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Accessor NTH

Syntax

  • nth n listobject
  • (setf (nth n list) new-object)

Arguments and Values

Description

nth locates the nth element of list, where the car of the list is the "zeroth" element. Specifically,

(nth n list) ≡ (car (nthcdr n list))

nth may be used to specify a place to setf. Specifically,

(setf (nth n list) new-object) ≡ (setf (car (nthcdr n list)) new-object)

Examples

(nth 0 '(foo bar baz))

FOO

(nth 1 '(foo bar baz))

BAR

(nth 3 '(foo bar baz))

NIL

(defparameter *0-to-3* (list 0 1 2 3))

*0-TO-3*

(setf (nth 2 *0-to-3*) "two")

"two"

*0-to-3*

(0 1 "two" 3)

Side Effects

None.

Affected By

None.

Exceptional Situations

None.

See Also

Example Implementation

To be done.

Notes

None.

\issue{DOTTED-LIST-ARGUMENTS:CLARIFY}