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nthcdr (Function)

— Function: nthcdr n list tail
Arguments and Values:

n—a non-negative integer.

list—a list, which might be a dotted list or a circular list.

tail—an object.


Returns the tail of list that would be obtained by calling cdr n times in succession.

 (nthcdr 0 '())  NIL
 (nthcdr 3 '())  NIL
 (nthcdr 0 '(a b c))  (A B C)
 (nthcdr 2 '(a b c))  (C)
 (nthcdr 4 '(a b c))  ()
 (nthcdr 1 '(0 . 1))  1

 (locally (declare (optimize (safety 3)))
   (nthcdr 3 '(0 . 1)))
 Error: Attempted to take CDR of 1.
Exceptional Situations:

Should signal an error of type type-error if n is not a non-negative integer.

For n being an integer greater than 1, the error checking done by (nthcdr n list) is the same as for (nthcdr (- n 1) (cdr list)); see the function cdr.

See Also:

cdr, nth, rest