% --- start of displayed preamble in the book ---
input metaobj
show_empty_boxes:=true;

% --- end of displayed preamble in the book ---
defaultfont:="ptmr8r";
warningcheck:=0;
beginfig(1)
newEmptyBox.a(2cm,1cm) "framed(true)";
a.c=origin;
drawObj(a);
endfig;
end;