@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1990-1995, 1998-1999, 2001-2012 Free Software Foundation, Inc.
+@c Copyright (C) 1990-1995, 1998-1999, 2001-2013 Free Software
+@c Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@node Lists
@chapter Lists
element number zero. If the length of @var{list} is @var{n} or less,
the value is @code{nil}.
-If @var{n} is negative, @code{nth} returns the first element of
-@var{list}.
+@c Behavior for -ve n undefined since 2013/08; see bug#15059.
+@ignore
+If @var{n} is negative, @code{nth} returns the first element of @var{list}.
+@end ignore
@example
@group
@group
(nth 10 '(1 2 3 4))
@result{} nil
-@end group
-@group
-(nth -3 '(1 2 3 4))
- @result{} 1
(nth n x) @equiv{} (car (nthcdr n x))
@end group
words, it skips past the first @var{n} links of @var{list} and returns
what follows.
-If @var{n} is zero or negative, @code{nthcdr} returns all of
+@c "or negative" removed 2013/08; see bug#15059.
+If @var{n} is zero, @code{nthcdr} returns all of
@var{list}. If the length of @var{list} is @var{n} or less,
@code{nthcdr} returns @code{nil}.
@result{} nil
@end group
@group
-(nthcdr -3 '(1 2 3 4))
+(nthcdr 0 '(1 2 3 4))
@result{} (1 2 3 4)
@end group
@end example
@node Rearrangement
@subsection Functions that Rearrange Lists
@cindex rearrangement of lists
+@cindex reordering, of elements in lists
@cindex modification of lists
Here are some functions that rearrange lists ``destructively'' by