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docSidebarContainer_YfHR"><div class="sidebarViewport_aRkj"><div class="sidebar_njMd"><nav aria-label="Docs sidebar" class="menu thin-scrollbar menu_SIkG"><ul class="theme-doc-sidebar-menu menu__list"><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-1 menu__list-item"><a class="menu__link" href="../index.html">Introduction</a></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-0/intro.html">Contents and Figures</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-1/b-b-scope-purpose-and-history.html">1. Introduction</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-2/c-b-character-syntax.html">2. Syntax</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-3/d-b-evaluation.html">3. Evaluation and Compilation</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-4/e-b-introduction.html">4. Types and Classes</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-5/f-b-generalized-reference.html">5. Data and Control Flow</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-6/g-b-the-loop-facility.html">6. Iteration</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-7/h-b-object-creation-and-initialization.html">7. Objects</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../category/81-structures-dictionary.html">8. Structures</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-9/j-b-condition-system-concepts.html">9. Conditions</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-10/ba-b-symbol-concepts.html">10. Symbols</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-11/bb-b-package-concepts.html">11. Packages</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-12/bc-b-number-concepts.html">12. Numbers</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-13/bd-b-character-concepts.html">13. Characters</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-14/be-b-cons-concepts.html">14. Conses</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-15/bf-b-array-concepts.html">15. Arrays</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-16/bg-b-string-concepts.html">16. Strings</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-17/bh-b-sequence-concepts.html">17. Sequences</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-18/bi-b-hash-table-concepts.html">18. Hash Tables</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-19/bj-b-overview-of-filenames.html">19. Filenames</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-20/ca-b-file-system-concepts.html">20. Files</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-21/cb-b-stream-concepts.html">21. Streams</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-22/cc-b-the-lisp-printer.html">22. Printer</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-23/cd-b-reader-concepts.html">23. Reader</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-24/ce-b-system-construction-concepts.html">24. System Construction</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../chap-25/cf-b-the-external-environment.html">25. External Environment</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../environments.html">26. Environments</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../meta-object-protocol.html">27. Meta Object Protocol</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../data-structures.html">28. Data Structures</a></div></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret" aria-expanded="false" href="../portability/trivial-packages.html">29. Portability</a></div></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-1 menu__list-item"><a class="menu__link" href="../dictionary-entries.html">dictionary-entries</a></li><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item"><div class="menu__list-item-collapsible"><a class="menu__link menu__link--sublist menu__link--sublist-caret menu__link--active" aria-expanded="true" href="intro.html">Glossary</a></div><ul style="display:block;overflow:visible;height:auto" class="menu__list"><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="intro.html">Glossary - Introduction</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a class="menu__link" tabindex="0" href="a.html">A</a></li><li class="theme-doc-sidebar-item-link theme-doc-sidebar-item-link-level-2 menu__list-item"><a 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0l-8.36 7.53c-.34.3-.13.87.33.87H5v7c0 .55.45 1 1 1h3c.55 0 1-.45 1-1z" fill="currentColor"></path></svg></a></li><li class="breadcrumbs__item"><span class="breadcrumbs__link">Glossary</span><meta itemprop="position" content="1"></li><li itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item breadcrumbs__item--active"><span class="breadcrumbs__link" itemprop="name">D</span><meta itemprop="position" content="2"></li></ul></nav><div class="theme-doc-markdown markdown"><header><h1>D</h1></header><p><strong>D</strong></p>
