HELP DEST John Williams, August 1986
dest(<list>) -> tail -> head
This procedure returns both the HD and the TL of the given list, so that
dest(l) -> l -> x;
is equivalent to (and a little faster than)
hd(l) -> x;
tl(l) -> l;
DEST could be defined as:
define dest(l) -> t -> h;
hd(l) -> h;
tl(l) -> t;
enddefine;
See also:
HELP * HD
HELP * TL
HELP * DESTPAIR
TEACH * LISTS
--- C.all/help/dest ----------------------------------------------------
--- Copyright University of Sussex 1987. All rights reserved. ----------Author: John Williams, August 1986