HELP TL updated Mark Rubinstein October 1985
tl(list) -> tail-of-list;
list -> tl(list);
This procedure (and its *UPDATER) access the tail of a list. In POP11
(as in LISP and PROLOG) we talk about lists as having two parts, its
head (see HELP * HD) which is the first element and its tail which is
the list of all elements but the first. Thus:-
vars x;
[a b c] -> x;
tl(x) =>
** [b c]
[d e f] -> tl(x);
x =>
** [a d e f]
tl(x) =>
** [d e f]
TL expands dynamic lists, (see HELP * PDTOLIST).
See also HELP * BACK, *HD, * SYSWORDS /::, *SYSWORDS /<>.Author: updated Mark Rubinstein October 1985