86 lines
3.8 KiB
HTML
86 lines
3.8 KiB
HTML
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<!DOCTYPE html>
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<html>
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<!-- Created by GNU Texinfo 7.1, https://www.gnu.org/software/texinfo/ -->
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<!-- This manual documents Guile version 3.0.10.
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Copyright (C) 1996-1997, 2000-2005, 2009-2023 Free Software Foundation,
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Inc.
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Copyright (C) 2021 Maxime Devos
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Copyright (C) 2024 Tomas Volf
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3 or
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any later version published by the Free Software Foundation; with no
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Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
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copy of the license is included in the section entitled "GNU Free
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Documentation License." -->
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<title>About Closure (Guile Reference Manual)</title>
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<meta name="description" content="About Closure (Guile Reference Manual)">
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<meta name="keywords" content="About Closure (Guile Reference Manual)">
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<meta name="Generator" content=".texi2any-real">
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<meta name="viewport" content="width=device-width,initial-scale=1">
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<link href="index.html" rel="start" title="Top">
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<link href="Concept-Index.html" rel="index" title="Concept Index">
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<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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<link href="Hello-Scheme_0021.html" rel="up" title="Hello Scheme!">
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<link href="Further-Reading.html" rel="next" title="Further Reading">
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<link href="About-Expressions.html" rel="prev" title="About Expressions">
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</style>
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<link rel="stylesheet" type="text/css" href="https://www.gnu.org/software/gnulib/manual.css">
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</head>
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<body lang="en">
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<div class="section-level-extent" id="About-Closure">
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<div class="nav-panel">
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<p>
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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>
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</div>
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<hr>
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<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>
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<a class="index-entry-id" id="index-closure"></a>
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<p>The concept of <em class="dfn">closure</em> is the idea that a lambda expression
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“captures” the variable bindings that are in lexical scope at the
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point where the lambda expression occurs. The procedure created by the
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lambda expression can refer to and mutate the captured bindings, and the
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values of those bindings persist between procedure calls.
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</p>
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<p>This section explains and explores the various parts of this idea in
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more detail.
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</p>
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<ul class="mini-toc">
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<li><a href="About-Environments.html" accesskey="1">Names, Locations, Values and Environments</a></li>
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<li><a href="Local-Variables.html" accesskey="2">Local Variables and Environments</a></li>
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<li><a href="Chaining.html" accesskey="3">Environment Chaining</a></li>
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<li><a href="Lexical-Scope.html" accesskey="4">Lexical Scope</a></li>
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<li><a href="Closure.html" accesskey="5">Closure</a></li>
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<li><a href="Serial-Number.html" accesskey="6">Example 1: A Serial Number Generator</a></li>
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<li><a href="Shared-Variable.html" accesskey="7">Example 2: A Shared Persistent Variable</a></li>
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<li><a href="Callback-Closure.html" accesskey="8">Example 3: The Callback Closure Problem</a></li>
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<li><a href="OO-Closure.html" accesskey="9">Example 4: Object Orientation</a></li>
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</ul>
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</div>
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</body>
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</html>
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