<p><strong>data type</strong> <em>n. Trad.</em> a <span><i>type</i></span>.</p>
<p><strong>debug I/O</strong> <em>n.</em> the <em>bidirectional stream</em> that is the <span><i>value</i></span> of the <span><i>variable</i></span> <strong>*debug-io*</strong>.</p>
<p><strong>debugger</strong> <em>n.</em> a facility that allows the <span><i>user</i></span> to handle a <span><i>condition</i></span> interactively. For example, the <span><i>debugger</i></span> might permit interactive selection of a <span><i>restart</i></span> from among the <em>active restarts</em>, and it might perform additional <span><i>implementation-defined</i></span> services for the purposes of debugging.</p>
<p><span><b>declaration</b></span> <em>n.</em> a <span><i>global declaration</i></span> or <span><i>local declaration</i></span>.</p>
<p><strong>declaration identifier</strong> <em>n.</em> one of the <span><i>symbols</i></span> <span><b>declaration</b></span>, <span><b>dynamic-extent</b></span>, <span><b>ftype</b></span>, <span><b>function</b></span>, <span><b>ignore</b></span>, <span><b>inline</b></span>, <span><b>notinline</b></span>, <span><b>optimize</b></span>, <span><b>special</b></span>, or <span><b>type</b></span>; or a <span><i>symbol</i></span> which is the <span><i>name</i></span> of a <span><i>type</i></span>; or a <span><i>symbol</i></span> which has been <em>declared</em> to be a <span><i>declaration identifier</i></span> by using a <span><b>declaration</b></span> <span><i>declaration</i></span>.</p>
<p><strong>declaration specifier</strong> <em>n.</em> an <span><i>expression</i></span> that can appear at top level of a <span><b>declare</b></span> expression or a <span><b>declaim</b></span> form, or as the argument to <span><b>proclaim</b></span>, and which has a <span><i>car</i></span> which is a <span><i>declaration identifier</i></span> , and which has a <span><i>cdr</i></span> that is data interpreted according to rules specific to the <span><i>declaration identifier</i></span> .</p>
<p><span><b>declare</b></span> <em>v.</em> to <span><i>establish</i></span> a <span><i>declaration</i></span>. See <span><b>declare</b></span>, <span><b>declaim</b></span>, or <span><b>proclaim</b></span>.</p>
<p><strong>decline</strong> <em>v.</em> (of a <span><i>handler</i></span> ) to return normally without having <em>handled</em> the <span><i>condition</i></span> being <em>signaled</em>, permitting the signaling process to continue as if the <span><i>handler</i></span> had not been present.</p>
<p><strong>decoded time</strong> <em>n. absolute time</em>, represented as an ordered series of nine <span><i>objects</i></span> which, taken together, form a description of a point in calendar time, accurate to the nearest second (except that <span><i>leap seconds</i></span> are ignored). See Section 25.1.4.1 (Decoded Time).</p>
<p><strong>default method</strong> <em>n.</em> a <span><i>method</i></span> having no <span><i>parameter specializers</i></span> other than the <span><i>class</i></span> <span><b>t</b></span>. Such a <span><i>method</i></span> is always an <span><i>applicable method</i></span> but might be <em>shadowed</em> <sub>2</sub> by a more specific <span><i>method</i></span>.</p>
<p><strong>defaulted initialization argument list</strong> <em>n.</em> a <span><i>list</i></span> of alternating initialization</p>
<p>argument <span><i>names</i></span> and <span><i>values</i></span> in which unsupplied initialization arguments are</p>
<p>defaulted, used in the protocol for initializing and reinitializing <span><i>instances</i></span> of <em>classes</em>.</p>
<p><strong>define-method-combination arguments lambda list</strong> <em>n.</em> a <span><i>lambda list</i></span> used</p>
<p>by the <!-- -->:arguments<!-- --> option to <span><b>define-method-combination</b></span>. See Section 3.4.10</p>
<p>(Define-method-combination Arguments Lambda Lists).</p>
<p><strong>define-modify-macro lambda list</strong> <em>n.</em> a <span><i>lambda list</i></span> used by <span><b>define-modify-macro</b></span>. See Section 3.4.9 (Define-modify-macro Lambda Lists).</p>
<p><strong>defined name</strong> <em>n.</em> a <span><i>symbol</i></span> the meaning of which is defined by Common Lisp.</p>
<p><strong>defining form</strong> <em>n.</em> a <span><i>form</i></span> that has the side-effect of <em>establishing</em> a definition. “<span><b>defun</b></span> and <span><b>defparameter</b></span> are defining forms.”</p>
