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
154
155
156
157
158
159
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta name="robots" content="index,nofollow">
<title>MLtonWorld - MLton Standard ML Compiler (SML Compiler)</title>
<link rel="stylesheet" type="text/css" charset="iso-8859-1" media="all" href="common.css">
<link rel="stylesheet" type="text/css" charset="iso-8859-1" media="screen" href="screen.css">
<link rel="stylesheet" type="text/css" charset="iso-8859-1" media="print" href="print.css">
<link rel="Start" href="Home">
</head>
<body lang="en" dir="ltr">
<script src="http://www.google-analytics.com/urchin.js" type="text/javascript">
</script>
<script type="text/javascript">
_uacct = "UA-833377-1";
urchinTracker();
</script>
<table bgcolor = lightblue cellspacing = 0 style = "border: 0px;" width = 100%>
<tr>
<td style = "
border: 0px;
color: darkblue;
font-size: 150%;
text-align: left;">
<a class = mltona href="Home">MLton 20061025</a>
<td style = "
border: 0px;
font-size: 150%;
text-align: center;
width: 50%;">
MLtonWorld
<td style = "
border: 0px;
text-align: right;">
<table cellspacing = 0 style = "border: 0px">
<tr style = "vertical-align: middle;">
</table>
<tr style = "background-color: white;">
<td colspan = 3
style = "
border: 0px;
font-size:70%;
text-align: right;">
<a href = "Home">Home</a>
<a href = "Index">Index</a>
</table>
<div id="content" lang="en" dir="ltr">
<pre class=code>
<B><FONT COLOR="#5F9EA0">signature</FONT></B> MLTON_WORLD <B><FONT COLOR="#5F9EA0">=</FONT></B>
<B><FONT COLOR="#5F9EA0">sig</FONT></B>
<B><FONT COLOR="#A020F0">datatype</FONT></B> status <B><FONT COLOR="#5F9EA0">=</FONT></B> Clone <B><FONT COLOR="#5F9EA0">|</FONT></B> Original
<B><FONT COLOR="#A020F0">val</FONT></B> load: <B><FONT COLOR="#228B22">string</FONT></B> <B><FONT COLOR="#5F9EA0">-</FONT></B><B><FONT COLOR="#5F9EA0">></FONT></B> 'a
<B><FONT COLOR="#A020F0">val</FONT></B> save: <B><FONT COLOR="#228B22">string</FONT></B> <B><FONT COLOR="#5F9EA0">-</FONT></B><B><FONT COLOR="#5F9EA0">></FONT></B> status
<B><FONT COLOR="#A020F0">val</FONT></B> saveThread: <B><FONT COLOR="#228B22">string</FONT></B> <B><FONT COLOR="#5F9EA0">*</FONT></B> Thread.Runnable.t <B><FONT COLOR="#5F9EA0">-</FONT></B><B><FONT COLOR="#5F9EA0">></FONT></B> <B><FONT COLOR="#228B22">unit</FONT></B>
<B><FONT COLOR="#A020F0">end</FONT></B>
</PRE>
<p>
</p>
<ul>
<li>
<p>
<tt>datatype status</tt>
</p>
</li>
<ul>
specifies whether a world is original or restarted (a clone).
</ul>
<li class="gap">
<p>
<tt>load f</tt>
</p>
</li>
<ul>
loads the saved computation from file <tt>f</tt>.
</ul>
<li class="gap">
<p>
<tt>save f</tt>
</p>
</li>
<ul>
saves the entire state of the computation to the file <tt>f</tt>. The computation can then be restarted at a later time using <tt>World.load</tt> or the <tt>load-world</tt> <a href="RunTimeOptions">runtime option</a>. The call to <tt>save</tt> in the original computation returns <tt>Original</tt> and the call in the restarted world returns <tt>Clone</tt>.
</ul>
<li class="gap">
<p>
<tt>saveThread (f, rt)</tt>
</p>
</li>
<ul>
saves the entire state of the computation to the file <tt>f</tt> that will resume with thread <tt>rt</tt> upon restart.
</ul>
</ul>
<h2 id="head-0f01ed56a1e32a05e5ef96e4d779f34784af9a96">Example</h2>
<p>
Suppose that <tt>save-world.sml</tt> contains the following.
<pre class=code>
<B><FONT COLOR="#A020F0">open</FONT></B> MLton.World
<B><FONT COLOR="#A020F0">val</FONT></B> _ <B><FONT COLOR="#5F9EA0">=</FONT></B>
<B><FONT COLOR="#A020F0">case</FONT></B> save <B><FONT COLOR="#BC8F8F">"world"</FONT></B> <B><FONT COLOR="#A020F0">of</FONT></B>
Original <B><FONT COLOR="#5F9EA0">=</FONT></B><B><FONT COLOR="#5F9EA0">></FONT></B> <B><FONT COLOR="#A020F0">print</FONT></B> <B><FONT COLOR="#BC8F8F">"I am the original\n"</FONT></B>
<B><FONT COLOR="#5F9EA0">|</FONT></B> Clone <B><FONT COLOR="#5F9EA0">=</FONT></B><B><FONT COLOR="#5F9EA0">></FONT></B> <B><FONT COLOR="#A020F0">print</FONT></B> <B><FONT COLOR="#BC8F8F">"I am the clone\n"</FONT></B>
</PRE>
</p>
<p>
Then, if we compile <tt>save-world.sml</tt> and run it, the <tt>Original</tt> branch will execute, and a file named <tt>world</tt> will be created.
<pre>% mlton save-world.sml
% save-world
I am the original
</pre>
</p>
<p>
We can then load <tt>world</tt> using the <tt>load-world</tt> <a href="RunTimeOptions">run time option</a>.
</p>
<pre>% save-world @MLton load-world world --
I am the clone
</pre></div>
<p>
<hr>
Last edited on 2005-12-01 23:17:27 by <span title="ppp-71-139-183-221.dsl.snfc21.pacbell.net"><a href="StephenWeeks">StephenWeeks</a></span>.
</body></html>
|
