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
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Copyright (C) 2017-2023 David Thompson dthompson2@worcester.edu
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
A copy of the license is included in the section entitled "GNU
Free Documentation License".
A copy of the license is also available from the Free Software
Foundation Web site at http://www.gnu.org/licenses/fdl.html.
* Chickadee: (chickadee). Game programming toolkit for Guile.
The document was typeset with
http://www.texinfo.org/ (GNU Texinfo).
-->
<!-- Created by GNU Texinfo 6.7, http://www.gnu.org/software/texinfo/ -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Live Coding (The Chickadee Game Toolkit)</title>
<meta name="description" content="Live Coding (The Chickadee Game Toolkit)" />
<meta name="keywords" content="Live Coding (The Chickadee Game Toolkit)" />
<meta name="resource-type" content="document" />
<meta name="distribution" content="global" />
<meta name="Generator" content="makeinfo" />
<link href="index.html" rel="start" title="Top" />
<link href="Index.html" rel="index" title="Index" />
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents" />
<link href="index.html" rel="up" title="Top" />
<link href="API-Reference.html" rel="next" title="API Reference" />
<link href="Invoking-chickadee-bundle.html" rel="prev" title="Invoking chickadee bundle" />
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
div.lisp {margin-left: 3.2em}
kbd {font-style: oblique}
pre.display {font-family: inherit}
pre.format {font-family: inherit}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
span.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
ul.no-bullet {list-style: none}
@media (min-width: 1140px) {
body {
margin-left: 14rem;
margin-right: 4rem;
max-width: 52rem;
}
}
@media (min-width: 800px) and (max-width: 1140px) {
body {
margin-left: 6rem;
margin-right: 4rem;
max-width: 52rem;
}
}
@media (max-width: 800px) {
body {
margin: 1rem;
}
}
-->
</style>
<link rel="stylesheet" type="text/css" href="https://dthompson.us/css/dthompson.css" />
</head>
<body lang="en">
<span id="Live-Coding"></span><div class="header">
<p>
Next: <a href="API-Reference.html" accesskey="n" rel="next">API Reference</a>, Previous: <a href="Command-Line-Interface.html" accesskey="p" rel="prev">Command Line Interface</a>, Up: <a href="index.html" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index.html" title="Index" rel="index">Index</a>]</p>
</div>
<hr />
<span id="Live-Coding-1"></span><h2 class="chapter">4 Live Coding</h2>
<p>One of the biggest appeals of any Lisp dialect is the ability to use
the “read-eval-print loop” (REPL for short) to build programs
iteratively and interactively while the program is running. However,
programs that run in an event loop and respond to user input (such as
a game using the Chickadee library!) require special care for this
workflow to be pleasant.
</p>
<p>If you are using the <code>chickadee play</code> command to run your
game, then the <code>--repl</code> or <code>--repl-server</code> arguments are all
you need to get a live coding environment running.
</p>
<p>If, however, you are using <code>run-game</code> to start the game loop then
it’s still fairly easy to hook up a special kind of REPL by yourself.
</p>
<p>First, create a cooperative REPL server (It’s important to use Guile’s
cooperative REPL server instead of the standard REPL server in
<code>(system repl server)</code> to avoid thread synchronization issues).
Then, in the game loop’s update procedure, call
<code>poll-coop-repl-server</code> and pass the REPL object. Here is a
template to follow:
</p>
<div class="lisp">
<pre class="lisp"><span class="syntax-open">(</span><span class="syntax-symbol">use-modules</span> <span class="syntax-open">(</span><span class="syntax-symbol">chickadee</span><span class="syntax-close">)</span>
<span class="syntax-open">(</span><span class="syntax-symbol">system</span> <span class="syntax-symbol">repl</span> <span class="syntax-symbol">coop-server</span><span class="syntax-close">)</span><span class="syntax-close">)</span>
<span class="syntax-open">(</span><span class="syntax-special">define</span> <span class="syntax-symbol">repl</span> <span class="syntax-open">(</span><span class="syntax-symbol">spawn-coop-repl-server</span><span class="syntax-close">)</span><span class="syntax-close">)</span>
<span class="syntax-open">(</span><span class="syntax-special">define</span> <span class="syntax-open">(</span><span class="syntax-symbol">update</span> <span class="syntax-symbol">dt</span><span class="syntax-close">)</span>
<span class="syntax-open">(</span><span class="syntax-symbol">poll-coop-repl-server</span> <span class="syntax-symbol">repl</span><span class="syntax-close">)</span>
<span class="syntax-symbol">...</span><span class="syntax-close">)</span>
<span class="syntax-open">(</span><span class="syntax-symbol">run-game</span> <span class="syntax-keyword">#:update</span> <span class="syntax-symbol">update</span> <span class="syntax-symbol">...</span><span class="syntax-close">)</span>
</pre></div>
<p>To use the REPL, connect to it via port 37146. Telnet will do the
trick, but using the <a href="https://www.nongnu.org/geiser/">Geiser</a>
extension for Emacs is by far the best way to develop at the REPL with
Guile. Use <code>M-x connect-to-guile</code> to connect to the REPL server.
</p>
</body>
</html>
|
