% primitive recursion
/pfact {
{1} {*} primrec}.
%linear recursion
/lfact {
{dup 0 eq}
{pop 1}
{dup pred}
{*}
linrec}.
% general recursion
/gfact {
{0 eq}
{succ}
{i *}
genrec}.
% binary recursion
/fib {
{2 lt} {} {pred dup pred} {+} binrec}.