model chang uml chang event event event attribut chang event todo restrict care attribut tfm tree model model element chang event sourc event remov associ event todo realli code wai round act associ import repres current perspect act singl end associ tfm namespac equal event properti tree model model element chang remov associ event event chang valu event add associ event namespac equal event properti tree model model element ad add associ event event sourc event delet instanc event tree model model element remov delet instanc event event sourc 