Graph updates; readme updates

1 files changed, 10 insertions, 42 deletions

diff --git a/chapter09/docs/09-graph6.svg b/chapter09/docs/09-graph6.svg
index 2d530c46..b573d88a 100644
--- a/chapter09/docs/09-graph6.svg
+++ b/chapter09/docs/09-graph6.svg
@@ -1,4 +1,4 @@
-<svg aria-label="Compiler graph" width="841" height="788" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 841 788" style="font-family: sans-serif;"><style>
+<svg aria-label="Compiler graph" width="350" height="360" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 350 360" style="font-family: sans-serif;"><style>
     html, body { height:100%; margin:0; font-family:sans-serif; }
     .viewer { height:100%; display:grid; grid-template-rows:auto minmax(0,1fr) auto; }
     .source { padding:8px; border-bottom:1px solid #ccc; }
@@ -60,60 +60,28 @@
     .count { font-size:20px; min-width:35px; text-align:center; }
     #N { width:6ch; }
     #scrub { width:clamp(120px,35vw,600px); }
-  </style><defs><marker id="arrow-CTRL" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#b63838"/></marker><marker id="arrow-DATA" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#536477"/></marker><marker id="arrow-MEM" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#2867b2"/></marker><marker id="arrow-ASSOC" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#9396a3"/></marker><marker id="arrow-PARSER" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#7956a5"/></marker></defs><rect width="100%" height="100%" fill="rgb(250, 251, 252)"/><g><g class="regions" style="opacity: 1;"><g class="region" transform="translate(24,171)"><rect class="region-box" rx="8" width="637" height="410" fill="#f1f6fc"/></g></g><rect class="peep-area" rx="36" style="opacity: 0;"/><g class="edges"><path class="edge CTRL" id="e3i0" d="M246,687 C246,711 420.5,714 420.5,738" stroke="#b63838" marker-start="url(#arrow-CTRL)" style="opacity: 1;"><title>#3[0] → #21 · CTRL</title></path><path class="edge CTRL" id="e7i1" d="M126,118 L126,241" stroke="#b63838" marker-start="url(#arrow-CTRL)" style="opacity: 1;"><title>#7[1] → #1 · CTRL</title></path><path class="edge CTRL" id="e7i2" d="M106,546 L106,556 L649,556 L649,224 L156,224 L156,244" stroke="#b63838" marker-start="url(#arrow-CTRL)" style="opacity: 1;"><title>#7[2] → #5 · CTRL</title></path><path class="edge DATA" id="e9i1" d="M246,118 L246,128 L258,128 L258,241" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#9[1] → #4 · DATA</title></path><path class="edge DATA" id="e9i2" d="M525,398 L525,408 L639,408 L639,232 L298,232 L298,244" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#9[2] → #25 · DATA</title></path><path class="edge DATA" id="e10i1" d="M278,297 L278,317 L373,317 L373,345" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#10[1] → #9 · DATA</title></path><path class="edge DATA" id="e10i2" d="M605,118 L605,307 L403,307 L403,345" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#10[2] → #11 · DATA</title></path><path class="edge CTRL" id="e12i0" d="M126,297 L126,449" stroke="#b63838" marker-start="url(#arrow-CTRL)" style="opacity: 1;"><title>#12[0] → #7 · CTRL</title></path><path class="edge DATA" id="e12i1" d="M373,401 L373,411 L206,411 L206,449" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#12[1] → #10 · DATA</title></path><path class="edge CTRL" id="e21i0" d="M226,549 L226,634" stroke="#b63838" marker-start="url(#arrow-CTRL)" style="opacity: 1;"><title>#21[0] → #6 · CTRL</title></path><path class="edge DATA" id="e21i1" d="M278,297 L278,317 L302,317 L302,596 L266,596 L266,634" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#21[1] → #9 · DATA</title></path><path class="edge DATA" id="e25i1" d="M278,297 L278,317 L525,317 L525,345" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#25[1] → #9 · DATA</title></path><path class="edge DATA" id="e25i2" d="M757,118 L757,128 L616,128 L616,317 L555,317 L555,345" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#25[2] → #24 · DATA</title></path></g><g class="edge-hits"/><g class="parser" style="opacity: 1;"/><g class="nodes"><g class="node" id="n1" data-id="1" transform="translate(66,68)" style="opacity: 1;"><path class="box" d="M0,0H120V44H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>$ctrl</tspan><tspan class="node-id">  #1/0</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#1 $ctrl
-Projection 0 of #2
+  </style><defs><marker id="arrow-CTRL" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#b63838"/></marker><marker id="arrow-DATA" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#536477"/></marker><marker id="arrow-MEM" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#2867b2"/></marker><marker id="arrow-ASSOC" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#9396a3"/></marker><marker id="arrow-PARSER" viewBox="0 -4 8 8" refX="8" refY="0" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0,-4L8,0L0,4Z" fill="#7956a5"/></marker></defs><rect width="100%" height="100%" fill="rgb(250, 251, 252)"/><g><g class="regions" style="opacity: 1;"/><rect class="peep-area" rx="36" style="opacity: 0;"/><g class="edges"><path class="edge DATA" id="e9i1" d="M84,118 L84,166" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#9[1] → #4 · DATA</title></path><path class="edge DATA" id="e9i2" d="M236,326 L236,331 Q236,336 241,336 L318,336 Q326,336 326,328 L326,136 Q326,128 318,128 L132,128 Q124,128 124,136 L124,166" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#9[2] → #25 · DATA</title></path><path class="edge DATA" id="e21i1" d="M104,222 L104,270" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#21[1] → #9 · DATA</title></path><path class="edge DATA" id="e25i1" d="M104,222 L104,227 Q104,232 109,232 L228,232 Q236,232 236,240 L236,270" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#25[1] → #9 · DATA</title></path><path class="edge DATA" id="e25i2" d="M256,222 L256,227 Q256,232 261,232 L261,232 Q266,232 266,237 L266,270" stroke="#536477" marker-start="url(#arrow-DATA)" style="opacity: 1;"><title>#25[2] → #24 · DATA</title></path></g><g class="edge-hits"/><g class="parser" style="opacity: 1;"/><g class="nodes"><g class="node" id="n2" data-id="2" transform="translate(24,24)" style="opacity: 1;"><path class="box" d="M0,0H120V44H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>Start</tspan><tspan class="node-id">  #2</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#2 Start
 Type not computed
 
