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
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Copyright (C) 2017-2020 David Thompson davet@gnu.org
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="Kernel.html" rel="up" title="Kernel">
<link href="Math.html" rel="next" title="Math">
<link href="Window-Manipulation.html" rel="prev" title="Window Manipulation">
<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>
Previous: <a href="Window-Manipulation.html" accesskey="p" rel="prev">Window Manipulation</a>, Up: <a href="Kernel.html" accesskey="u" rel="up">Kernel</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><h4 class="subsection">2.1.4 Live Coding</h4>
<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 video game) require special care for this workflow to be pleasant.
Chickadee provides no built-in support for live coding, but it’s
fairly easy to hook up a special kind of REPL 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="example">
<pre class="example">(use-modules (chickadee)
(system repl coop-server))
(define repl (spawn-coop-repl-server))
(define (update dt)
(poll-coop-repl-server repl)
...)
(run-game #:update update ...)
</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>
|
