85 lines
3.8 KiB
HTML
85 lines
3.8 KiB
HTML
<!DOCTYPE html>
|
|
<html>
|
|
<!-- Created by GNU Texinfo 7.1, https://www.gnu.org/software/texinfo/ -->
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<!-- This manual documents Guile version 3.0.10.
|
|
|
|
Copyright (C) 1996-1997, 2000-2005, 2009-2023 Free Software Foundation,
|
|
Inc.
|
|
|
|
Copyright (C) 2021 Maxime Devos
|
|
|
|
Copyright (C) 2024 Tomas Volf
|
|
|
|
|
|
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." -->
|
|
<title>About Closure (Guile Reference Manual)</title>
|
|
|
|
<meta name="description" content="About Closure (Guile Reference Manual)">
|
|
<meta name="keywords" content="About Closure (Guile Reference Manual)">
|
|
<meta name="resource-type" content="document">
|
|
<meta name="distribution" content="global">
|
|
<meta name="Generator" content=".texi2any-real">
|
|
<meta name="viewport" content="width=device-width,initial-scale=1">
|
|
|
|
<link href="index.html" rel="start" title="Top">
|
|
<link href="Concept-Index.html" rel="index" title="Concept Index">
|
|
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
|
|
<link href="Hello-Scheme_0021.html" rel="up" title="Hello Scheme!">
|
|
<link href="Further-Reading.html" rel="next" title="Further Reading">
|
|
<link href="About-Expressions.html" rel="prev" title="About Expressions">
|
|
<style type="text/css">
|
|
<!--
|
|
a.copiable-link {visibility: hidden; text-decoration: none; line-height: 0em}
|
|
span:hover a.copiable-link {visibility: visible}
|
|
-->
|
|
</style>
|
|
<link rel="stylesheet" type="text/css" href="https://www.gnu.org/software/gnulib/manual.css">
|
|
|
|
|
|
</head>
|
|
|
|
<body lang="en">
|
|
<div class="section-level-extent" id="About-Closure">
|
|
<div class="nav-panel">
|
|
<p>
|
|
Next: <a href="Further-Reading.html" accesskey="n" rel="next">Further Reading</a>, Previous: <a href="About-Expressions.html" accesskey="p" rel="prev">Expressions and Evaluation</a>, Up: <a href="Hello-Scheme_0021.html" accesskey="u" rel="up">Hello Scheme!</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
|
|
</div>
|
|
<hr>
|
|
<h3 class="section" id="The-Concept-of-Closure"><span>3.4 The Concept of Closure<a class="copiable-link" href="#The-Concept-of-Closure"> ¶</a></span></h3>
|
|
|
|
<a class="index-entry-id" id="index-closure"></a>
|
|
|
|
<p>The concept of <em class="dfn">closure</em> is the idea that a lambda expression
|
|
“captures” the variable bindings that are in lexical scope at the
|
|
point where the lambda expression occurs. The procedure created by the
|
|
lambda expression can refer to and mutate the captured bindings, and the
|
|
values of those bindings persist between procedure calls.
|
|
</p>
|
|
<p>This section explains and explores the various parts of this idea in
|
|
more detail.
|
|
</p>
|
|
|
|
<ul class="mini-toc">
|
|
<li><a href="About-Environments.html" accesskey="1">Names, Locations, Values and Environments</a></li>
|
|
<li><a href="Local-Variables.html" accesskey="2">Local Variables and Environments</a></li>
|
|
<li><a href="Chaining.html" accesskey="3">Environment Chaining</a></li>
|
|
<li><a href="Lexical-Scope.html" accesskey="4">Lexical Scope</a></li>
|
|
<li><a href="Closure.html" accesskey="5">Closure</a></li>
|
|
<li><a href="Serial-Number.html" accesskey="6">Example 1: A Serial Number Generator</a></li>
|
|
<li><a href="Shared-Variable.html" accesskey="7">Example 2: A Shared Persistent Variable</a></li>
|
|
<li><a href="Callback-Closure.html" accesskey="8">Example 3: The Callback Closure Problem</a></li>
|
|
<li><a href="OO-Closure.html" accesskey="9">Example 4: Object Orientation</a></li>
|
|
</ul>
|
|
</div>
|
|
|
|
|
|
|
|
</body>
|
|
</html>
|