-[0] → #2  CTRL</title></g><g class="node" id="n2" data-id="2" transform="translate(66,24)" style="opacity: 1;"><path class="box" d="M0,0H240V44H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="120" y="18"><tspan>Start</tspan><tspan class="node-id">  #2</tspan></text><text class="type" text-anchor="middle" y="35" x="120"/><title>#2 Start
-Type not computed
-
-</title></g><g class="node" id="n3" data-id="3" transform="translate(384.5,738)" style="opacity: 1;"><path class="box" d="M0,0H72V26H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="36" y="17"><tspan>Stop</tspan><tspan class="node-id">  #3</tspan></text><text class="type" text-anchor="middle" y="35" x="36"/><title>#3 Stop
-Type not computed
-
-[0] → #21  CTRL</title><circle class="port" cx="36" cy="0" r="3" fill="#536477"/><text class="slot" x="36" y="-7" text-anchor="middle">0</text></g><g class="node" id="n4" data-id="4" transform="translate(186,68)" style="opacity: 1;"><path class="box" d="M0,0H120V44H0Z" fill="#edf3f7"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>arg</tspan><tspan class="node-id">  #4/1</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#4 arg
+</title></g><g class="node" id="n4" data-id="4" transform="translate(24,68)" style="opacity: 1;"><path class="box" d="M0,0H120V44H0Z" fill="#edf3f7"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>arg</tspan><tspan class="node-id">  #4/1</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#4 arg
 Projection 1 of #2
 Type not computed
 
-[0] → #2  DATA</title></g><g class="node" id="n5" data-id="5" transform="translate(46,499)" style="opacity: 1;"><path class="box" d="M0,0H120V44H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>True</tspan><tspan class="node-id">  #5/0</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#5 True
-Projection 0 of #12
-Type not computed
-
-[0] → #12  CTRL</title></g><g class="node" id="n6" data-id="6" transform="translate(166,499)" style="opacity: 1;"><path class="box" d="M0,0H120V44H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>False</tspan><tspan class="node-id">  #6/1</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#6 False
-Projection 1 of #12
-Type not computed
-
-[0] → #12  CTRL</title></g><g class="node" id="n7" data-id="7" transform="translate(66,247)" style="opacity: 1;"><path class="box" d="M20,0H100Q120,0 120,20V24Q120,44 100,44H20Q0,44 0,24V20Q0,0 20,0Z" fill="#ffe0ab"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>Loop</tspan><tspan class="node-id">  #7</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#7 Loop
+[0] → #2  DATA</title></g><g class="node" id="n9" data-id="9" transform="translate(44,172)" style="opacity: 1;"><path class="box" d="M12,0H108L120,22L108,44H12L0,22Z" fill="#f5e4fa"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>φ_arg</tspan><tspan class="node-id">  #9</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#9 φ_arg
 Type not computed
 
