y=123                        /*define a REXX variable, value is 123  */
push y                       /*pushes   123   onto the stack.        */
pull g                       /*pops last value stacked & removes it. */
q=empty()                    /*invokes the  EMPTY  subroutine (below)*/
exit                         /*stick a fork in it, we're done.       */

empty: return queued()       /*subroutine returns # of stacked items.*/