% --- start of displayed preamble in the book ---
input expressg
% --- end of displayed preamble in the book ---
defaultfont:="ptmr8r";
warningcheck:=0;
beginfig(1)
z1=(0,0);z101-z1=(3cm,0);
for i=2 upto 12:
 z1-z[i]=z101-z[100+i]=(0,(i-1)*5mm);
endfor;

drawdashO(1, 101); % open circle
drawthickO(2,102); % open circle
drawnormalD(3, 103); % black dot
drawnormalCA(4, 104); % closed arrowhead
drawnormalOA(5, 105); % open arrowhead
drawnormalF(6, 106); % fanin
draw z7--z107 dashes;

drawdashA(8, 108);     % arrow
drawdashOA(9, 109);    % open arrowhead
drawnormalOD(10, 110); % open diamond
drawnormalCD(11, 111); % closed diamond
% double closed arrowhead
drawnormalDCA(12, 112);
endfig;
end;