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authorKartik K. Agaram <vc@akkartik.com>2018-01-25 22:39:31 -0800
committerKartik K. Agaram <vc@akkartik.com>2018-01-25 22:39:31 -0800
commit805d58c6aeeeba3e4989c0eed6781b3861e8fae0 (patch)
treeea5225bdd7c5fbeea912671cdc5f1c4b2b2828d7 /html/chessboard.mu.html
parentaefa8fec6a473be459a2ff33e6bd96e7c22ced20 (diff)
downloadmu-805d58c6aeeeba3e4989c0eed6781b3861e8fae0.tar.gz
4199
Diffstat (limited to 'html/chessboard.mu.html')
-rw-r--r--html/chessboard.mu.html585
1 files changed, 292 insertions, 293 deletions
diff --git a/html/chessboard.mu.html b/html/chessboard.mu.html
index 7bc3a098..9bad77b0 100644
--- a/html/chessboard.mu.html
+++ b/html/chessboard.mu.html
@@ -15,19 +15,18 @@ body { font-size: 12pt; font-family: monospace; color: #aaaaaa; background-color
 a { color:#eeeeee; text-decoration: none; }
 a:hover { text-decoration: underline; }
 * { font-size: 12pt; font-size: 1em; }
+.muControl { color: #c0a020; }
+.muRecipe { color: #ff8700; }
 .muScenario { color: #00af00; }
-.Conceal { color: #4e4e4e; }
-.CommentedCode { color: #6c6c6c; }
 .LineNr { color: #444444; }
 .Delimiter { color: #800080; }
+.CommentedCode { color: #6c6c6c; }
+.Constant { color: #00a0a0; }
+.Special { color: #c00000; }
 .muData { color: #ffff00; }
-.SalientComment { color: #00ffff; }
 .Comment { color: #9090ff; }
 .Comment a { color:#0000ee; text-decoration:underline; }
-.Constant { color: #00a0a0; }
-.Special { color: #c00000; }
-.muControl { color: #c0a020; }
-.muRecipe { color: #ff8700; }
+.SalientComment { color: #00ffff; }
 -->
 </style>
 
@@ -65,10 +64,10 @@ if ('onhashchange' in window) {
 <span id="L1" class="LineNr">  1 </span><span class="Comment"># Chessboard program: you type in moves in algebraic notation, and it'll</span>
 <span id="L2" class="LineNr">  2 </span><span class="Comment"># display the position after each move.</span>
 <span id="L3" class="LineNr">  3 </span>
-<span id="L4" class="LineNr">  4 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L4'>main</a> [
+<span id="L4" class="LineNr">  4 </span><span class="muRecipe">def</span> main [
 <span id="L5" class="LineNr">  5 </span>  <span class="Constant">local-scope</span>
 <span id="L6" class="LineNr">  6 </span>  open-console  <span class="Comment"># take control of screen, keyboard and mouse</span>
-<span id="L7" class="LineNr">  7 </span>  <a href='081print.mu.html#L46'>clear-screen</a> <span class="Constant">0/screen</span>  <span class="Comment"># non-scrolling app</span>
+<span id="L7" class="LineNr">  7 </span>  clear-screen <span class="Constant">0/screen</span>  <span class="Comment"># non-scrolling app</span>
 <span id="L8" class="LineNr">  8 </span>
 <span id="L9" class="LineNr">  9 </span>  <span class="Comment"># The chessboard function takes keyboard and screen objects as inputs.</span>
 <span id="L10" class="LineNr"> 10 </span>  <span class="Comment">#</span>
@@ -77,7 +76,7 @@ if ('onhashchange' in window) {
 <span id="L13" class="LineNr"> 13 </span>  <span class="Comment">#</span>
 <span id="L14" class="LineNr"> 14 </span>  <span class="Comment"># Here the console and screen are both 0, which usually indicates real</span>
 <span id="L15" class="LineNr"> 15 </span>  <span class="Comment"># hardware rather than a fake for testing as you'll see below.</span>
-<span id="L16" class="LineNr"> 16 </span>  <a href='chessboard.mu.html#L69'>chessboard</a> <span class="Constant">0/screen</span>, <span class="Constant">0/console</span>
+<span id="L16" class="LineNr"> 16 </span>  chessboard <span class="Constant">0/screen</span>, <span class="Constant">0/console</span>
 <span id="L17" class="LineNr"> 17 </span>
 <span id="L18" class="LineNr"> 18 </span>  close-console  <span class="Comment"># clean up screen, keyboard and mouse</span>
 <span id="L19" class="LineNr"> 19 </span>]
@@ -91,84 +90,84 @@ if ('onhashchange' in window) {
 <span id="L27" class="LineNr"> 27 </span>  assume-screen <span class="Constant">120/width</span>, <span class="Constant">20/height</span>
 <span id="L28" class="LineNr"> 28 </span>  <span class="Comment"># initialize keyboard to type in a move</span>
 <span id="L29" class="LineNr"> 29 </span>  assume-console [
-<span id="L30" class="LineNr"> 30 </span>  <span class="Conceal">¦</span> type <span class="Constant">[a2-a4</span>
+<span id="L30" class="LineNr"> 30 </span>    type <span class="Constant">[a2-a4</span>
 <span id="L31" class="LineNr"> 31 </span><span class="Constant">]</span>
 <span id="L32" class="LineNr"> 32 </span>  ]
 <span id="L33" class="LineNr"> 33 </span>  run [
-<span id="L34" class="LineNr"> 34 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L16'>screen</a>, <a href='084console.mu.html#L23'>console</a> <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L69'>chessboard</a> <a href='081print.mu.html#L16'>screen</a>, <a href='084console.mu.html#L23'>console</a>
-<span id="L35" class="LineNr"> 35 </span>  <span class="Conceal">¦</span> <span class="Comment"># icon for the cursor</span>
-<span id="L36" class="LineNr"> 36 </span>  <span class="Conceal">¦</span> cursor-icon:char <span class="Special">&lt;-</span> copy <span class="Constant">9251/␣</span>
-<span id="L37" class="LineNr"> 37 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L16'>screen</a> <span class="Special">&lt;-</span> print <a href='081print.mu.html#L16'>screen</a>, cursor-icon
+<span id="L34" class="LineNr"> 34 </span>    screen, console <span class="Special">&lt;-</span> chessboard screen, console
+<span id="L35" class="LineNr"> 35 </span>    <span class="Comment"># icon for the cursor</span>
+<span id="L36" class="LineNr"> 36 </span>    cursor-icon:char <span class="Special">&lt;-</span> copy <span class="Constant">9251/␣</span>
+<span id="L37" class="LineNr"> 37 </span>    screen <span class="Special">&lt;-</span> print screen, cursor-icon
 <span id="L38" class="LineNr"> 38 </span>  ]
 <span id="L39" class="LineNr"> 39 </span>  screen-should-contain [
 <span id="L40" class="LineNr"> 40 </span>  <span class="Comment">#            1         2         3         4         5         6         7         8         9         10        11</span>
 <span id="L41" class="LineNr"> 41 </span>  <span class="Comment">#  012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789</span>
-<span id="L42" class="LineNr"> 42 </span>  <span class="Conceal">¦</span><span class="Constant"> .Stupid text-mode chessboard. White pieces in uppercase; black pieces in lowercase. No checking for legal moves.         .</span>
-<span id="L43" class="LineNr"> 43 </span>  <span class="Conceal">¦</span><span class="Constant"> .                                                                                                                        .</span>
-<span id="L44" class="LineNr"> 44 </span>  <span class="Conceal">¦</span><span class="Constant"> .8 | r n b q k b n r                                                                                                     .</span>
-<span id="L45" class="LineNr"> 45 </span>  <span class="Conceal">¦</span><span class="Constant"> .7 | p p p p p p p p                                                                                                     .</span>
-<span id="L46" class="LineNr"> 46 </span>  <span class="Conceal">¦</span><span class="Constant"> .6 |                                                                                                                     .</span>
-<span id="L47" class="LineNr"> 47 </span>  <span class="Conceal">¦</span><span class="Constant"> .5 |                                                                                                                     .</span>
-<span id="L48" class="LineNr"> 48 </span>  <span class="Conceal">¦</span><span class="Constant"> .4 | P                                                                                                                   .</span>
-<span id="L49" class="LineNr"> 49 </span>  <span class="Conceal">¦</span><span class="Constant"> .3 |                                                                                                                     .</span>
-<span id="L50" class="LineNr"> 50 </span>  <span class="Conceal">¦</span><span class="Constant"> .2 |   P P P P P P P                                                                                                     .</span>
-<span id="L51" class="LineNr"> 51 </span>  <span class="Conceal">¦</span><span class="Constant"> .1 | R N B Q K B N R                                                                                                     .</span>
-<span id="L52" class="LineNr"> 52 </span>  <span class="Conceal">¦</span><span class="Constant"> .  +----------------                                                                                                     .</span>
-<span id="L53" class="LineNr"> 53 </span>  <span class="Conceal">¦</span><span class="Constant"> .    a b c d e f g h                                                                                                     .</span>
-<span id="L54" class="LineNr"> 54 </span>  <span class="Conceal">¦</span><span class="Constant"> .                                                                                                                        .</span>
-<span id="L55" class="LineNr"> 55 </span>  <span class="Conceal">¦</span><span class="Constant"> .Type in your <a href='chessboard.mu.html#L239'>move</a> as &lt;from square&gt;-&lt;to square&gt;. For example: 'a2-a4'. Then press &lt;enter&gt;.                               .</span>
-<span id="L56" class="LineNr"> 56 </span>  <span class="Conceal">¦</span><span class="Constant"> .                                                                                                                        .</span>
-<span id="L57" class="LineNr"> 57 </span>  <span class="Conceal">¦</span><span class="Constant"> .Hit 'q' to exit.                                                                                                        .</span>
-<span id="L58" class="LineNr"> 58 </span>  <span class="Conceal">¦</span><span class="Constant"> .                                                                                                                        .</span>
-<span id="L59" class="LineNr"> 59 </span>  <span class="Conceal">¦</span><span class="Constant"> .move: ␣                                                                                                                 .</span>
-<span id="L60" class="LineNr"> 60 </span>  <span class="Conceal">¦</span><span class="Constant"> .                                                                                                                        .</span>
-<span id="L61" class="LineNr"> 61 </span>  <span class="Conceal">¦</span><span class="Constant"> .                                                                                                                        .</span>
+<span id="L42" class="LineNr"> 42 </span>   <span class="Constant"> .Stupid text-mode chessboard. White pieces in uppercase; black pieces in lowercase. No checking for legal moves.         .</span>
+<span id="L43" class="LineNr"> 43 </span>   <span class="Constant"> .                                                                                                                        .</span>
+<span id="L44" class="LineNr"> 44 </span>   <span class="Constant"> .8 | r n b q k b n r                                                                                                     .</span>
+<span id="L45" class="LineNr"> 45 </span>   <span class="Constant"> .7 | p p p p p p p p                                                                                                     .</span>
+<span id="L46" class="LineNr"> 46 </span>   <span class="Constant"> .6 |                                                                                                                     .</span>
+<span id="L47" class="LineNr"> 47 </span>   <span class="Constant"> .5 |                                                                                                                     .</span>
+<span id="L48" class="LineNr"> 48 </span>   <span class="Constant"> .4 | P                                                                                                                   .</span>
+<span id="L49" class="LineNr"> 49 </span>   <span class="Constant"> .3 |                                                                                                                     .</span>
+<span id="L50" class="LineNr"> 50 </span>   <span class="Constant"> .2 |   P P P P P P P                                                                                                     .</span>
+<span id="L51" class="LineNr"> 51 </span>   <span class="Constant"> .1 | R N B Q K B N R                                                                                                     .</span>
+<span id="L52" class="LineNr"> 52 </span>   <span class="Constant"> .  +----------------                                                                                                     .</span>
+<span id="L53" class="LineNr"> 53 </span>   <span class="Constant"> .    a b c d e f g h                                                                                                     .</span>
+<span id="L54" class="LineNr"> 54 </span>   <span class="Constant"> .                                                                                                                        .</span>
