COMMENT ⊗   VALID 00014 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002	%tracingall
C00003 00003	iff known left_arrow: cmchar "Leftward arrow"
C00005 00004
C00007 00005
C00012 00006
C00016 00007
C00018 00008
C00022 00009
C00035 00010
C00038 00011
C00042 00012
C00043 00013
C00044 00014
C00046 ENDMK
C⊗;
%tracingall
iff known left_arrow: cmchar "Leftward arrow";
compute_spread(.45x_height#,.55x_height#);
beginchar(left_arrow,18u#,v_center(spread#+rule_thickness#)); less_rounded;
adjust_fit(0,0); pickup crisp.nib;
pos1(rule_thickness,90); pos2(rule_thickness,90); pos3(bar,0); pos4(bar,0);
y0=y1=y2=math_axis; x1+.5rule_thickness=round(w-u); lft x0=round u;
y3-y0=y0-y4=.24asc_height+eps; x3=x4=x0+3u+eps;
pos5(bar,angle(z4-z0)); z5l=z0; pos6(bar,angle(z3-z0)); z6l=z0;
z9=.381966[.5[z3,z4],z0];
numeric t; path p; p=z4r{z9-z4}..z6r;
t=xpart(p intersectiontimes((0,y2l)..(w,y2l))); x2=xpart point t of p;
show t,p; showvariable x,y;
filldraw z0..{z4-z9}z4l--subpath (0,t) of (z4r{z9-z4}..z6r)
 --z2l---z1l..z1r---z2r--subpath (t,0) of (z3r{z9-z3}..z5r)
 --z3l{z9-z3}..z0 & cycle;	% arrowhead and stem
penlabels(0,1,2,3,4,5,6,9); endchar;