: cr  "\n" . ;
: empty?  dup execute length if 0 else -1 then swap drop ;
: pop  dup execute length 1 - extract swap drop ;
: push  dup execute rot append over ;
: s. stack execute . ;

[] '_ set
: stack '_ ;
stack                     # local variable
    1 swap push set
    2 swap push set s. cr # [    1     2  ]
    pop .           s. cr # 2     [    1  ]
    pop drop
    empty? .              # -1