%
% cycle through the products, create list of
% newly tabulated items, adding them to the
% cart level of tabulation
%
empty
first\?
{
 {
%
% process the product
%
  !\
%
% newly selected add to cart for product
%
  "Tabulated" \_ zeronull
  "Cart" \_ zeronull add
  dup "Cart" \!
%
% clear the newly tabulated
%
  0 "Tabulated" \!
%
% add to the string list of newly tabulated items
%
  &" '" _\\ & &"' "
  &
%
% next product
%
  final\? ?
 } loop
 pop
} if