-[0] → —  DATA
-[1] → #1  CTRL
-[2] → #5  CTRL</title><circle class="port" cx="30" cy="-3" r="3" fill="white"/><circle class="port" cx="60" cy="-3" r="3" fill="#536477"/><circle class="port" cx="90" cy="-3" r="3" fill="#536477"/><text class="slot" x="30" y="-10" text-anchor="middle">0</text><text class="slot" x="60" y="-10" text-anchor="middle">1</text><text class="slot" x="90" y="-10" text-anchor="middle">2</text></g><g class="node" id="n9" data-id="9" transform="translate(218,247)" style="opacity: 1;"><path class="box" d="M12,0H108L120,22L108,44H12L0,22Z" fill="#f5e4fa"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>φ_arg</tspan><tspan class="node-id">  #9</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#9 φ_arg
-Type not computed
-
-[0] → #7  ASSOC
+[0] → —  ASSOC
 [1] → #4  DATA
-[2] → #25  DATA</title><circle class="port" cx="-3" cy="22" r="3" fill="#536477"/><circle class="port" cx="40" cy="-3" r="3" fill="#536477"/><circle class="port" cx="80" cy="-3" r="3" fill="#536477"/><path class="reg" fill="none" stroke="#b63838" d="M-3,22H-18m4,-3l-4,3l4,3"><title>[0] → #7</title></path><text class="slot" x="-10" y="15" text-anchor="middle">0</text><text class="slot" x="40" y="-10" text-anchor="middle">1</text><text class="slot" x="80" y="-10" text-anchor="middle">2</text></g><g class="node" id="n10" data-id="10" transform="translate(313,351)" style="opacity: 1;"><path class="box" d="M14,0H106Q120,0 120,14V30Q120,44 106,44H14Q0,44 0,30V14Q0,0 14,0Z" fill="#edf3f7"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>&lt;</tspan><tspan class="node-id">  #10</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#10 &lt;
-Type not computed
-
-[0] → —  DATA
-[1] → #9  DATA
-[2] → #11  DATA</title><circle class="port" cx="30" cy="-3" r="3" fill="white"/><circle class="port" cx="60" cy="-3" r="3" fill="#536477"/><circle class="port" cx="90" cy="-3" r="3" fill="#536477"/><text class="slot" x="30" y="-10" text-anchor="middle">0</text><text class="slot" x="60" y="-10" text-anchor="middle">1</text><text class="slot" x="90" y="-10" text-anchor="middle">2</text></g><g class="node" id="n11" data-id="11" transform="translate(545,68)" style="opacity: 1;"><path class="box" d="M14,0H106Q120,0 120,14V30Q120,44 106,44H14Q0,44 0,30V14Q0,0 14,0Z" fill="#edf3f7"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>#10</tspan><tspan class="node-id">  #11</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#11 #10
-Type not computed
-
-</title></g><g class="node" id="n12" data-id="12" transform="translate(46,455)" style="opacity: 1;"><path class="box" d="M0,0H240V44H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="120" y="18"><tspan>If</tspan><tspan class="node-id">  #12</tspan></text><text class="type" text-anchor="middle" y="35" x="120"/><title>#12 If
-Type not computed
-
-[0] → #7  CTRL
-[1] → #10  DATA</title><circle class="port" cx="80" cy="-3" r="3" fill="#536477"/><circle class="port" cx="160" cy="-3" r="3" fill="#536477"/><text class="slot" x="80" y="-10" text-anchor="middle">0</text><text class="slot" x="160" y="-10" text-anchor="middle">1</text></g><g class="node" id="n21" data-id="21" transform="translate(186,640)" style="opacity: 1;"><path class="box" d="M0,0H120V44H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>Return</tspan><tspan class="node-id">  #21</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#21 Return
+[2] → #25  DATA</title><circle class="port" cx="0" cy="-3" r="3" fill="white"/><circle class="port" cx="40" cy="-3" r="3" fill="#536477"/><circle class="port" cx="80" cy="-3" r="3" fill="#536477"/><text class="slot" x="0" y="-10" text-anchor="middle">0</text><text class="slot" x="40" y="-10" text-anchor="middle">1</text><text class="slot" x="80" y="-10" text-anchor="middle">2</text></g><g class="node" id="n21" data-id="21" transform="translate(24,276)" style="opacity: 1;"><path class="box" d="M0,0H120V44H0Z" fill="#fff1c4"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>Return</tspan><tspan class="node-id">  #21</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#21 Return
 Type not computed
 
