update example
update example

advance() is non-const

frib-high-level-controls/FLAME,frib-high-level-controls/FLAME,frib-high-level-controls/FLAME,frib-high-level-controls/FLAME,mdavidsaver/jmbgsddb,frib-high-level-controls/FLAME,mdavidsaver/jmbgsddb,mdavidsaver/jmbgsddb,frib-high-level-controls/FLAME,mdavidsaver/jmbgsddb