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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 /<>.