creat model element graph terminolog edg model element link model element make sens exist itelf param meta type type model element creat param sourc sourc model element link param destin destin model element link param relationship descr textual descript describ sourc relat destin action creat edg model element object meta type object sourc object destin relationship descr messag format format relationship descr object displai text tree model element displai sourc displai text tree model element displai destin meta type meta type sourc sourc dest destin 