% --- start of displayed preamble in the book ---
input metaobj
% Circle produced as before

% --- end of displayed preamble in the book ---

  newCircle.a(btex start etex);
  a.c=origin;

defaultfont:="ptmr8r";
warningcheck:=0;
beginfig(1)
nccircle(a) "angleA(0)",
  "linecolor(blue)","linewidth(1pt)";
drawObj(a);
endfig;
end;