+<span id="L55" class="LineNr"> 55 </span>   <span class="Constant"> .Type in your move as &lt;from square&gt;-&lt;to square&gt;. For example: 'a2-a4'. Then press &lt;enter&gt;.                               .</span>
+<span id="L56" class="LineNr"> 56 </span>   <span class="Constant"> .                                                                                                                        .</span>
+<span id="L57" class="LineNr"> 57 </span>   <span class="Constant"> .Hit 'q' to exit.                                                                                                        .</span>
+<span id="L58" class="LineNr"> 58 </span>   <span class="Constant"> .                                                                                                                        .</span>
+<span id="L59" class="LineNr"> 59 </span>   <span class="Constant"> .move: ␣                                                                                                                 .</span>
+<span id="L60" class="LineNr"> 60 </span>   <span class="Constant"> .                                                                                                                        .</span>
+<span id="L61" class="LineNr"> 61 </span>   <span class="Constant"> .                                                                                                                        .</span>
 <span id="L62" class="LineNr"> 62 </span>  ]
 <span id="L63" class="LineNr"> 63 </span>]
 <span id="L64" class="LineNr"> 64 </span>
 <span id="L65" class="LineNr"> 65 </span><span class="SalientComment">## Here's how 'chessboard' is implemented.</span>
 <span id="L66" class="LineNr"> 66 </span>
-<span id="L67" class="LineNr"> 67 </span><span class="muData">type</span> <a href='chessboard.mu.html#L67'>board</a> = &amp;:@:&amp;:@:char  <span class="Comment"># a 2-D array of arrays of characters</span>
+<span id="L67" class="LineNr"> 67 </span><span class="muData">type</span> board = &amp;:@:&amp;:@:char  <span class="Comment"># a 2-D array of arrays of characters</span>
 <span id="L68" class="LineNr"> 68 </span>
-<span id="L69" class="LineNr"> 69 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L69'>chessboard</a> <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a>, <a href='084console.mu.html#L23'>console</a>:&amp;:<a href='084console.mu.html#L23'>console</a><span class="muRecipe"> -&gt; </span><a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a>, <a href='084console.mu.html#L23'>console</a>:&amp;:<a href='084console.mu.html#L23'>console</a> [
+<span id="L69" class="LineNr"> 69 </span><span class="muRecipe">def</span> chessboard screen:&amp;:screen, console:&amp;:console<span class="muRecipe"> -&gt; </span>screen:&amp;:screen, console:&amp;:console [
 <span id="L70" class="LineNr"> 70 </span>  <span class="Constant">local-scope</span>
 <span id="L71" class="LineNr"> 71 </span>  <span class="Constant">load-inputs</span>
-<span id="L72" class="LineNr"> 72 </span>  <a href='chessboard.mu.html#L67'>board</a>:<a href='chessboard.mu.html#L67'>board</a> <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L190'>initial-position</a>
+<span id="L72" class="LineNr"> 72 </span>  board:board <span class="Special">&lt;-</span> initial-position
 <span id="L73" class="LineNr"> 73 </span>  <span class="Comment"># hook up stdin</span>
-<span id="L74" class="LineNr"> 74 </span>  stdin-in:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, stdin-out:&amp;:<a href='075channel.mu.html#L47'>sink</a>:char <span class="Special">&lt;-</span> <a href='075channel.mu.html#L51'>new-channel</a> <span class="Constant">10/capacity</span>
-<span id="L75" class="LineNr"> 75 </span>  <span class="muControl">start-running</span> <a href='084console.mu.html#L73'>send-keys-to-channel</a>, <a href='084console.mu.html#L23'>console</a>, stdin-out, <a href='081print.mu.html#L16'>screen</a>
+<span id="L74" class="LineNr"> 74 </span>  stdin-in:&amp;:source:char, stdin-out:&amp;:sink:char <span class="Special">&lt;-</span> new-channel <span class="Constant">10/capacity</span>
+<span id="L75" class="LineNr"> 75 </span>  <span class="muControl">start-running</span> send-keys-to-channel, console, stdin-out, screen
 <span id="L76" class="LineNr"> 76 </span>  <span class="Comment"># buffer lines in stdin</span>
-<span id="L77" class="LineNr"> 77 </span>  buffered-stdin-in:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, buffered-stdin-out:&amp;:<a href='075channel.mu.html#L47'>sink</a>:char <span class="Special">&lt;-</span> <a href='075channel.mu.html#L51'>new-channel</a> <span class="Constant">10/capacity</span>
-<span id="L78" class="LineNr"> 78 </span>  <span class="muControl">start-running</span> <a href='075channel.mu.html#L408'>buffer-lines</a>, stdin-in, buffered-stdin-out
+<span id="L77" class="LineNr"> 77 </span>  buffered-stdin-in:&amp;:source:char, buffered-stdin-out:&amp;:sink:char <span class="Special">&lt;-</span> new-channel <span class="Constant">10/capacity</span>
+<span id="L78" class="LineNr"> 78 </span>  <span class="muControl">start-running</span> buffer-lines, stdin-in, buffered-stdin-out
 <span id="L79" class="LineNr"> 79 </span>  <span class="Delimiter">{</span>
-<span id="L80" class="LineNr"> 80 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[Stupid text-mode chessboard. White pieces in uppercase; black pieces in lowercase. No checking for legal moves.</span>
+<span id="L80" class="LineNr"> 80 </span>    print screen, <span class="Constant">[Stupid text-mode chessboard. White pieces in uppercase; black pieces in lowercase. No checking for legal moves.</span>
 <span id="L81" class="LineNr"> 81 </span><span class="Constant">]</span>
-<span id="L82" class="LineNr"> 82 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L752'>cursor-to-next-line</a> <a href='081print.mu.html#L16'>screen</a>
-<span id="L83" class="LineNr"> 83 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <a href='chessboard.mu.html#L67'>board</a>
-<span id="L84" class="LineNr"> 84 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L752'>cursor-to-next-line</a> <a href='081print.mu.html#L16'>screen</a>
-<span id="L85" class="LineNr"> 85 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[Type in your <a href='chessboard.mu.html#L239'>move</a> as &lt;from square&gt;-&lt;to square&gt;. For example: 'a2-a4'. Then press &lt;enter&gt;.</span>
+<span id="L82" class="LineNr"> 82 </span>    cursor-to-next-line screen
+<span id="L83" class="LineNr"> 83 </span>    print screen, board
+<span id="L84" class="LineNr"> 84 </span>    cursor-to-next-line screen
+<span id="L85" class="LineNr"> 85 </span>    print screen, <span class="Constant">[Type in your move as &lt;from square&gt;-&lt;to square&gt;. For example: 'a2-a4'. Then press &lt;enter&gt;.</span>
 <span id="L86" class="LineNr"> 86 </span><span class="Constant">]</span>
-<span id="L87" class="LineNr"> 87 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L752'>cursor-to-next-line</a> <a href='081print.mu.html#L16'>screen</a>
-<span id="L88" class="LineNr"> 88 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a> <span class="Constant">[Hit 'q' to exit.</span>
+<span id="L87" class="LineNr"> 87 </span>    cursor-to-next-line screen
+<span id="L88" class="LineNr"> 88 </span>    print screen <span class="Constant">[Hit 'q' to exit.</span>
 <span id="L89" class="LineNr"> 89 </span><span class="Constant">]</span>
-<span id="L90" class="LineNr"> 90 </span>  <span class="Conceal">¦</span> <span class="Delimiter">{</span>
-<span id="L91" class="LineNr"> 91 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> <a href='081print.mu.html#L752'>cursor-to-next-line</a> <a href='081print.mu.html#L16'>screen</a>
-<span id="L92" class="LineNr"> 92 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> <a href='081print.mu.html#L16'>screen</a> <span class="Special">&lt;-</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[move: ]</span>
-<span id="L93" class="LineNr"> 93 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> m:&amp;:<a href='chessboard.mu.html#L239'>move</a>, quit:bool, error:bool <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L248'>read-move</a> buffered-stdin-in, <a href='081print.mu.html#L16'>screen</a>
-<span id="L94" class="LineNr"> 94 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> <span class="muControl">break-if</span> quit, <span class="Constant">+quit</span>
-<span id="L95" class="LineNr"> 95 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> buffered-stdin-in <span class="Special">&lt;-</span> <a href='075channel.mu.html#L312'>clear</a> buffered-stdin-in  <span class="Comment"># cleanup after error. todo: test this?</span>
-<span id="L96" class="LineNr"> 96 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> <span class="muControl">loop-if</span> error
-<span id="L97" class="LineNr"> 97 </span>  <span class="Conceal">¦</span> <span class="Delimiter">}</span>
-<span id="L98" class="LineNr"> 98 </span>  <span class="Conceal">¦</span> <a href='chessboard.mu.html#L67'>board</a> <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L534'>make-move</a> <a href='chessboard.mu.html#L67'>board</a>, m
-<span id="L99" class="LineNr"> 99 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L16'>screen</a> <span class="Special">&lt;-</span> <a href='081print.mu.html#L46'>clear-screen</a> <a href='081print.mu.html#L16'>screen</a>
-<span id="L100" class="LineNr">100 </span>  <span class="Conceal">¦</span><span class="muControl"> loop</span>
+<span id="L90" class="LineNr"> 90 </span>    <span class="Delimiter">{</span>
+<span id="L91" class="LineNr"> 91 </span>      cursor-to-next-line screen
+<span id="L92" class="LineNr"> 92 </span>      screen <span class="Special">&lt;-</span> print screen, <span class="Constant">[move: ]</span>
+<span id="L93" class="LineNr"> 93 </span>      m:&amp;:move, quit:bool, error:bool <span class="Special">&lt;-</span> read-move buffered-stdin-in, screen
+<span id="L94" class="LineNr"> 94 </span>      <span class="muControl">break-if</span> quit, <span class="Constant">+quit</span>
+<span id="L95" class="LineNr"> 95 </span>      buffered-stdin-in <span class="Special">&lt;-</span> clear buffered-stdin-in  <span class="Comment"># cleanup after error. todo: test this?</span>
+<span id="L96" class="LineNr"> 96 </span>      <span class="muControl">loop-if</span> error
+<span id="L97" class="LineNr"> 97 </span>    <span class="Delimiter">}</span>
+<span id="L98" class="LineNr"> 98 </span>    board <span class="Special">&lt;-</span> make-move board, m
+<span id="L99" class="LineNr"> 99 </span>    screen <span class="Special">&lt;-</span> clear-screen screen
+<span id="L100" class="LineNr">100 </span>   <span class="muControl"> loop</span>
 <span id="L101" class="LineNr">101 </span>  <span class="Delimiter">}</span>
 <span id="L102" class="LineNr">102 </span><span class="Constant">  +quit</span>
 <span id="L103" class="LineNr">103 </span>]
 <span id="L104" class="LineNr">104 </span>
 <span id="L105" class="LineNr">105 </span><span class="SalientComment">## a board is an array of files, a file is an array of characters (squares)</span>
 <span id="L106" class="LineNr">106 </span>
-<span id="L107" class="LineNr">107 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L107'>new-board</a> <a href='chessboard.mu.html#L190'>initial-position</a>:&amp;:@:char<span class="muRecipe"> -&gt; </span><a href='chessboard.mu.html#L67'>board</a>:<a href='chessboard.mu.html#L67'>board</a> [
+<span id="L107" class="LineNr">107 </span><span class="muRecipe">def</span> new-board initial-position:&amp;:@:char<span class="muRecipe"> -&gt; </span>board:board [
 <span id="L108" class="LineNr">108 </span>  <span class="Constant">local-scope</span>
 <span id="L109" class="LineNr">109 </span>  <span class="Constant">load-inputs</span>
 <span id="L110" class="LineNr">110 </span>  <span class="Comment"># assert(length(initial-position) == 64)</span>
@@ -176,73 +175,73 @@ if ('onhashchange' in window) {
 <span id="L112" class="LineNr">112 </span>  correct-length?:bool <span class="Special">&lt;-</span> equal len,<span class="Constant"> 64</span>
 <span id="L113" class="LineNr">113 </span>  assert correct-length?, <span class="Constant">[chessboard had incorrect size]</span>
 <span id="L114" class="LineNr">114 </span>  <span class="Comment"># board is an array of pointers to files; file is an array of characters</span>
-<span id="L115" class="LineNr">115 </span>  <a href='chessboard.mu.html#L67'>board</a> <span class="Special">&lt;-</span> new <span class="Delimiter">{</span>(address array character): type<span class="Delimiter">}</span>,<span class="Constant"> 8</span>
+<span id="L115" class="LineNr">115 </span>  board <span class="Special">&lt;-</span> new <span class="Delimiter">{</span>(address array character): type<span class="Delimiter">}</span>,<span class="Constant"> 8</span>
 <span id="L116" class="LineNr">116 </span>  col:num <span class="Special">&lt;-</span> copy<span class="Constant"> 0</span>
 <span id="L117" class="LineNr">117 </span>  <span class="Delimiter">{</span>
-<span id="L118" class="LineNr">118 </span>  <span class="Conceal">¦</span> done?:bool <span class="Special">&lt;-</span> equal col,<span class="Constant"> 8</span>
-<span id="L119" class="LineNr">119 </span>  <span class="Conceal">¦</span> <span class="muControl">break-if</span> done?
-<span id="L120" class="LineNr">120 </span>  <span class="Conceal">¦</span> file:&amp;:@:char <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L127'>new-file</a> <a href='chessboard.mu.html#L190'>initial-position</a>, col
-<span id="L121" class="LineNr">121 </span>  <span class="Conceal">¦</span> *board <span class="Special">&lt;-</span> put-index *board, col, file
-<span id="L122" class="LineNr">122 </span>  <span class="Conceal">¦</span> col <span class="Special">&lt;-</span> add col,<span class="Constant"> 1</span>
-<span id="L123" class="LineNr">123 </span>  <span class="Conceal">¦</span><span class="muControl"> loop</span>
+<span id="L118" class="LineNr">118 </span>    done?:bool <span class="Special">&lt;-</span> equal col,<span class="Constant"> 8</span>
+<span id="L119" class="LineNr">119 </span>    <span class="muControl">break-if</span> done?
+<span id="L120" class="LineNr">120 </span>    file:&amp;:@:char <span class="Special">&lt;-</span> new-file initial-position, col
+<span id="L121" class="LineNr">121 </span>    *board <span class="Special">&lt;-</span> put-index *board, col, file
+<span id="L122" class="LineNr">122 </span>    col <span class="Special">&lt;-</span> add col,<span class="Constant"> 1</span>
+<span id="L123" class="LineNr">123 </span>   <span class="muControl"> loop</span>
 <span id="L124" class="LineNr">124 </span>  <span class="Delimiter">}</span>
 <span id="L125" class="LineNr">125 </span>]
 <span id="L126" class="LineNr">126 </span>
-<span id="L127" class="LineNr">127 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L127'>new-file</a> position:&amp;:@:char, index:num<span class="muRecipe"> -&gt; </span>result:&amp;:@:char [
+<span id="L127" class="LineNr">127 </span><span class="muRecipe">def</span> new-file position:&amp;:@:char, index:num<span class="muRecipe"> -&gt; </span>result:&amp;:@:char [
 <span id="L128" class="LineNr">128 </span>  <span class="Constant">local-scope</span>
 <span id="L129" class="LineNr">129 </span>  <span class="Constant">load-inputs</span>
 <span id="L130" class="LineNr">130 </span>  index <span class="Special">&lt;-</span> multiply index,<span class="Constant"> 8</span>
 <span id="L131" class="LineNr">131 </span>  result <span class="Special">&lt;-</span> new <span class="Constant">character:type</span>,<span class="Constant"> 8</span>
 <span id="L132" class="LineNr">132 </span>  row:num <span class="Special">&lt;-</span> copy<span class="Constant"> 0</span>
 <span id="L133" class="LineNr">133 </span>  <span class="Delimiter">{</span>
-<span id="L134" class="LineNr">134 </span>  <span class="Conceal">¦</span> done?:bool <span class="Special">&lt;-</span> equal row,<span class="Constant"> 8</span>
-<span id="L135" class="LineNr">135 </span>  <span class="Conceal">¦</span> <span class="muControl">break-if</span> done?
-<span id="L136" class="LineNr">136 </span>  <span class="Conceal">¦</span> square:char <span class="Special">&lt;-</span> index *position, index
-<span id="L137" class="LineNr">137 </span>  <span class="Conceal">¦</span> *result <span class="Special">&lt;-</span> put-index *result, row, square
-<span id="L138" class="LineNr">138 </span>  <span class="Conceal">¦</span> row <span class="Special">&lt;-</span> add row,<span class="Constant"> 1</span>
-<span id="L139" class="LineNr">139 </span>  <span class="Conceal">¦</span> index <span class="Special">&lt;-</span> add index,<span class="Constant"> 1</span>
-<span id="L140" class="LineNr">140 </span>  <span class="Conceal">¦</span><span class="muControl"> loop</span>
+<span id="L134" class="LineNr">134 </span>    done?:bool <span class="Special">&lt;-</span> equal row,<span class="Constant"> 8</span>
+<span id="L135" class="LineNr">135 </span>    <span class="muControl">break-if</span> done?
+<span id="L136" class="LineNr">136 </span>    square:char <span class="Special">&lt;-</span> index *position, index
+<span id="L137" class="LineNr">137 </span>    *result <span class="Special">&lt;-</span> put-index *result, row, square
+<span id="L138" class="LineNr">138 </span>    row <span class="Special">&lt;-</span> add row,<span class="Constant"> 1</span>
+<span id="L139" class="LineNr">139 </span>    index <span class="Special">&lt;-</span> add index,<span class="Constant"> 1</span>
+<span id="L140" class="LineNr">140 </span>   <span class="muControl"> loop</span>
 <span id="L141" class="LineNr">141 </span>  <span class="Delimiter">}</span>
 <span id="L142" class="LineNr">142 </span>]
 <span id="L143" class="LineNr">143 </span>
-<span id="L144" class="LineNr">144 </span><span class="muRecipe">def</span> print <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a>, <a href='chessboard.mu.html#L67'>board</a>:<a href='chessboard.mu.html#L67'>board</a><span class="muRecipe"> -&gt; </span><a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a> [
+<span id="L144" class="LineNr">144 </span><span class="muRecipe">def</span> print screen:&amp;:screen, board:board<span class="muRecipe"> -&gt; </span>screen:&amp;:screen [
 <span id="L145" class="LineNr">145 </span>  <span class="Constant">local-scope</span>
 <span id="L146" class="LineNr">146 </span>  <span class="Constant">load-inputs</span>
 <span id="L147" class="LineNr">147 </span>  row:num <span class="Special">&lt;-</span> copy<span class="Constant"> 7</span>  <span class="Comment"># start printing from the top of the board</span>
 <span id="L148" class="LineNr">148 </span>  space:char <span class="Special">&lt;-</span> copy <span class="Constant">32/space</span>
 <span id="L149" class="LineNr">149 </span>  <span class="Comment"># print each row</span>
 <span id="L150" class="LineNr">150 </span>  <span class="Delimiter">{</span>
-<span id="L151" class="LineNr">151 </span>  <span class="Conceal">¦</span> done?:bool <span class="Special">&lt;-</span> lesser-than row,<span class="Constant"> 0</span>
-<span id="L152" class="LineNr">152 </span>  <span class="Conceal">¦</span> <span class="muControl">break-if</span> done?
-<span id="L153" class="LineNr">153 </span>  <span class="Conceal">¦</span> <span class="Comment"># print rank number as a legend</span>
-<span id="L154" class="LineNr">154 </span>  <span class="Conceal">¦</span> rank:num <span class="Special">&lt;-</span> add row,<span class="Constant"> 1</span>
-<span id="L155" class="LineNr">155 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, rank
-<span id="L156" class="LineNr">156 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[ | ]</span>
-<span id="L157" class="LineNr">157 </span>  <span class="Conceal">¦</span> <span class="Comment"># print each square in the row</span>
-<span id="L158" class="LineNr">158 </span>  <span class="Conceal">¦</span> col:num <span class="Special">&lt;-</span> copy<span class="Constant"> 0</span>
-<span id="L159" class="LineNr">159 </span>  <span class="Conceal">¦</span> <span class="Delimiter">{</span>
-<span id="L160" class="LineNr">160 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> done?:bool <span class="Special">&lt;-</span> equal col:num,<span class="Constant"> 8</span>
-<span id="L161" class="LineNr">161 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> <span class="muControl">break-if</span> done?
-<span id="L162" class="LineNr">162 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> f:&amp;:@:char <span class="Special">&lt;-</span> index *board, col
-<span id="L163" class="LineNr">163 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> c:char <span class="Special">&lt;-</span> index *f, row
-<span id="L164" class="LineNr">164 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> bg:num <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L181'>square-color</a> row, col
-<span id="L165" class="LineNr">165 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, c, <span class="Constant">7/white</span>, bg
-<span id="L166" class="LineNr">166 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, space
-<span id="L167" class="LineNr">167 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span> col <span class="Special">&lt;-</span> add col,<span class="Constant"> 1</span>
-<span id="L168" class="LineNr">168 </span>  <span class="Conceal">¦</span> <span class="Conceal">¦</span><span class="muControl"> loop</span>
-<span id="L169" class="LineNr">169 </span>  <span class="Conceal">¦</span> <span class="Delimiter">}</span>
-<span id="L170" class="LineNr">170 </span>  <span class="Conceal">¦</span> row <span class="Special">&lt;-</span> subtract row,<span class="Constant"> 1</span>
-<span id="L171" class="LineNr">171 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L752'>cursor-to-next-line</a> <a href='081print.mu.html#L16'>screen</a>
-<span id="L172" class="LineNr">172 </span>  <span class="Conceal">¦</span><span class="muControl"> loop</span>
+<span id="L151" class="LineNr">151 </span>    done?:bool <span class="Special">&lt;-</span> lesser-than row,<span class="Constant"> 0</span>
+<span id="L152" class="LineNr">152 </span>    <span class="muControl">break-if</span> done?
+<span id="L153" class="LineNr">153 </span>    <span class="Comment"># print rank number as a legend</span>
+<span id="L154" class="LineNr">154 </span>    rank:num <span class="Special">&lt;-</span> add row,<span class="Constant"> 1</span>
+<span id="L155" class="LineNr">155 </span>    print screen, rank
+<span id="L156" class="LineNr">156 </span>    print screen, <span class="Constant">[ | ]</span>
+<span id="L157" class="LineNr">157 </span>    <span class="Comment"># print each square in the row</span>
+<span id="L158" class="LineNr">158 </span>    col:num <span class="Special">&lt;-</span> copy<span class="Constant"> 0</span>
+<span id="L159" class="LineNr">159 </span>    <span class="Delimiter">{</span>
+<span id="L160" class="LineNr">160 </span>      done?:bool <span class="Special">&lt;-</span> equal col:num,<span class="Constant"> 8</span>
+<span id="L161" class="LineNr">161 </span>      <span class="muControl">break-if</span> done?
+<span id="L162" class="LineNr">162 </span>      f:&amp;:@:char <span class="Special">&lt;-</span> index *board, col
+<span id="L163" class="LineNr">163 </span>      c:char <span class="Special">&lt;-</span> index *f, row
+<span id="L164" class="LineNr">164 </span>      bg:num <span class="Special">&lt;-</span> square-color row, col
+<span id="L165" class="LineNr">165 </span>      print screen, c, <span class="Constant">7/white</span>, bg
+<span id="L166" class="LineNr">166 </span>      print screen, space
+<span id="L167" class="LineNr">167 </span>      col <span class="Special">&lt;-</span> add col,<span class="Constant"> 1</span>
+<span id="L168" class="LineNr">168 </span>     <span class="muControl"> loop</span>
+<span id="L169" class="LineNr">169 </span>    <span class="Delimiter">}</span>
+<span id="L170" class="LineNr">170 </span>    row <span class="Special">&lt;-</span> subtract row,<span class="Constant"> 1</span>
+<span id="L171" class="LineNr">171 </span>    cursor-to-next-line screen
+<span id="L172" class="LineNr">172 </span>   <span class="muControl"> loop</span>
 <span id="L173" class="LineNr">173 </span>  <span class="Delimiter">}</span>
 <span id="L174" class="LineNr">174 </span>  <span class="Comment"># print file letters as legend</span>
-<span id="L175" class="LineNr">175 </span>  print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[  +----------------]</span>
-<span id="L176" class="LineNr">176 </span>  <a href='081print.mu.html#L752'>cursor-to-next-line</a> <a href='081print.mu.html#L16'>screen</a>
-<span id="L177" class="LineNr">177 </span>  print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[    a b c d e f g h]</span>
-<span id="L178" class="LineNr">178 </span>  <a href='081print.mu.html#L752'>cursor-to-next-line</a> <a href='081print.mu.html#L16'>screen</a>
+<span id="L175" class="LineNr">175 </span>  print screen, <span class="Constant">[  +----------------]</span>
+<span id="L176" class="LineNr">176 </span>  cursor-to-next-line screen
+<span id="L177" class="LineNr">177 </span>  print screen, <span class="Constant">[    a b c d e f g h]</span>
+<span id="L178" class="LineNr">178 </span>  cursor-to-next-line screen
 <span id="L179" class="LineNr">179 </span>]
 <span id="L180" class="LineNr">180 </span>
-<span id="L181" class="LineNr">181 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L181'>square-color</a> row:num, col:num<span class="muRecipe"> -&gt; </span>result:num [
+<span id="L181" class="LineNr">181 </span><span class="muRecipe">def</span> square-color row:num, col:num<span class="muRecipe"> -&gt; </span>result:num [
 <span id="L182" class="LineNr">182 </span>  <span class="Constant">local-scope</span>
 <span id="L183" class="LineNr">183 </span>  <span class="Constant">load-inputs</span>
 <span id="L184" class="LineNr">184 </span>  result <span class="Special">&lt;-</span> copy <span class="Constant">0/black</span>
@@ -251,7 +250,7 @@ if ('onhashchange' in window) {
 <span id="L187" class="LineNr">187 </span>  <span class="muControl">return-if</span> rem,<span class="Constant"> 238</span>
 <span id="L188" class="LineNr">188 </span>]
 <span id="L189" class="LineNr">189 </span>
-<span id="L190" class="LineNr">190 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L190'>initial-position</a><span class="muRecipe"> -&gt; </span><a href='chessboard.mu.html#L67'>board</a>:<a href='chessboard.mu.html#L67'>board</a> [
+<span id="L190" class="LineNr">190 </span><span class="muRecipe">def</span> initial-position<span class="muRecipe"> -&gt; </span>board:board [
 <span id="L191" class="LineNr">191 </span>  <span class="Constant">local-scope</span>
 <span id="L192" class="LineNr">192 </span>  <span class="Comment"># layout in memory (in raster order):</span>
 <span id="L193" class="LineNr">193 </span>  <span class="Comment">#   R P _ _ _ _ p r</span>
@@ -262,7 +261,7 @@ if ('onhashchange' in window) {
 <span id="L198" class="LineNr">198 </span>  <span class="Comment">#   B P _ _ _ _ p B</span>
 <span id="L199" class="LineNr">199 </span>  <span class="Comment">#   N P _ _ _ _ p n</span>
 <span id="L200" class="LineNr">200 </span>  <span class="Comment">#   R P _ _ _ _ p r</span>
-<span id="L201" class="LineNr">201 </span>  <a href='chessboard.mu.html#L190'>initial-position</a>:&amp;:@:char <span class="Special">&lt;-</span> <a href='063array.mu.html#L16'>new-array</a> <span class="Constant">82/R</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">114/r</span>, <span class="Constant">78/N</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">110/n</span>, <span class="Constant">66/B</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">98/b</span>, <span class="Constant">81/Q</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">113/q</span>, <span class="Constant">75/K</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">107/k</span>, <span class="Constant">66/B</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">98/b</span>, <span class="Constant">78/N</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">110/n</span>, <span class="Constant">82/R</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">114/r</span>
+<span id="L201" class="LineNr">201 </span>  initial-position:&amp;:@:char <span class="Special">&lt;-</span> new-array <span class="Constant">82/R</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">114/r</span>, <span class="Constant">78/N</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">110/n</span>, <span class="Constant">66/B</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">98/b</span>, <span class="Constant">81/Q</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">113/q</span>, <span class="Constant">75/K</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">107/k</span>, <span class="Constant">66/B</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">98/b</span>, <span class="Constant">78/N</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">110/n</span>, <span class="Constant">82/R</span>, <span class="Constant">80/P</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">32/blank</span>, <span class="Constant">112/p</span>, <span class="Constant">114/r</span>
 <span id="L202" class="LineNr">202 </span><span class="CommentedCode">#?       82/R, 80/P, 32/blank, 32/blank, 32/blank, 32/blank, 112/p, 114/r,</span>
 <span id="L203" class="LineNr">203 </span><span class="CommentedCode">#?       78/N, 80/P, 32/blank, 32/blank, 32/blank, 32/blank, 112/p, 110/n,</span>
 <span id="L204" class="LineNr">204 </span><span class="CommentedCode">#?       66/B, 80/P, 32/blank, 32/blank, 32/blank, 32/blank, 112/p, 98/b, </span>
@@ -271,36 +270,36 @@ if ('onhashchange' in window) {
 <span id="L207" class="LineNr">207 </span><span class="CommentedCode">#?       66/B, 80/P, 32/blank, 32/blank, 32/blank, 32/blank, 112/p, 98/b,</span>
 <span id="L208" class="LineNr">208 </span><span class="CommentedCode">#?       78/N, 80/P, 32/blank, 32/blank, 32/blank, 32/blank, 112/p, 110/n,</span>
 <span id="L209" class="LineNr">209 </span><span class="CommentedCode">#?       82/R, 80/P, 32/blank, 32/blank, 32/blank, 32/blank, 112/p, 114/r</span>
-<span id="L210" class="LineNr">210 </span>  <a href='chessboard.mu.html#L67'>board</a> <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L107'>new-board</a> <a href='chessboard.mu.html#L190'>initial-position</a>
+<span id="L210" class="LineNr">210 </span>  board <span class="Special">&lt;-</span> new-board initial-position
 <span id="L211" class="LineNr">211 </span>]
 <span id="L212" class="LineNr">212 </span>
 <span id="L213" class="LineNr">213 </span><span class="muScenario">scenario</span> printing-the-board [
 <span id="L214" class="LineNr">214 </span>  <span class="Constant">local-scope</span>
-<span id="L215" class="LineNr">215 </span>  <a href='chessboard.mu.html#L67'>board</a>:<a href='chessboard.mu.html#L67'>board</a> <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L190'>initial-position</a>
+<span id="L215" class="LineNr">215 </span>  board:board <span class="Special">&lt;-</span> initial-position
 <span id="L216" class="LineNr">216 </span>  assume-screen <span class="Constant">30/width</span>, <span class="Constant">12/height</span>
 <span id="L217" class="LineNr">217 </span>  run [
-<span id="L218" class="LineNr">218 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L16'>screen</a> <span class="Special">&lt;-</span> print <a href='081print.mu.html#L16'>screen</a>, <a href='chessboard.mu.html#L67'>board</a>
+<span id="L218" class="LineNr">218 </span>    screen <span class="Special">&lt;-</span> print screen, board
 <span id="L219" class="LineNr">219 </span>  ]
 <span id="L220" class="LineNr">220 </span>  screen-should-contain [
 <span id="L221" class="LineNr">221 </span>  <span class="Comment">#  012345678901234567890123456789</span>
-<span id="L222" class="LineNr">222 </span>  <span class="Conceal">¦</span><span class="Constant"> .8 | r n b q k b n r           .</span>
-<span id="L223" class="LineNr">223 </span>  <span class="Conceal">¦</span><span class="Constant"> .7 | p p p p p p p p           .</span>
-<span id="L224" class="LineNr">224 </span>  <span class="Conceal">¦</span><span class="Constant"> .6 |                           .</span>
-<span id="L225" class="LineNr">225 </span>  <span class="Conceal">¦</span><span class="Constant"> .5 |                           .</span>
-<span id="L226" class="LineNr">226 </span>  <span class="Conceal">¦</span><span class="Constant"> .4 |                           .</span>
-<span id="L227" class="LineNr">227 </span>  <span class="Conceal">¦</span><span class="Constant"> .3 |                           .</span>
-<span id="L228" class="LineNr">228 </span>  <span class="Conceal">¦</span><span class="Constant"> .2 | P P P P P P P P           .</span>
-<span id="L229" class="LineNr">229 </span>  <span class="Conceal">¦</span><span class="Constant"> .1 | R N B Q K B N R           .</span>
-<span id="L230" class="LineNr">230 </span>  <span class="Conceal">¦</span><span class="Constant"> .  +----------------           .</span>
-<span id="L231" class="LineNr">231 </span>  <span class="Conceal">¦</span><span class="Constant"> .    a b c d e f g h           .</span>
-<span id="L232" class="LineNr">232 </span>  <span class="Conceal">¦</span><span class="Constant"> .                              .</span>
-<span id="L233" class="LineNr">233 </span>  <span class="Conceal">¦</span><span class="Constant"> .                              .</span>
+<span id="L222" class="LineNr">222 </span>   <span class="Constant"> .8 | r n b q k b n r           .</span>
+<span id="L223" class="LineNr">223 </span>   <span class="Constant"> .7 | p p p p p p p p           .</span>
+<span id="L224" class="LineNr">224 </span>   <span class="Constant"> .6 |                           .</span>
+<span id="L225" class="LineNr">225 </span>   <span class="Constant"> .5 |                           .</span>
+<span id="L226" class="LineNr">226 </span>   <span class="Constant"> .4 |                           .</span>
+<span id="L227" class="LineNr">227 </span>   <span class="Constant"> .3 |                           .</span>
+<span id="L228" class="LineNr">228 </span>   <span class="Constant"> .2 | P P P P P P P P           .</span>
+<span id="L229" class="LineNr">229 </span>   <span class="Constant"> .1 | R N B Q K B N R           .</span>
+<span id="L230" class="LineNr">230 </span>   <span class="Constant"> .  +----------------           .</span>
+<span id="L231" class="LineNr">231 </span>   <span class="Constant"> .    a b c d e f g h           .</span>
+<span id="L232" class="LineNr">232 </span>   <span class="Constant"> .                              .</span>
+<span id="L233" class="LineNr">233 </span>   <span class="Constant"> .                              .</span>
 <span id="L234" class="LineNr">234 </span>  ]
 <span id="L235" class="LineNr">235 </span>]
 <span id="L236" class="LineNr">236 </span>
 <span id="L237" class="LineNr">237 </span><span class="SalientComment">## data structure: move</span>
 <span id="L238" class="LineNr">238 </span>
-<span id="L239" class="LineNr">239 </span><span class="muData">container</span> <a href='chessboard.mu.html#L239'>move</a> [
+<span id="L239" class="LineNr">239 </span><span class="muData">container</span> move [
 <span id="L240" class="LineNr">240 </span>  <span class="Comment"># valid range: 0-7</span>
 <span id="L241" class="LineNr">241 </span>  from-file:num
 <span id="L242" class="LineNr">242 </span>  from-rank:num
@@ -309,35 +308,35 @@ if ('onhashchange' in window) {
 <span id="L245" class="LineNr">245 </span>]
 <span id="L246" class="LineNr">246 </span>
 <span id="L247" class="LineNr">247 </span><span class="Comment"># prints only error messages to screen</span>
-<span id="L248" class="LineNr">248 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L248'>read-move</a> stdin:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a><span class="muRecipe"> -&gt; </span>result:&amp;:<a href='chessboard.mu.html#L239'>move</a>, quit?:bool, error?:bool, stdin:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a> [
+<span id="L248" class="LineNr">248 </span><span class="muRecipe">def</span> read-move stdin:&amp;:source:char, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>result:&amp;:move, quit?:bool, error?:bool, stdin:&amp;:source:char, screen:&amp;:screen [
 <span id="L249" class="LineNr">249 </span>  <span class="Constant">local-scope</span>
 <span id="L250" class="LineNr">250 </span>  <span class="Constant">load-inputs</span>
-<span id="L251" class="LineNr">251 </span>  from-file:num, quit?:bool, error?:bool <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L276'>read-file</a> stdin, <a href='081print.mu.html#L16'>screen</a>
+<span id="L251" class="LineNr">251 </span>  from-file:num, quit?:bool, error?:bool <span class="Special">&lt;-</span> read-file stdin, screen
 <span id="L252" class="LineNr">252 </span>  <span class="muControl">return-if</span> quit?, <span class="Constant">0/dummy</span>
 <span id="L253" class="LineNr">253 </span>  <span class="muControl">return-if</span> error?, <span class="Constant">0/dummy</span>
 <span id="L254" class="LineNr">254 </span>  <span class="Comment"># construct the move object</span>
-<span id="L255" class="LineNr">255 </span>  result:&amp;:<a href='chessboard.mu.html#L239'>move</a> <span class="Special">&lt;-</span> new <span class="Constant"><a href='chessboard.mu.html#L239'>move</a>:type</span>
+<span id="L255" class="LineNr">255 </span>  result:&amp;:move <span class="Special">&lt;-</span> new <span class="Constant">move:type</span>
 <span id="L256" class="LineNr">256 </span>  *result <span class="Special">&lt;-</span> put *result, <span class="Constant">from-file:offset</span>, from-file
-<span id="L257" class="LineNr">257 </span>  from-rank:num, quit?, error? <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L314'>read-rank</a> stdin, <a href='081print.mu.html#L16'>screen</a>
+<span id="L257" class="LineNr">257 </span>  from-rank:num, quit?, error? <span class="Special">&lt;-</span> read-rank stdin, screen
 <span id="L258" class="LineNr">258 </span>  <span class="muControl">return-if</span> quit?, <span class="Constant">0/dummy</span>
 <span id="L259" class="LineNr">259 </span>  <span class="muControl">return-if</span> error?, <span class="Constant">0/dummy</span>
 <span id="L260" class="LineNr">260 </span>  *result <span class="Special">&lt;-</span> put *result, <span class="Constant">from-rank:offset</span>, from-rank
-<span id="L261" class="LineNr">261 </span>  error? <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L352'>expect-from-channel</a> stdin, <span class="Constant">45/dash</span>, <a href='081print.mu.html#L16'>screen</a>
+<span id="L261" class="LineNr">261 </span>  error? <span class="Special">&lt;-</span> expect-from-channel stdin, <span class="Constant">45/dash</span>, screen
 <span id="L262" class="LineNr">262 </span>  <span class="muControl">return-if</span> error?, <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>
-<span id="L263" class="LineNr">263 </span>  to-file:num, quit?, error? <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L276'>read-file</a> stdin, <a href='081print.mu.html#L16'>screen</a>
+<span id="L263" class="LineNr">263 </span>  to-file:num, quit?, error? <span class="Special">&lt;-</span> read-file stdin, screen
 <span id="L264" class="LineNr">264 </span>  <span class="muControl">return-if</span> quit?, <span class="Constant">0/dummy</span>
 <span id="L265" class="LineNr">265 </span>  <span class="muControl">return-if</span> error?, <span class="Constant">0/dummy</span>
 <span id="L266" class="LineNr">266 </span>  *result <span class="Special">&lt;-</span> put *result, <span class="Constant">to-file:offset</span>, to-file
-<span id="L267" class="LineNr">267 </span>  to-rank:num, quit?, error? <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L314'>read-rank</a> stdin, <a href='081print.mu.html#L16'>screen</a>
+<span id="L267" class="LineNr">267 </span>  to-rank:num, quit?, error? <span class="Special">&lt;-</span> read-rank stdin, screen
 <span id="L268" class="LineNr">268 </span>  <span class="muControl">return-if</span> quit?, <span class="Constant">0/dummy</span>
 <span id="L269" class="LineNr">269 </span>  <span class="muControl">return-if</span> error?, <span class="Constant">0/dummy</span>
 <span id="L270" class="LineNr">270 </span>  *result <span class="Special">&lt;-</span> put *result, <span class="Constant">to-rank:offset</span>, to-rank
-<span id="L271" class="LineNr">271 </span>  error? <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L352'>expect-from-channel</a> stdin, <span class="Constant">10/newline</span>, <a href='081print.mu.html#L16'>screen</a>
+<span id="L271" class="LineNr">271 </span>  error? <span class="Special">&lt;-</span> expect-from-channel stdin, <span class="Constant">10/newline</span>, screen
 <span id="L272" class="LineNr">272 </span>  <span class="muControl">return-if</span> error?, <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>
 <span id="L273" class="LineNr">273 </span>]
 <span id="L274" class="LineNr">274 </span>
 <span id="L275" class="LineNr">275 </span><span class="Comment"># valid values for file: 0-7</span>
-<span id="L276" class="LineNr">276 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L276'>read-file</a> stdin:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a><span class="muRecipe"> -&gt; </span>file:num, quit:bool, error:bool, stdin:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a> [
+<span id="L276" class="LineNr">276 </span><span class="muRecipe">def</span> read-file stdin:&amp;:source:char, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>file:num, quit:bool, error:bool, stdin:&amp;:source:char, screen:&amp;:screen [
 <span id="L277" class="LineNr">277 </span>  <span class="Constant">local-scope</span>
 <span id="L278" class="LineNr">278 </span>  <span class="Constant">load-inputs</span>
 <span id="L279" class="LineNr">279 </span>  c:char, eof?:bool, stdin <span class="Special">&lt;-</span> read stdin
@@ -349,33 +348,33 @@ if ('onhashchange' in window) {
 <span id="L285" class="LineNr">285 </span>  empty-fake-keyboard?:bool <span class="Special">&lt;-</span> equal c, <span class="Constant">0/eof</span>
 <span id="L286" class="LineNr">286 </span>  <span class="muControl">return-if</span> empty-fake-keyboard?, <span class="Constant">0/dummy</span>, <span class="Constant">1/quit</span>, <span class="Constant">0/error</span>
 <span id="L287" class="LineNr">287 </span>  <span class="Delimiter">{</span>
-<span id="L288" class="LineNr">288 </span>  <span class="Conceal">¦</span> newline?:bool <span class="Special">&lt;-</span> equal c, <span class="Constant">10/newline</span>
-<span id="L289" class="LineNr">289 </span>  <span class="Conceal">¦</span> <span class="muControl">break-unless</span> newline?
-<span id="L290" class="LineNr">290 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[that's not enough]</span>
-<span id="L291" class="LineNr">291 </span>  <span class="Conceal">¦</span><span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
+<span id="L288" class="LineNr">288 </span>    newline?:bool <span class="Special">&lt;-</span> equal c, <span class="Constant">10/newline</span>
+<span id="L289" class="LineNr">289 </span>    <span class="muControl">break-unless</span> newline?
+<span id="L290" class="LineNr">290 </span>    print screen, <span class="Constant">[that's not enough]</span>
+<span id="L291" class="LineNr">291 </span>   <span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
 <span id="L292" class="LineNr">292 </span>  <span class="Delimiter">}</span>
 <span id="L293" class="LineNr">293 </span>  file:num <span class="Special">&lt;-</span> subtract c, <span class="Constant">97/a</span>
 <span id="L294" class="LineNr">294 </span>  <span class="Comment"># 'a' &lt;= file &lt;= 'h'</span>
 <span id="L295" class="LineNr">295 </span>  <span class="Delimiter">{</span>
-<span id="L296" class="LineNr">296 </span>  <span class="Conceal">¦</span> above-min:bool <span class="Special">&lt;-</span> greater-or-equal file,<span class="Constant"> 0</span>
-<span id="L297" class="LineNr">297 </span>  <span class="Conceal">¦</span> <span class="muControl">break-if</span> above-min
-<span id="L298" class="LineNr">298 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[file too low: ]</span>
-<span id="L299" class="LineNr">299 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, c
-<span id="L300" class="LineNr">300 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L752'>cursor-to-next-line</a> <a href='081print.mu.html#L16'>screen</a>
-<span id="L301" class="LineNr">301 </span>  <span class="Conceal">¦</span><span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
+<span id="L296" class="LineNr">296 </span>    above-min:bool <span class="Special">&lt;-</span> greater-or-equal file,<span class="Constant"> 0</span>
+<span id="L297" class="LineNr">297 </span>    <span class="muControl">break-if</span> above-min
+<span id="L298" class="LineNr">298 </span>    print screen, <span class="Constant">[file too low: ]</span>
+<span id="L299" class="LineNr">299 </span>    print screen, c
+<span id="L300" class="LineNr">300 </span>    cursor-to-next-line screen
+<span id="L301" class="LineNr">301 </span>   <span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
 <span id="L302" class="LineNr">302 </span>  <span class="Delimiter">}</span>
 <span id="L303" class="LineNr">303 </span>  <span class="Delimiter">{</span>
-<span id="L304" class="LineNr">304 </span>  <span class="Conceal">¦</span> below-max:bool <span class="Special">&lt;-</span> lesser-than file,<span class="Constant"> 8</span>
-<span id="L305" class="LineNr">305 </span>  <span class="Conceal">¦</span> <span class="muControl">break-if</span> below-max
-<span id="L306" class="LineNr">306 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[file too high: ]</span>
-<span id="L307" class="LineNr">307 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, c
-<span id="L308" class="LineNr">308 </span>  <span class="Conceal">¦</span><span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
+<span id="L304" class="LineNr">304 </span>    below-max:bool <span class="Special">&lt;-</span> lesser-than file,<span class="Constant"> 8</span>
+<span id="L305" class="LineNr">305 </span>    <span class="muControl">break-if</span> below-max
+<span id="L306" class="LineNr">306 </span>    print screen, <span class="Constant">[file too high: ]</span>
+<span id="L307" class="LineNr">307 </span>    print screen, c
+<span id="L308" class="LineNr">308 </span>   <span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
 <span id="L309" class="LineNr">309 </span>  <span class="Delimiter">}</span>
 <span id="L310" class="LineNr">310 </span> <span class="muControl"> return</span> file, <span class="Constant">0/quit</span>, <span class="Constant">0/error</span>
 <span id="L311" class="LineNr">311 </span>]
 <span id="L312" class="LineNr">312 </span>
 <span id="L313" class="LineNr">313 </span><span class="Comment"># valid values for rank: 0-7</span>
-<span id="L314" class="LineNr">314 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L314'>read-rank</a> stdin:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a><span class="muRecipe"> -&gt; </span>rank:num, quit?:bool, error?:bool, stdin:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a> [
+<span id="L314" class="LineNr">314 </span><span class="muRecipe">def</span> read-rank stdin:&amp;:source:char, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>rank:num, quit?:bool, error?:bool, stdin:&amp;:source:char, screen:&amp;:screen [
 <span id="L315" class="LineNr">315 </span>  <span class="Constant">local-scope</span>
 <span id="L316" class="LineNr">316 </span>  <span class="Constant">load-inputs</span>
 <span id="L317" class="LineNr">317 </span>  c:char, eof?:bool, stdin <span class="Special">&lt;-</span> read stdin
@@ -387,41 +386,41 @@ if ('onhashchange' in window) {
 <span id="L323" class="LineNr">323 </span>  empty-fake-keyboard?:bool <span class="Special">&lt;-</span> equal c, <span class="Constant">0/eof</span>
 <span id="L324" class="LineNr">324 </span>  <span class="muControl">return-if</span> empty-fake-keyboard?, <span class="Constant">0/dummy</span>, <span class="Constant">1/quit</span>, <span class="Constant">0/error</span>
 <span id="L325" class="LineNr">325 </span>  <span class="Delimiter">{</span>
-<span id="L326" class="LineNr">326 </span>  <span class="Conceal">¦</span> newline?:bool <span class="Special">&lt;-</span> equal c,<span class="Constant"> 10</span>  <span class="Comment"># newline</span>
-<span id="L327" class="LineNr">327 </span>  <span class="Conceal">¦</span> <span class="muControl">break-unless</span> newline?
-<span id="L328" class="LineNr">328 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[that's not enough]</span>
-<span id="L329" class="LineNr">329 </span>  <span class="Conceal">¦</span><span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
+<span id="L326" class="LineNr">326 </span>    newline?:bool <span class="Special">&lt;-</span> equal c,<span class="Constant"> 10</span>  <span class="Comment"># newline</span>
+<span id="L327" class="LineNr">327 </span>    <span class="muControl">break-unless</span> newline?
+<span id="L328" class="LineNr">328 </span>    print screen, <span class="Constant">[that's not enough]</span>
+<span id="L329" class="LineNr">329 </span>   <span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
 <span id="L330" class="LineNr">330 </span>  <span class="Delimiter">}</span>
 <span id="L331" class="LineNr">331 </span>  rank:num <span class="Special">&lt;-</span> subtract c, <span class="Constant">49/'1'</span>
 <span id="L332" class="LineNr">332 </span>  <span class="Comment"># assert'1' &lt;= rank &lt;= '8'</span>
 <span id="L333" class="LineNr">333 </span>  <span class="Delimiter">{</span>
-<span id="L334" class="LineNr">334 </span>  <span class="Conceal">¦</span> above-min:bool <span class="Special">&lt;-</span> greater-or-equal rank,<span class="Constant"> 0</span>
-<span id="L335" class="LineNr">335 </span>  <span class="Conceal">¦</span> <span class="muControl">break-if</span> above-min
-<span id="L336" class="LineNr">336 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[rank too low: ]</span>
-<span id="L337" class="LineNr">337 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, c
-<span id="L338" class="LineNr">338 </span>  <span class="Conceal">¦</span><span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
+<span id="L334" class="LineNr">334 </span>    above-min:bool <span class="Special">&lt;-</span> greater-or-equal rank,<span class="Constant"> 0</span>
+<span id="L335" class="LineNr">335 </span>    <span class="muControl">break-if</span> above-min
+<span id="L336" class="LineNr">336 </span>    print screen, <span class="Constant">[rank too low: ]</span>
+<span id="L337" class="LineNr">337 </span>    print screen, c
+<span id="L338" class="LineNr">338 </span>   <span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
 <span id="L339" class="LineNr">339 </span>  <span class="Delimiter">}</span>
 <span id="L340" class="LineNr">340 </span>  <span class="Delimiter">{</span>
-<span id="L341" class="LineNr">341 </span>  <span class="Conceal">¦</span> below-max:bool <span class="Special">&lt;-</span> lesser-or-equal rank,<span class="Constant"> 7</span>
-<span id="L342" class="LineNr">342 </span>  <span class="Conceal">¦</span> <span class="muControl">break-if</span> below-max
-<span id="L343" class="LineNr">343 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[rank too high: ]</span>
-<span id="L344" class="LineNr">344 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, c
-<span id="L345" class="LineNr">345 </span>  <span class="Conceal">¦</span><span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
+<span id="L341" class="LineNr">341 </span>    below-max:bool <span class="Special">&lt;-</span> lesser-or-equal rank,<span class="Constant"> 7</span>
+<span id="L342" class="LineNr">342 </span>    <span class="muControl">break-if</span> below-max
+<span id="L343" class="LineNr">343 </span>    print screen, <span class="Constant">[rank too high: ]</span>
+<span id="L344" class="LineNr">344 </span>    print screen, c
+<span id="L345" class="LineNr">345 </span>   <span class="muControl"> return</span> <span class="Constant">0/dummy</span>, <span class="Constant">0/quit</span>, <span class="Constant">1/error</span>
 <span id="L346" class="LineNr">346 </span>  <span class="Delimiter">}</span>
 <span id="L347" class="LineNr">347 </span> <span class="muControl"> return</span> rank, <span class="Constant">0/quit</span>, <span class="Constant">0/error</span>
 <span id="L348" class="LineNr">348 </span>]
 <span id="L349" class="LineNr">349 </span>
 <span id="L350" class="LineNr">350 </span><span class="Comment"># read a character from the given channel and check that it's what we expect</span>
 <span id="L351" class="LineNr">351 </span><span class="Comment"># return true on error</span>
-<span id="L352" class="LineNr">352 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L352'>expect-from-channel</a> stdin:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, expected:char, <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a><span class="muRecipe"> -&gt; </span>result:bool, stdin:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='081print.mu.html#L16'>screen</a>:&amp;:<a href='081print.mu.html#L16'>screen</a> [
+<span id="L352" class="LineNr">352 </span><span class="muRecipe">def</span> expect-from-channel stdin:&amp;:source:char, expected:char, screen:&amp;:screen<span class="muRecipe"> -&gt; </span>result:bool, stdin:&amp;:source:char, screen:&amp;:screen [
 <span id="L353" class="LineNr">353 </span>  <span class="Constant">local-scope</span>
 <span id="L354" class="LineNr">354 </span>  <span class="Constant">load-inputs</span>
 <span id="L355" class="LineNr">355 </span>  c:char, eof?:bool, stdin <span class="Special">&lt;-</span> read stdin
 <span id="L356" class="LineNr">356 </span>  <span class="muControl">return-if</span> eof? <span class="Constant">1/true</span>
 <span id="L357" class="LineNr">357 </span>  <span class="Delimiter">{</span>
-<span id="L358" class="LineNr">358 </span>  <span class="Conceal">¦</span> match?:bool <span class="Special">&lt;-</span> equal c, expected
-<span id="L359" class="LineNr">359 </span>  <span class="Conceal">¦</span> <span class="muControl">break-if</span> match?
-<span id="L360" class="LineNr">360 </span>  <span class="Conceal">¦</span> print <a href='081print.mu.html#L16'>screen</a>, <span class="Constant">[expected character not found]</span>
+<span id="L358" class="LineNr">358 </span>    match?:bool <span class="Special">&lt;-</span> equal c, expected
+<span id="L359" class="LineNr">359 </span>    <span class="muControl">break-if</span> match?
+<span id="L360" class="LineNr">360 </span>    print screen, <span class="Constant">[expected character not found]</span>
 <span id="L361" class="LineNr">361 </span>  <span class="Delimiter">}</span>
 <span id="L362" class="LineNr">362 </span>  result <span class="Special">&lt;-</span> not match?
 <span id="L363" class="LineNr">363 </span>]
@@ -429,173 +428,173 @@ if ('onhashchange' in window) {
 <span id="L365" class="LineNr">365 </span><span class="muScenario">scenario</span> read-move-blocking [
 <span id="L366" class="LineNr">366 </span>  <span class="Constant">local-scope</span>
 <span id="L367" class="LineNr">367 </span>  assume-screen <span class="Constant">20/width</span>, <span class="Constant">2/height</span>
-<span id="L368" class="LineNr">368 </span>  <a href='075channel.mu.html#L43'>source</a>:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='075channel.mu.html#L47'>sink</a>:&amp;:<a href='075channel.mu.html#L47'>sink</a>:char <span class="Special">&lt;-</span> <a href='075channel.mu.html#L51'>new-channel</a> <span class="Constant">2/capacity</span>
-<span id="L369" class="LineNr">369 </span>  read-move-routine:num/routine <span class="Special">&lt;-</span> <span class="muControl">start-running</span> <a href='chessboard.mu.html#L248'>read-move</a>, <a href='075channel.mu.html#L43'>source</a>, <a href='081print.mu.html#L16'>screen</a>
+<span id="L368" class="LineNr">368 </span>  source:&amp;:source:char, sink:&amp;:sink:char <span class="Special">&lt;-</span> new-channel <span class="Constant">2/capacity</span>
+<span id="L369" class="LineNr">369 </span>  read-move-routine:num/routine <span class="Special">&lt;-</span> <span class="muControl">start-running</span> read-move, source, screen
 <span id="L370" class="LineNr">370 </span>  run [
-<span id="L371" class="LineNr">371 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' is waiting for keypress</span>
-<span id="L372" class="LineNr">372 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L373" class="LineNr">373 </span>  <span class="Conceal">¦</span> read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L374" class="LineNr">374 </span>  <span class="Conceal">¦</span> waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L375" class="LineNr">375 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L371" class="LineNr">371 </span>    <span class="Comment"># 'read-move' is waiting for keypress</span>
+<span id="L372" class="LineNr">372 </span>    wait-for-routine-to-block read-move-routine
+<span id="L373" class="LineNr">373 </span>    read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L374" class="LineNr">374 </span>    waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L375" class="LineNr">375 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L376" class="LineNr">376 </span><span class="Constant">F read-move-blocking: routine failed to pause after coming up (before any keys were pressed)]</span>
-<span id="L377" class="LineNr">377 </span>  <span class="Conceal">¦</span> <span class="Comment"># press 'a'</span>
-<span id="L378" class="LineNr">378 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">97/a</span>
-<span id="L379" class="LineNr">379 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L380" class="LineNr">380 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' still waiting for keypress</span>
-<span id="L381" class="LineNr">381 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L382" class="LineNr">382 </span>  <span class="Conceal">¦</span> read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L383" class="LineNr">383 </span>  <span class="Conceal">¦</span> waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L384" class="LineNr">384 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L377" class="LineNr">377 </span>    <span class="Comment"># press 'a'</span>
+<span id="L378" class="LineNr">378 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">97/a</span>
+<span id="L379" class="LineNr">379 </span>    restart read-move-routine
+<span id="L380" class="LineNr">380 </span>    <span class="Comment"># 'read-move' still waiting for keypress</span>
+<span id="L381" class="LineNr">381 </span>    wait-for-routine-to-block read-move-routine
+<span id="L382" class="LineNr">382 </span>    read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L383" class="LineNr">383 </span>    waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L384" class="LineNr">384 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L385" class="LineNr">385 </span><span class="Constant">F read-move-blocking: routine failed to pause after rank 'a']</span>
-<span id="L386" class="LineNr">386 </span>  <span class="Conceal">¦</span> <span class="Comment"># press '2'</span>
-<span id="L387" class="LineNr">387 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">50/'2'</span>
-<span id="L388" class="LineNr">388 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L389" class="LineNr">389 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' still waiting for keypress</span>
-<span id="L390" class="LineNr">390 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L391" class="LineNr">391 </span>  <span class="Conceal">¦</span> read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L392" class="LineNr">392 </span>  <span class="Conceal">¦</span> waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L393" class="LineNr">393 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L386" class="LineNr">386 </span>    <span class="Comment"># press '2'</span>
+<span id="L387" class="LineNr">387 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">50/'2'</span>
+<span id="L388" class="LineNr">388 </span>    restart read-move-routine
+<span id="L389" class="LineNr">389 </span>    <span class="Comment"># 'read-move' still waiting for keypress</span>
+<span id="L390" class="LineNr">390 </span>    wait-for-routine-to-block read-move-routine
+<span id="L391" class="LineNr">391 </span>    read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L392" class="LineNr">392 </span>    waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L393" class="LineNr">393 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L394" class="LineNr">394 </span><span class="Constant">F read-move-blocking: routine failed to pause after file 'a2']</span>
-<span id="L395" class="LineNr">395 </span>  <span class="Conceal">¦</span> <span class="Comment"># press '-'</span>
-<span id="L396" class="LineNr">396 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">45/'-'</span>
-<span id="L397" class="LineNr">397 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L398" class="LineNr">398 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' still waiting for keypress</span>
-<span id="L399" class="LineNr">399 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L400" class="LineNr">400 </span>  <span class="Conceal">¦</span> read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L401" class="LineNr">401 </span>  <span class="Conceal">¦</span> waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L402" class="LineNr">402 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L395" class="LineNr">395 </span>    <span class="Comment"># press '-'</span>
+<span id="L396" class="LineNr">396 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">45/'-'</span>
+<span id="L397" class="LineNr">397 </span>    restart read-move-routine
+<span id="L398" class="LineNr">398 </span>    <span class="Comment"># 'read-move' still waiting for keypress</span>
+<span id="L399" class="LineNr">399 </span>    wait-for-routine-to-block read-move-routine
+<span id="L400" class="LineNr">400 </span>    read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L401" class="LineNr">401 </span>    waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L402" class="LineNr">402 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L403" class="LineNr">403 </span><span class="Constant">F read-move-blocking: routine failed to pause after hyphen 'a2-']</span>
-<span id="L404" class="LineNr">404 </span>  <span class="Conceal">¦</span> <span class="Comment"># press 'a'</span>
-<span id="L405" class="LineNr">405 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">97/a</span>
-<span id="L406" class="LineNr">406 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L407" class="LineNr">407 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' still waiting for keypress</span>
-<span id="L408" class="LineNr">408 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L409" class="LineNr">409 </span>  <span class="Conceal">¦</span> read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L410" class="LineNr">410 </span>  <span class="Conceal">¦</span> waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L411" class="LineNr">411 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L404" class="LineNr">404 </span>    <span class="Comment"># press 'a'</span>
+<span id="L405" class="LineNr">405 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">97/a</span>
+<span id="L406" class="LineNr">406 </span>    restart read-move-routine
+<span id="L407" class="LineNr">407 </span>    <span class="Comment"># 'read-move' still waiting for keypress</span>
+<span id="L408" class="LineNr">408 </span>    wait-for-routine-to-block read-move-routine
+<span id="L409" class="LineNr">409 </span>    read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L410" class="LineNr">410 </span>    waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L411" class="LineNr">411 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L412" class="LineNr">412 </span><span class="Constant">F read-move-blocking: routine failed to pause after rank 'a2-a']</span>
-<span id="L413" class="LineNr">413 </span>  <span class="Conceal">¦</span> <span class="Comment"># press '4'</span>
-<span id="L414" class="LineNr">414 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">52/'4'</span>
-<span id="L415" class="LineNr">415 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L416" class="LineNr">416 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' still waiting for keypress</span>
-<span id="L417" class="LineNr">417 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L418" class="LineNr">418 </span>  <span class="Conceal">¦</span> read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L419" class="LineNr">419 </span>  <span class="Conceal">¦</span> waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L420" class="LineNr">420 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L413" class="LineNr">413 </span>    <span class="Comment"># press '4'</span>
+<span id="L414" class="LineNr">414 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">52/'4'</span>
+<span id="L415" class="LineNr">415 </span>    restart read-move-routine
+<span id="L416" class="LineNr">416 </span>    <span class="Comment"># 'read-move' still waiting for keypress</span>
+<span id="L417" class="LineNr">417 </span>    wait-for-routine-to-block read-move-routine
+<span id="L418" class="LineNr">418 </span>    read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L419" class="LineNr">419 </span>    waiting? <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L420" class="LineNr">420 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L421" class="LineNr">421 </span><span class="Constant">F read-move-blocking: routine failed to pause after file 'a2-a4']</span>
-<span id="L422" class="LineNr">422 </span>  <span class="Conceal">¦</span> <span class="Comment"># press 'newline'</span>
-<span id="L423" class="LineNr">423 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>,<span class="Constant"> 10</span>  <span class="Comment"># newline</span>
-<span id="L424" class="LineNr">424 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L425" class="LineNr">425 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' now completes</span>
-<span id="L426" class="LineNr">426 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L427" class="LineNr">427 </span>  <span class="Conceal">¦</span> read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L428" class="LineNr">428 </span>  <span class="Conceal">¦</span> completed?:bool <span class="Special">&lt;-</span> equal read-move-state, <span class="Constant">1/completed</span>
-<span id="L429" class="LineNr">429 </span>  <span class="Conceal">¦</span> assert completed?, <span class="Constant">[ </span>
+<span id="L422" class="LineNr">422 </span>    <span class="Comment"># press 'newline'</span>
+<span id="L423" class="LineNr">423 </span>    sink <span class="Special">&lt;-</span> write sink,<span class="Constant"> 10</span>  <span class="Comment"># newline</span>
+<span id="L424" class="LineNr">424 </span>    restart read-move-routine
+<span id="L425" class="LineNr">425 </span>    <span class="Comment"># 'read-move' now completes</span>
+<span id="L426" class="LineNr">426 </span>    wait-for-routine-to-block read-move-routine
+<span id="L427" class="LineNr">427 </span>    read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L428" class="LineNr">428 </span>    completed?:bool <span class="Special">&lt;-</span> equal read-move-state, <span class="Constant">1/completed</span>
+<span id="L429" class="LineNr">429 </span>    assert completed?, <span class="Constant">[ </span>
 <span id="L430" class="LineNr">430 </span><span class="Constant">F read-move-blocking: routine failed to terminate on newline]</span>
-<span id="L431" class="LineNr">431 </span>  <span class="Conceal">¦</span> trace<span class="Constant"> 1</span>, <span class="Constant">[test]</span>, <span class="Constant">[reached end]</span>
+<span id="L431" class="LineNr">431 </span>    trace<span class="Constant"> 1</span>, <span class="Constant">[test]</span>, <span class="Constant">[reached end]</span>
 <span id="L432" class="LineNr">432 </span>  ]
 <span id="L433" class="LineNr">433 </span>  trace-should-contain [
-<span id="L434" class="LineNr">434 </span>  <span class="Conceal">¦</span> test: reached end
+<span id="L434" class="LineNr">434 </span>    test: reached end
 <span id="L435" class="LineNr">435 </span>  ]
 <span id="L436" class="LineNr">436 </span>]
 <span id="L437" class="LineNr">437 </span>
 <span id="L438" class="LineNr">438 </span><span class="muScenario">scenario</span> read-move-quit [
 <span id="L439" class="LineNr">439 </span>  <span class="Constant">local-scope</span>
 <span id="L440" class="LineNr">440 </span>  assume-screen <span class="Constant">20/width</span>, <span class="Constant">2/height</span>
-<span id="L441" class="LineNr">441 </span>  <a href='075channel.mu.html#L43'>source</a>:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='075channel.mu.html#L47'>sink</a>:&amp;:<a href='075channel.mu.html#L47'>sink</a>:char <span class="Special">&lt;-</span> <a href='075channel.mu.html#L51'>new-channel</a> <span class="Constant">2/capacity</span>
-<span id="L442" class="LineNr">442 </span>  read-move-routine:num <span class="Special">&lt;-</span> <span class="muControl">start-running</span> <a href='chessboard.mu.html#L248'>read-move</a>, <a href='075channel.mu.html#L43'>source</a>, <a href='081print.mu.html#L16'>screen</a>
+<span id="L441" class="LineNr">441 </span>  source:&amp;:source:char, sink:&amp;:sink:char <span class="Special">&lt;-</span> new-channel <span class="Constant">2/capacity</span>
+<span id="L442" class="LineNr">442 </span>  read-move-routine:num <span class="Special">&lt;-</span> <span class="muControl">start-running</span> read-move, source, screen
 <span id="L443" class="LineNr">443 </span>  run [
-<span id="L444" class="LineNr">444 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' is waiting for keypress</span>
-<span id="L445" class="LineNr">445 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L446" class="LineNr">446 </span>  <span class="Conceal">¦</span> read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L447" class="LineNr">447 </span>  <span class="Conceal">¦</span> waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L448" class="LineNr">448 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L444" class="LineNr">444 </span>    <span class="Comment"># 'read-move' is waiting for keypress</span>
+<span id="L445" class="LineNr">445 </span>    wait-for-routine-to-block read-move-routine
+<span id="L446" class="LineNr">446 </span>    read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L447" class="LineNr">447 </span>    waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L448" class="LineNr">448 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L449" class="LineNr">449 </span><span class="Constant">F read-move-quit: routine failed to pause after coming up (before any keys were pressed)]</span>
-<span id="L450" class="LineNr">450 </span>  <span class="Conceal">¦</span> <span class="Comment"># press 'q'</span>
-<span id="L451" class="LineNr">451 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">113/q</span>
-<span id="L452" class="LineNr">452 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L453" class="LineNr">453 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' completes</span>
-<span id="L454" class="LineNr">454 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L455" class="LineNr">455 </span>  <span class="Conceal">¦</span> read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L456" class="LineNr">456 </span>  <span class="Conceal">¦</span> completed?:bool <span class="Special">&lt;-</span> equal read-move-state, <span class="Constant">1/completed</span>
-<span id="L457" class="LineNr">457 </span>  <span class="Conceal">¦</span> assert completed?, <span class="Constant">[ </span>
+<span id="L450" class="LineNr">450 </span>    <span class="Comment"># press 'q'</span>
+<span id="L451" class="LineNr">451 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">113/q</span>
+<span id="L452" class="LineNr">452 </span>    restart read-move-routine
+<span id="L453" class="LineNr">453 </span>    <span class="Comment"># 'read-move' completes</span>
+<span id="L454" class="LineNr">454 </span>    wait-for-routine-to-block read-move-routine
+<span id="L455" class="LineNr">455 </span>    read-move-state <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L456" class="LineNr">456 </span>    completed?:bool <span class="Special">&lt;-</span> equal read-move-state, <span class="Constant">1/completed</span>
+<span id="L457" class="LineNr">457 </span>    assert completed?, <span class="Constant">[ </span>
 <span id="L458" class="LineNr">458 </span><span class="Constant">F read-move-quit: routine failed to terminate on 'q']</span>
-<span id="L459" class="LineNr">459 </span>  <span class="Conceal">¦</span> trace<span class="Constant"> 1</span>, <span class="Constant">[test]</span>, <span class="Constant">[reached end]</span>
+<span id="L459" class="LineNr">459 </span>    trace<span class="Constant"> 1</span>, <span class="Constant">[test]</span>, <span class="Constant">[reached end]</span>
 <span id="L460" class="LineNr">460 </span>  ]
 <span id="L461" class="LineNr">461 </span>  trace-should-contain [
-<span id="L462" class="LineNr">462 </span>  <span class="Conceal">¦</span> test: reached end
+<span id="L462" class="LineNr">462 </span>    test: reached end
 <span id="L463" class="LineNr">463 </span>  ]
 <span id="L464" class="LineNr">464 </span>]
 <span id="L465" class="LineNr">465 </span>
 <span id="L466" class="LineNr">466 </span><span class="muScenario">scenario</span> read-move-illegal-file [
 <span id="L467" class="LineNr">467 </span>  <span class="Constant">local-scope</span>
 <span id="L468" class="LineNr">468 </span>  assume-screen <span class="Constant">20/width</span>, <span class="Constant">2/height</span>
-<span id="L469" class="LineNr">469 </span>  <a href='075channel.mu.html#L43'>source</a>:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='075channel.mu.html#L47'>sink</a>:&amp;:<a href='075channel.mu.html#L47'>sink</a>:char <span class="Special">&lt;-</span> <a href='075channel.mu.html#L51'>new-channel</a> <span class="Constant">2/capacity</span>
-<span id="L470" class="LineNr">470 </span>  read-move-routine:num <span class="Special">&lt;-</span> <span class="muControl">start-running</span> <a href='chessboard.mu.html#L248'>read-move</a>, <a href='075channel.mu.html#L43'>source</a>, <a href='081print.mu.html#L16'>screen</a>
+<span id="L469" class="LineNr">469 </span>  source:&amp;:source:char, sink:&amp;:sink:char <span class="Special">&lt;-</span> new-channel <span class="Constant">2/capacity</span>
+<span id="L470" class="LineNr">470 </span>  read-move-routine:num <span class="Special">&lt;-</span> <span class="muControl">start-running</span> read-move, source, screen
 <span id="L471" class="LineNr">471 </span>  run [
-<span id="L472" class="LineNr">472 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' is waiting for keypress</span>
-<span id="L473" class="LineNr">473 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L474" class="LineNr">474 </span>  <span class="Conceal">¦</span> read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L475" class="LineNr">475 </span>  <span class="Conceal">¦</span> waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L476" class="LineNr">476 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L472" class="LineNr">472 </span>    <span class="Comment"># 'read-move' is waiting for keypress</span>
+<span id="L473" class="LineNr">473 </span>    wait-for-routine-to-block read-move-routine
+<span id="L474" class="LineNr">474 </span>    read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L475" class="LineNr">475 </span>    waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L476" class="LineNr">476 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L477" class="LineNr">477 </span><span class="Constant">F read-move-illegal-file: routine failed to pause after coming up (before any keys were pressed)]</span>
-<span id="L478" class="LineNr">478 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">50/'2'</span>
-<span id="L479" class="LineNr">479 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L480" class="LineNr">480 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
+<span id="L478" class="LineNr">478 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">50/'2'</span>
+<span id="L479" class="LineNr">479 </span>    restart read-move-routine
+<span id="L480" class="LineNr">480 </span>    wait-for-routine-to-block read-move-routine
 <span id="L481" class="LineNr">481 </span>  ]
 <span id="L482" class="LineNr">482 </span>  screen-should-contain [
-<span id="L483" class="LineNr">483 </span>  <span class="Conceal">¦</span><span class="Constant"> .file too low: 2     .</span>
-<span id="L484" class="LineNr">484 </span>  <span class="Conceal">¦</span><span class="Constant"> .                    .</span>
+<span id="L483" class="LineNr">483 </span>   <span class="Constant"> .file too low: 2     .</span>
+<span id="L484" class="LineNr">484 </span>   <span class="Constant"> .                    .</span>
 <span id="L485" class="LineNr">485 </span>  ]
 <span id="L486" class="LineNr">486 </span>]
 <span id="L487" class="LineNr">487 </span>
 <span id="L488" class="LineNr">488 </span><span class="muScenario">scenario</span> read-move-illegal-rank [
 <span id="L489" class="LineNr">489 </span>  <span class="Constant">local-scope</span>
 <span id="L490" class="LineNr">490 </span>  assume-screen <span class="Constant">20/width</span>, <span class="Constant">2/height</span>
-<span id="L491" class="LineNr">491 </span>  <a href='075channel.mu.html#L43'>source</a>:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='075channel.mu.html#L47'>sink</a>:&amp;:<a href='075channel.mu.html#L47'>sink</a>:char <span class="Special">&lt;-</span> <a href='075channel.mu.html#L51'>new-channel</a> <span class="Constant">2/capacity</span>
-<span id="L492" class="LineNr">492 </span>  read-move-routine:num <span class="Special">&lt;-</span> <span class="muControl">start-running</span> <a href='chessboard.mu.html#L248'>read-move</a>, <a href='075channel.mu.html#L43'>source</a>, <a href='081print.mu.html#L16'>screen</a>
+<span id="L491" class="LineNr">491 </span>  source:&amp;:source:char, sink:&amp;:sink:char <span class="Special">&lt;-</span> new-channel <span class="Constant">2/capacity</span>
+<span id="L492" class="LineNr">492 </span>  read-move-routine:num <span class="Special">&lt;-</span> <span class="muControl">start-running</span> read-move, source, screen
 <span id="L493" class="LineNr">493 </span>  run [
-<span id="L494" class="LineNr">494 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' is waiting for keypress</span>
-<span id="L495" class="LineNr">495 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L496" class="LineNr">496 </span>  <span class="Conceal">¦</span> read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L497" class="LineNr">497 </span>  <span class="Conceal">¦</span> waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L498" class="LineNr">498 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L494" class="LineNr">494 </span>    <span class="Comment"># 'read-move' is waiting for keypress</span>
+<span id="L495" class="LineNr">495 </span>    wait-for-routine-to-block read-move-routine
+<span id="L496" class="LineNr">496 </span>    read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L497" class="LineNr">497 </span>    waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L498" class="LineNr">498 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L499" class="LineNr">499 </span><span class="Constant">F read-move-illegal-rank: routine failed to pause after coming up (before any keys were pressed)]</span>
-<span id="L500" class="LineNr">500 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">97/a</span>
-<span id="L501" class="LineNr">501 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">97/a</span>
-<span id="L502" class="LineNr">502 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L503" class="LineNr">503 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
+<span id="L500" class="LineNr">500 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">97/a</span>
+<span id="L501" class="LineNr">501 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">97/a</span>
+<span id="L502" class="LineNr">502 </span>    restart read-move-routine
+<span id="L503" class="LineNr">503 </span>    wait-for-routine-to-block read-move-routine
 <span id="L504" class="LineNr">504 </span>  ]
 <span id="L505" class="LineNr">505 </span>  screen-should-contain [
-<span id="L506" class="LineNr">506 </span>  <span class="Conceal">¦</span><span class="Constant"> .rank too high: a    .</span>
-<span id="L507" class="LineNr">507 </span>  <span class="Conceal">¦</span><span class="Constant"> .                    .</span>
+<span id="L506" class="LineNr">506 </span>   <span class="Constant"> .rank too high: a    .</span>
+<span id="L507" class="LineNr">507 </span>   <span class="Constant"> .                    .</span>
 <span id="L508" class="LineNr">508 </span>  ]
 <span id="L509" class="LineNr">509 </span>]
 <span id="L510" class="LineNr">510 </span>
 <span id="L511" class="LineNr">511 </span><span class="muScenario">scenario</span> read-move-empty [
 <span id="L512" class="LineNr">512 </span>  <span class="Constant">local-scope</span>
 <span id="L513" class="LineNr">513 </span>  assume-screen <span class="Constant">20/width</span>, <span class="Constant">2/height</span>
-<span id="L514" class="LineNr">514 </span>  <a href='075channel.mu.html#L43'>source</a>:&amp;:<a href='075channel.mu.html#L43'>source</a>:char, <a href='075channel.mu.html#L47'>sink</a>:&amp;:<a href='075channel.mu.html#L47'>sink</a>:char <span class="Special">&lt;-</span> <a href='075channel.mu.html#L51'>new-channel</a> <span class="Constant">2/capacity</span>
-<span id="L515" class="LineNr">515 </span>  read-move-routine:num <span class="Special">&lt;-</span> <span class="muControl">start-running</span> <a href='chessboard.mu.html#L248'>read-move</a>, <a href='075channel.mu.html#L43'>source</a>, <a href='081print.mu.html#L16'>screen</a>
+<span id="L514" class="LineNr">514 </span>  source:&amp;:source:char, sink:&amp;:sink:char <span class="Special">&lt;-</span> new-channel <span class="Constant">2/capacity</span>
+<span id="L515" class="LineNr">515 </span>  read-move-routine:num <span class="Special">&lt;-</span> <span class="muControl">start-running</span> read-move, source, screen
 <span id="L516" class="LineNr">516 </span>  run [
-<span id="L517" class="LineNr">517 </span>  <span class="Conceal">¦</span> <span class="Comment"># 'read-move' is waiting for keypress</span>
-<span id="L518" class="LineNr">518 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
-<span id="L519" class="LineNr">519 </span>  <span class="Conceal">¦</span> read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
-<span id="L520" class="LineNr">520 </span>  <span class="Conceal">¦</span> waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
-<span id="L521" class="LineNr">521 </span>  <span class="Conceal">¦</span> assert waiting?, <span class="Constant">[ </span>
+<span id="L517" class="LineNr">517 </span>    <span class="Comment"># 'read-move' is waiting for keypress</span>
+<span id="L518" class="LineNr">518 </span>    wait-for-routine-to-block read-move-routine
+<span id="L519" class="LineNr">519 </span>    read-move-state:num <span class="Special">&lt;-</span> routine-state read-move-routine
+<span id="L520" class="LineNr">520 </span>    waiting?:bool <span class="Special">&lt;-</span> not-equal read-move-state, <span class="Constant">2/discontinued</span>
+<span id="L521" class="LineNr">521 </span>    assert waiting?, <span class="Constant">[ </span>
 <span id="L522" class="LineNr">522 </span><span class="Constant">F read-move-empty: routine failed to pause after coming up (before any keys were pressed)]</span>
-<span id="L523" class="LineNr">523 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">10/newline</span>
-<span id="L524" class="LineNr">524 </span>  <span class="Conceal">¦</span> <a href='075channel.mu.html#L47'>sink</a> <span class="Special">&lt;-</span> <a href='075channel.mu.html#L67'>write</a> <a href='075channel.mu.html#L47'>sink</a>, <span class="Constant">97/a</span>
-<span id="L525" class="LineNr">525 </span>  <span class="Conceal">¦</span> restart read-move-routine
-<span id="L526" class="LineNr">526 </span>  <span class="Conceal">¦</span> wait-for-routine-to-block read-move-routine
+<span id="L523" class="LineNr">523 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">10/newline</span>
+<span id="L524" class="LineNr">524 </span>    sink <span class="Special">&lt;-</span> write sink, <span class="Constant">97/a</span>
+<span id="L525" class="LineNr">525 </span>    restart read-move-routine
+<span id="L526" class="LineNr">526 </span>    wait-for-routine-to-block read-move-routine
 <span id="L527" class="LineNr">527 </span>  ]
 <span id="L528" class="LineNr">528 </span>  screen-should-contain [
-<span id="L529" class="LineNr">529 </span>  <span class="Conceal">¦</span><span class="Constant"> .that's not enough   .</span>
-<span id="L530" class="LineNr">530 </span>  <span class="Conceal">¦</span><span class="Constant"> .                    .</span>
+<span id="L529" class="LineNr">529 </span>   <span class="Constant"> .that's not enough   .</span>
+<span id="L530" class="LineNr">530 </span>   <span class="Constant"> .                    .</span>
 <span id="L531" class="LineNr">531 </span>  ]
 <span id="L532" class="LineNr">532 </span>]
 <span id="L533" class="LineNr">533 </span>
-<span id="L534" class="LineNr">534 </span><span class="muRecipe">def</span> <a href='chessboard.mu.html#L534'>make-move</a> <a href='chessboard.mu.html#L67'>board</a>:<a href='chessboard.mu.html#L67'>board</a>, m:&amp;:<a href='chessboard.mu.html#L239'>move</a><span class="muRecipe"> -&gt; </span><a href='chessboard.mu.html#L67'>board</a>:<a href='chessboard.mu.html#L67'>board</a> [
+<span id="L534" class="LineNr">534 </span><span class="muRecipe">def</span> make-move board:board, m:&amp;:move<span class="muRecipe"> -&gt; </span>board:board [
 <span id="L535" class="LineNr">535 </span>  <span class="Constant">local-scope</span>
 <span id="L536" class="LineNr">536 </span>  <span class="Constant">load-inputs</span>
 <span id="L537" class="LineNr">537 </span>  from-file:num <span class="Special">&lt;-</span> get *m, <span class="Constant">from-file:offset</span>
@@ -612,26 +611,26 @@ if ('onhashchange' in window) {
 <span id="L548" class="LineNr">548 </span><span class="muScenario">scenario</span> making-a-move [
 <span id="L549" class="LineNr">549 </span>  <span class="Constant">local-scope</span>
 <span id="L550" class="LineNr">550 </span>  assume-screen <span class="Constant">30/width</span>, <span class="Constant">12/height</span>
-<span id="L551" class="LineNr">551 </span>  <a href='chessboard.mu.html#L67'>board</a>:<a href='chessboard.mu.html#L67'>board</a> <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L190'>initial-position</a>
-<span id="L552" class="LineNr">552 </span>  <a href='chessboard.mu.html#L239'>move</a>:&amp;:<a href='chessboard.mu.html#L239'>move</a> <span class="Special">&lt;-</span> new <span class="Constant"><a href='chessboard.mu.html#L239'>move</a>:type</span>
+<span id="L551" class="LineNr">551 </span>  board:board <span class="Special">&lt;-</span> initial-position
+<span id="L552" class="LineNr">552 </span>  move:&amp;:move <span class="Special">&lt;-</span> new <span class="Constant">move:type</span>
 <span id="L553" class="LineNr">553 </span>  *move <span class="Special">&lt;-</span> merge <span class="Constant">6/g</span>, <span class="Constant">1/'2'</span>, <span class="Constant">6/g</span>, <span class="Constant">3/'4'</span>
 <span id="L554" class="LineNr">554 </span>  run [
-<span id="L555" class="LineNr">555 </span>  <span class="Conceal">¦</span> <a href='chessboard.mu.html#L67'>board</a> <span class="Special">&lt;-</span> <a href='chessboard.mu.html#L534'>make-move</a> <a href='chessboard.mu.html#L67'>board</a>, <a href='chessboard.mu.html#L239'>move</a>
-<span id="L556" class="LineNr">556 </span>  <span class="Conceal">¦</span> <a href='081print.mu.html#L16'>screen</a> <span class="Special">&lt;-</span> print <a href='081print.mu.html#L16'>screen</a>, <a href='chessboard.mu.html#L67'>board</a>
+<span id="L555" class="LineNr">555 </span>    board <span class="Special">&lt;-</span> make-move board, move
+<span id="L556" class="LineNr">556 </span>    screen <span class="Special">&lt;-</span> print screen, board
 <span id="L557" class="LineNr">557 </span>  ]
 <span id="L558" class="LineNr">558 </span>  screen-should-contain [
 <span id="L559" class="LineNr">559 </span>  <span class="Comment">#  012345678901234567890123456789</span>
-<span id="L560" class="LineNr">560 </span>  <span class="Conceal">¦</span><span class="Constant"> .8 | r n b q k b n r           .</span>
-<span id="L561" class="LineNr">561 </span>  <span class="Conceal">¦</span><span class="Constant"> .7 | p p p p p p p p           .</span>
-<span id="L562" class="LineNr">562 </span>  <span class="Conceal">¦</span><span class="Constant"> .6 |                           .</span>
-<span id="L563" class="LineNr">563 </span>  <span class="Conceal">¦</span><span class="Constant"> .5 |                           .</span>
-<span id="L564" class="LineNr">564 </span>  <span class="Conceal">¦</span><span class="Constant"> .4 |             P             .</span>
-<span id="L565" class="LineNr">565 </span>  <span class="Conceal">¦</span><span class="Constant"> .3 |                           .</span>
-<span id="L566" class="LineNr">566 </span>  <span class="Conceal">¦</span><span class="Constant"> .2 | P P P P P P   P           .</span>
-<span id="L567" class="LineNr">567 </span>  <span class="Conceal">¦</span><span class="Constant"> .1 | R N B Q K B N R           .</span>
-<span id="L568" class="LineNr">568 </span>  <span class="Conceal">¦</span><span class="Constant"> .  +----------------           .</span>
-<span id="L569" class="LineNr">569 </span>  <span class="Conceal">¦</span><span class="Constant"> .    a b c d e f g h           .</span>
-<span id="L570" class="LineNr">570 </span>  <span class="Conceal">¦</span><span class="Constant"> .                              .</span>
+<span id="L560" class="LineNr">560 </span>   <span class="Constant"> .8 | r n b q k b n r           .</span>
+<span id="L561" class="LineNr">561 </span>   <span class="Constant"> .7 | p p p p p p p p           .</span>
+<span id="L562" class="LineNr">562 </span>   <span class="Constant"> .6 |                           .</span>
+<span id="L563" class="LineNr">563 </span>   <span class="Constant"> .5 |                           .</span>
+<span id="L564" class="LineNr">564 </span>   <span class="Constant"> .4 |             P             .</span>
+<span id="L565" class="LineNr">565 </span>   <span class="Constant"> .3 |                           .</span>
+<span id="L566" class="LineNr">566 </span>   <span class="Constant"> .2 | P P P P P P   P           .</span>
+<span id="L567" class="LineNr">567 </span>   <span class="Constant"> .1 | R N B Q K B N R           .</span>
+<span id="L568" class="LineNr">568 </span>   <span class="Constant"> .  +----------------           .</span>
+<span id="L569" class="LineNr">569 </span>   <span class="Constant"> .    a b c d e f g h           .</span>
+<span id="L570" class="LineNr">570 </span>   <span class="Constant"> .                              .</span>
 <span id="L571" class="LineNr">571 </span>  ]
 <span id="L572" class="LineNr">572 </span>]
 </pre>