% --- start of displayed preamble in the book --- input metaobj % --- end of displayed preamble in the book --- defaultfont:="ptmr8r"; warningcheck:=0; beginfig(1) setObjectDefaultOption("Tree") ("hideleaves")(true); t:=T_(new_Circle(btex foo etex)) (new_HFan_(1cm,0)("filled(true)"), Tf, _T(new_RBox(btex bar etex)) (new_HFan(1cm,0)) ) ("Dalign(center)"); Obj(t).c=origin; draw_Obj(t); endfig; end;