any pop -                                          discard top element

any1 any2 exch any2 any1                           exchange top two elements

any dup any any                                    duplicate top element

any1..anyn n copy any1..anyn any1..anyn            duplicate top n elements

anyn..any0 n index anyn..any0 anyn                 duplicate arbitrary element

an-1..a0 n j roll a(j-1) mod n..a0 an-1..aj mod n  roll N elements up j times

 ├  any1..anyn clear  ├                            discard all elements

 ├  any1..anyn count  ├  any1..anyn n              count elements on stack

- mark mark                                        push mark on stack

mark obj1..objn cleartomark -                      discard elements down
                                                   through mark

mark obj1 . objn counttomark mark obj1..objn n     count elements down
                                                   to mark