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vector-push, vector-push-extend [Function]

vector-push new-element vector => new-index-p

vector-push-extend new-element vector &optional extension => new-index

Arguments and Values::

new-element--an object.

vector--a vector with a fill pointer.

extension--a positive integer. The default is implementation-dependent.

new-index-p--a valid array index for vector, or nil.

new-index--a valid array index for vector.

Description::

vector-push and vector-push-extend store new-element in vector. vector-push attempts to store new-element in the element of vector designated by the fill pointer, and to increase the fill pointer by one. If the (>= (fill-pointer vector) (array-dimension vector 0)), neither vector nor its fill pointer are affected. Otherwise, the store and increment take place and vector-push returns the former value of the fill pointer which is one less than the one it leaves in vector.

vector-push-extend is just like vector-push except that if the fill pointer gets too large, vector is extended using adjust-array so that it can contain more elements. Extension is the minimum number of elements to be added to vector if it must be extended.

vector-push and vector-push-extend return the index of new-element in vector. If (>= (fill-pointer vector) (array-dimension vector 0)), vector-push returns nil.

Examples::

      (vector-push (setq fable (list 'fable))
                   (setq fa (make-array 8
                                        :fill-pointer 2
                                        :initial-element 'first-one))) =>  2
      (fill-pointer fa) =>  3
      (eq (aref fa 2) fable) =>  true
      (vector-push-extend #\X
                         (setq aa
                               (make-array 5
                                           :element-type 'character
                                           :adjustable t
                                           :fill-pointer 3))) =>  3
      (fill-pointer aa) =>  4
      (vector-push-extend #\Y aa 4) =>  4
      (array-total-size aa) =>  at least 5
      (vector-push-extend #\Z aa 4) =>  5
      (array-total-size aa) =>  9 ;(or more)
     

Affected By::

The value of the fill pointer.

How vector was created.

Exceptional Situations::

An error of type error is signaled by vector-push-extend if it tries to extend vector and vector is not actually adjustable.

An error of type error is signaled if vector does not have a fill pointer.

See Also::

adjustable-array-p , fill-pointer , vector-pop