collapseos/blk/307

CODE DUP ( a -- a a )
    HL POP, chkPS,
    HL PUSH, HL PUSH,
;CODE

CODE ?DUP
    HL POP, chkPS,
    HL PUSH,
    HLZ, IFNZ, HL PUSH, THEN,
;CODE

CODE DROP ( a -- )
    HL POP,
;CODE