-[0] → #6  CTRL
-[1] → #9  DATA</title><circle class="port" cx="40" cy="-3" r="3" fill="#536477"/><circle class="port" cx="80" cy="-3" r="3" fill="#536477"/><text class="slot" x="40" y="-10" text-anchor="middle">0</text><text class="slot" x="80" y="-10" text-anchor="middle">1</text></g><g class="node" id="n24" data-id="24" transform="translate(697,68)" style="opacity: 1;"><path class="box" d="M14,0H106Q120,0 120,14V30Q120,44 106,44H14Q0,44 0,30V14Q0,0 14,0Z" fill="#edf3f7"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>#2</tspan><tspan class="node-id">  #24</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#24 #2
+[0] → —  CTRL
+[1] → #9  DATA</title><circle class="port" cx="40" cy="-3" r="3" fill="white"/><circle class="port" cx="80" cy="-3" r="3" fill="#536477"/><text class="slot" x="40" y="-10" text-anchor="middle">0</text><text class="slot" x="80" y="-10" text-anchor="middle">1</text></g><g class="node" id="n24" data-id="24" transform="translate(196,172)" style="opacity: 1;"><path class="box" d="M14,0H106Q120,0 120,14V30Q120,44 106,44H14Q0,44 0,30V14Q0,0 14,0Z" fill="#edf3f7"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>#2</tspan><tspan class="node-id">  #24</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#24 #2
 Type not computed
 
-</title></g><g class="node" id="n25" data-id="25" transform="translate(465,351)" style="opacity: 1;"><path class="box" d="M14,0H106Q120,0 120,14V30Q120,44 106,44H14Q0,44 0,30V14Q0,0 14,0Z" fill="#edf3f7"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>+</tspan><tspan class="node-id">  #25</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#25 +
+</title></g><g class="node" id="n25" data-id="25" transform="translate(176,276)" style="opacity: 1;"><path class="box" d="M14,0H106Q120,0 120,14V30Q120,44 106,44H14Q0,44 0,30V14Q0,0 14,0Z" fill="#edf3f7"/><text class="label" text-anchor="middle" x="60" y="18"><tspan>+</tspan><tspan class="node-id">  #25</tspan></text><text class="type" text-anchor="middle" y="35" x="60"/><title>#25 +
 Type not computed
 
 [0] → —  DATA
 [1] → #9  DATA
-[2] → #24  DATA</title><circle class="port" cx="30" cy="-3" r="3" fill="white"/><circle class="port" cx="60" cy="-3" r="3" fill="#536477"/><circle class="port" cx="90" cy="-3" r="3" fill="#536477"/><text class="slot" x="30" y="-10" text-anchor="middle">0</text><text class="slot" x="60" y="-10" text-anchor="middle">1</text><text class="slot" x="90" y="-10" text-anchor="middle">2</text></g></g><g class="region-heads" style="opacity: 1;"><g class="region-head" transform="translate(24,171)"><text class="label" x="26" y="17"><tspan>Loop</tspan><tspan class="node-id">  #7</tspan></text><title>Loop · 7 nodes</title><g class="fold-btn" role="button" tabindex="0" transform="translate(4,4)" aria-label="Fold region #7"><rect width="16" height="16" rx="2"/><text x="8" y="12" text-anchor="middle">−</text><title>Fold region</title></g></g></g><g class="shortcuts" style="opacity: 1;"/><g class="peep-ghosts" pointer-events="none"/></g></svg>
+[2] → #24  DATA</title><circle class="port" cx="30" cy="-3" r="3" fill="white"/><circle class="port" cx="60" cy="-3" r="3" fill="#536477"/><circle class="port" cx="90" cy="-3" r="3" fill="#536477"/><text class="slot" x="30" y="-10" text-anchor="middle">0</text><text class="slot" x="60" y="-10" text-anchor="middle">1</text><text class="slot" x="90" y="-10" text-anchor="middle">2</text></g></g><g class="region-heads" style="opacity: 1;"/><g class="shortcuts" style="opacity: 1;"/><g class="peep-ghosts" pointer-events="none"/></g></svg>