ANSI Common Lisp 5 Data and Control Flow 5.3 Dictionary of Data and Control Flow
function &rest args+
- Arguments and Values:
function - a function designator.
args - a spreadable argument list designator.
results - the values returned by function.
Applies the function to the args.
When the function receives its arguments via &rest, it is
permissible (but not required) for the implementation to bind
the rest parameter
to an object that shares structure with the last argument to apply.
Because a function can neither detect whether it was called via apply
nor whether (if so) the last argument to apply was a constant,
conforming programs must neither rely on the list structure
of a rest list to be freshly consed, nor modify that list structure.
setf can be used with apply in certain circumstances;
see Section 184.108.40.206 APPLY Forms as Places.
(setq f '+) +
(apply f '(1 2)) 3
(setq f #'-) #<FUNCTION ->
(apply f '(1 2)) -1
(apply #'max 3 5 '(2 7 3)) 7
(apply 'cons '((+ 2 3) 4)) ((+ 2 3) . 4)
(apply #'+ '()) 0
(defparameter *some-list* '(a b c))
(defun strange-test (&rest x) (eq x *some-list*))
(apply #'strange-test *some-list*) implementation-dependent
(defun bad-boy (&rest x) (rplacd x 'y))
(bad-boy 'a 'b 'c) has undefined consequences.
(apply #'bad-boy *some-list*) has undefined consequences.
(defun foo (size &rest keys &key double &allow-other-keys)
(let ((v (apply #'make-array size :allow-other-keys t keys)))
(if double (concatenate (type-of v) v v) v)))
(foo 4 :initial-contents '(a b c d) :double t)
#(A B C D A B C D)
- See Also:
Section 3.1 Evaluation,
Section 220.127.116.11 APPLY Forms as Places
- Allegro CL Implementation Details: