about summary refs log tree commit diff stats
path: root/html/same-fringe.mu.html
blob: 6a486e2f9cc600c599007d11c346f51d6fd13a23 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title>Mu - same-fringe.mu</title>
<meta name="Generator" content="Vim/8.0">
<meta name="plugin-version" content="vim7.4_v2">
<meta name="syntax" content="none">
<meta name="settings" content="number_lines,use_css,pre_wrap,no_foldcolumn,expand_tabs,line_ids,prevent_copy=">
<meta name="colorscheme" content="minimal">
<style type="text/css">
<!--
pre { white-space: pre-wrap; font-family: monospace; color: #aaaaaa; background-color: #080808; }
body { font-size: 12pt; font-family: monospace; color: #aaaaaa; background-color: #080808; }
a { color:#eeeeee; text-decoration: none; }
a:hover { text-decoration: underline; }
* { font-size: 12pt; font-size: 1em; }
.muControl { color: #c0a020; }
.muRecipe { color: #ff8700; }
.LineNr { color: #444444; }
.muData { color: #ffff00; }
.Delimiter { color: #800080; }
.Constant { color: #00a0a0; }
.Special { color: #c00000; }
.Comment { color: #9090ff; }
.Comment a { color:#0000ee; text-decoration:underline; }
-->
</style>

<script type='text/javascript'>
<!--

/* function to open any folds containing a jumped-to line before jumping to it */
function JumpToLine()
{
  var lineNum;
  lineNum = window.location.hash;
  lineNum = lineNum.substr(1); /* strip off '#' */

  if (lineNum.indexOf('L') == -1) {
    lineNum = 'L'+lineNum;
  }
  lineElem = document.getElementById(lineNum);
  /* Always jump to new location even if the line was hidden inside a fold, or
   * we corrected the raw number to a line ID.
   */
  if (lineElem) {
    lineElem.scrollIntoView(true);
  }
  return true;
}
if ('onhashchange' in window) {
  window.onhashchange = JumpToLine;
}

-->
</script>
</head>
<body onload='JumpToLine();'>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr"> 1 </span><span class="Comment"># The 'same fringe' problem: <a href="http://wiki.c2.com/?SameFringeProblem">http://wiki.c2.com/?SameFringeProblem</a></span>
<span id="L2" class="LineNr"> 2 </span><span class="Comment"># Example program demonstrating coroutines using Mu's delimited continuations.</span>
<span id="L3" class="LineNr"> 3 </span><span class="Comment">#</span>
<span id="L4" class="LineNr"> 4 </span><span class="Comment"># Expected output:</span>
<span id="L5" class="LineNr"> 5 </span><span class="Comment">#   1</span>
<span id="L6" class="LineNr"> 6 </span><span class="Comment"># (i.e. that the two given trees x and y have the same leaves, in the same</span>
<span id="L7" class="LineNr"> 7 </span><span class="Comment"># order from left to right)</span>
<span id="L8" class="LineNr"> 8 </span>
<span id="L9" class="LineNr"> 9 </span><span class="muData">container</span> <a href='same-fringe.mu.html#L9'>tree</a>:_elem [
<span id="L10" class="LineNr">10 </span>  val:_elem
<span id="L11" class="LineNr">11 </span>  left:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem
<span id="L12" class="LineNr">12 </span>  right:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem
<span id="L13" class="LineNr">13 </span>]
<span id="L14" class="LineNr">14 </span>
<span id="L15" class="LineNr">15 </span><span class="muRecipe">def</span> <a href='same-fringe.mu.html#L15'>main</a> [
<span id="L16" class="LineNr">16 </span>  <span class="Constant">local-scope</span>
<span id="L17" class="LineNr">17 </span>  <span class="Comment"># x: ((a b) c)</span>
<span id="L18" class="LineNr">18 </span>  <span class="Comment"># y: (a (b c))</span>
<span id="L19" class="LineNr">19 </span>  a:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:num <span class="Special">&lt;-</span> new-tree<span class="Constant"> 3</span>
<span id="L20" class="LineNr">20 </span>  b:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:num <span class="Special">&lt;-</span> new-tree<span class="Constant"> 4</span>
<span id="L21" class="LineNr">21 </span>  c:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:num <span class="Special">&lt;-</span> new-tree<span class="Constant"> 5</span>
<span id="L22" class="LineNr">22 </span>  x1:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:num <span class="Special">&lt;-</span> new-tree a, b
<span id="L23" class="LineNr">23 </span>  x:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:num <span class="Special">&lt;-</span> new-tree x1, c
<span id="L24" class="LineNr">24 </span>  y1:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:num <span class="Special">&lt;-</span> new-tree b, c
<span id="L25" class="LineNr">25 </span>  y:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:num <span class="Special">&lt;-</span> new-tree a, y1
<span id="L26" class="LineNr">26 </span>  result:bool <span class="Special">&lt;-</span> <a href='same-fringe.mu.html#L30'>same-fringe</a> x, y
<span id="L27" class="LineNr">27 </span>  $print result <span class="Constant">10/newline</span>
<span id="L28" class="LineNr">28 </span>]
<span id="L29" class="LineNr">29 </span>
<span id="L30" class="LineNr">30 </span><span class="muRecipe">def</span> <a href='same-fringe.mu.html#L30'>same-fringe</a> a:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem, b:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem<span class="muRecipe"> -&gt; </span>result:bool [
<span id="L31" class="LineNr">31 </span>  <span class="Constant">local-scope</span>
<span id="L32" class="LineNr">32 </span>  <span class="Constant">load-inputs</span>
<span id="L33" class="LineNr">33 </span>  k1:continuation <span class="Special">&lt;-</span> <span class="muControl">call-with-continuation-mark</span> <span class="Constant">100/mark</span>, <a href='same-fringe.mu.html#L48'>process</a>, a
<span id="L34" class="LineNr">34 </span>  k2:continuation <span class="Special">&lt;-</span> <span class="muControl">call-with-continuation-mark</span> <span class="Constant">100/mark</span>, <a href='same-fringe.mu.html#L48'>process</a>, b
<span id="L35" class="LineNr">35 </span>  <span class="Delimiter">{</span>
<span id="L36" class="LineNr">36 </span>    k1, x:_elem, a-done?:bool <span class="Special">&lt;-</span> call k1
<span id="L37" class="LineNr">37 </span>    k2, y:_elem, b-done?:bool <span class="Special">&lt;-</span> call k2
<span id="L38" class="LineNr">38 </span>    <span class="muControl">break-if</span> a-done?
<span id="L39" class="LineNr">39 </span>    <span class="muControl">break-if</span> b-done?
<span id="L40" class="LineNr">40 </span>    match?:bool <span class="Special">&lt;-</span> equal x, y
<span id="L41" class="LineNr">41 </span>    <span class="muControl">return-unless</span> match?,<span class="Constant"> false</span>
<span id="L42" class="LineNr">42 </span>   <span class="muControl"> loop</span>
<span id="L43" class="LineNr">43 </span>  <span class="Delimiter">}</span>
<span id="L44" class="LineNr">44 </span>  result <span class="Special">&lt;-</span> and a-done?, b-done?
<span id="L45" class="LineNr">45 </span>]
<span id="L46" class="LineNr">46 </span>
<span id="L47" class="LineNr">47 </span><span class="Comment"># harness around traversal</span>
<span id="L48" class="LineNr">48 </span><span class="muRecipe">def</span> <a href='same-fringe.mu.html#L48'>process</a> t:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem [
<span id="L49" class="LineNr">49 </span>  <span class="Constant">local-scope</span>
<span id="L50" class="LineNr">50 </span>  <span class="Constant">load-inputs</span>
<span id="L51" class="LineNr">51 </span>  <span class="muControl">return-continuation-until-mark</span> <span class="Constant">100/mark</span>  <span class="Comment"># initial</span>
<span id="L52" class="LineNr">52 </span>  <a href='same-fringe.mu.html#L59'>traverse</a> t
<span id="L53" class="LineNr">53 </span>  zero-val:&amp;:_elem <span class="Special">&lt;-</span> new <span class="Constant">_elem:type</span>
<span id="L54" class="LineNr">54 </span>  <span class="muControl">return-continuation-until-mark</span> <span class="Constant">100/mark</span>, *zero-val,<span class="Constant"> true/done</span>  <span class="Comment"># final</span>
<span id="L55" class="LineNr">55 </span>  assert<span class="Constant"> false</span>, <span class="Constant">[continuation called past done]</span>
<span id="L56" class="LineNr">56 </span>]
<span id="L57" class="LineNr">57 </span>
<span id="L58" class="LineNr">58 </span><span class="Comment"># core traversal</span>
<span id="L59" class="LineNr">59 </span><span class="muRecipe">def</span> <a href='same-fringe.mu.html#L59'>traverse</a> t:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem [
<span id="L60" class="LineNr">60 </span>  <span class="Constant">local-scope</span>
<span id="L61" class="LineNr">61 </span>  <span class="Constant">load-inputs</span>
<span id="L62" class="LineNr">62 </span>  <span class="muControl">return-unless</span> t
<span id="L63" class="LineNr">63 </span>  l:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem <span class="Special">&lt;-</span> get *t, <span class="Constant">left:offset</span>
<span id="L64" class="LineNr">64 </span>  <a href='same-fringe.mu.html#L59'>traverse</a> l
<span id="L65" class="LineNr">65 </span>  r:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem <span class="Special">&lt;-</span> get *t, <span class="Constant">right:offset</span>
<span id="L66" class="LineNr">66 </span>  <a href='same-fringe.mu.html#L59'>traverse</a> r
<span id="L67" class="LineNr">67 </span>  <span class="muControl">return-if</span> l
<span id="L68" class="LineNr">68 </span>  <span class="muControl">return-if</span> r
<span id="L69" class="LineNr">69 </span>  <span class="Comment"># leaf</span>
<span id="L70" class="LineNr">70 </span>  v:_elem <span class="Special">&lt;-</span> get *t, <span class="Constant">val:offset</span>
<span id="L71" class="LineNr">71 </span>  <span class="muControl">return-continuation-until-mark</span> <span class="Constant">100/mark</span>, v,<span class="Constant"> false/not-done</span>
<span id="L72" class="LineNr">72 </span>]
<span id="L73" class="LineNr">73 </span>
<span id="L74" class="LineNr">74 </span><span class="Comment"># details</span>
<span id="L75" class="LineNr">75 </span>
<span id="L76" class="LineNr">76 </span><span class="muRecipe">def</span> new-tree x:_elem<span class="muRecipe"> -&gt; </span>result:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem [
<span id="L77" class="LineNr">77 </span>  <span class="Constant">local-scope</span>
<span id="L78" class="LineNr">78 </span>  <span class="Constant">load-inputs</span>
<span id="L79" class="LineNr">79 </span>  result <span class="Special">&lt;-</span> new <span class="Delimiter">{</span>(tree _elem): type<span class="Delimiter">}</span>
<span id="L80" class="LineNr">80 </span>  put *result, <span class="Constant">val:offset</span>, x
<span id="L81" class="LineNr">81 </span>]
<span id="L82" class="LineNr">82 </span>
<span id="L83" class="LineNr">83 </span><span class="muRecipe">def</span> new-tree l:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem, r:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem<span class="muRecipe"> -&gt; </span>result:&amp;:<a href='same-fringe.mu.html#L9'>tree</a>:_elem [
<span id="L84" class="LineNr">84 </span>  <span class="Constant">local-scope</span>
<span id="L85" class="LineNr">85 </span>  <span class="Constant">load-inputs</span>
<span id="L86" class="LineNr">86 </span>  result <span class="Special">&lt;-</span> new <span class="Delimiter">{</span>(tree _elem): type<span class="Delimiter">}</span>
<span id="L87" class="LineNr">87 </span>  put *result, <span class="Constant">left:offset</span>, l
<span id="L88" class="LineNr">88 </span>  put *result, <span class="Constant">right:offset</span>, r
<span id="L89" class="LineNr">89 </span>]
</pre>
</body>
</html>
<!-- vim: set foldmethod=manual : -->