 (setq a (make-array 8 :fill-pointer 4)) ⇒  #(NIL NIL NIL NIL)
 (fill-pointer a) ⇒  4
 (dotimes (i (length a)) (setf (aref a i) (* i i))) ⇒  NIL
 a ⇒  #(0 1 4 9)
 (setf (fill-pointer a) 3) ⇒  3
 (fill-pointer a) ⇒  3
 a ⇒  #(0 1 4)
 (setf (fill-pointer a) 8) ⇒  8
 a ⇒  #(0 1 4 9 NIL NIL NIL NIL)

Exceptional Situations::

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

See Also::

make-array , length

Notes::

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