<p><strong>defsetf lambda list</strong> <em>n.</em> a <span><i>lambda list</i></span> that is like an <span><i>ordinary lambda list</i></span> except that it does not permit <strong>&amp;aux</strong> and that it permits use of <strong>&amp;environment</strong>. See Section 3.4.7 (Defsetf Lambda Lists).</p>
<p><strong>deftype lambda list</strong> <em>n.</em> a <span><i>lambda list</i></span> that is like a <span><i>macro lambda list</i></span> except that the default <span><i>value</i></span> for unsupplied <span><i>optional parameters</i></span> and <span><i>keyword parameters</i></span> is the <span><i>symbol</i></span> <strong>*</strong> (rather than <span><b>nil</b></span>). See Section 3.4.8 (Deftype Lambda Lists).</p>
<p><strong>denormalized</strong> <em>adj.</em>, <em>ANSI</em>, <em>IEEE</em> (of a <span><i>float</i></span>) conforming to the description of</p>
<p>“denormalized” as described by <em>IEEE Standard for Binary Floating-Point Arithmetic</em>. For example, in an <span><i>implementation</i></span> where the minimum possible exponent was -7 but where 0.001 was a valid mantissa, the number 1.0e-10 might be representable as 0.001e-7 internally even if the <span><i>normalized</i></span> representation would call for it to</p>
<p>be represented instead as 1.0e-10 or 0.1e-9. By their nature, <em>denormalized floats</em> generally have less precision than <em>normalized floats</em>.</p>
<p><strong>derived type</strong> <em>n.</em> a <span><i>type specifier</i></span> which is defined in terms of an expansion into</p>
<p>another <span><i>type specifier</i></span> . <span><b>deftype</b></span> defines <span><i>derived types</i></span>, and there may be other</p>
<p><em>implementation-defined operators</em> which do so as well.</p>
<p><strong>derived type specifier</strong> <em>n.</em> a <span><i>type specifier</i></span> for a <span><i>derived type</i></span>.</p>
<p><strong>designator</strong> <em>n.</em> an <span><i>object</i></span> that denotes another <span><i>object</i></span>. In the dictionary entry for an <span><i>operator</i></span> if a <span><i>parameter</i></span> is described as a <span><i>designator</i></span> for a <span><i>type</i></span>, the description of the <span><i>operator</i></span> is written in a way that assumes that appropriate coercion to that <span><i>type</i></span> has</p>
<p>already occurred; that is, that the <span><i>parameter</i></span> is already of the denoted <span><i>type</i></span>. For more detailed information, see Section 1.4.1.5 (Designators).</p>
<p><strong>destructive</strong> <em>adj.</em> (of an <span><i>operator</i></span> ) capable of modifying some program-visible aspect of one or more <span><i>objects</i></span> that are either explicit <span><i>arguments</i></span> to the <span><i>operator</i></span> or that can be obtained directly or indirectly from the <span><i>global environment</i></span> by the <span><i>operator</i></span> .</p>
<p><strong>destructuring lambda list</strong> <em>n.</em> an <span><i>extended lambda list</i></span> used in <span><b>destructuring-bind</b></span> and nested within <span><i>macro lambda lists</i></span>. See Section 3.4.5 (Destructuring Lambda Lists).</p>
<p><strong>different</strong> <em>adj.</em> not the <span><i>same</i></span> “The strings &quot;FOO&quot; and &quot;foo&quot; are different under <span><b>equal</b></span> but not under <span><b>equalp</b></span>.”</p>
<p><strong>digit</strong> <em>n.</em> (in a <span><i>radix</i></span> ) a <span><i>character</i></span> that is among the possible digits (0 to 9, A to Z, and a to z) and that is defined to have an associated numeric weight as a digit in that <span><i>radix</i></span> . See Section 13.1.4.6 (Digits in a Radix).</p>
<p><strong>dimension</strong> <em>n.</em> 1. a non-negative <em>integer</em> indicating the number of <span><i>objects</i></span> an <span><i>array</i></span> can hold along one axis. If the <span><i>array</i></span> is a <span><i>vector</i></span> with a <span><i>fill pointer</i></span> , the <span><i>fill pointer</i></span> is ignored. “The second dimension of that array is 7.” 2. an axis of an array. “This array has six dimensions.”</p>
<p><strong>direct instance</strong> <em>n.</em> (of a <em>class C</em>) an <span><i>object</i></span> whose <span><i>class</i></span> is <em>C</em> itself, rather than some <span><i>subclass</i></span> of <em>C</em>. “The function <span><b>make-instance</b></span> always returns a direct instance of the class which is (or is named by) its first argument.”</p>
<p><strong>direct subclass</strong> <em>n.</em> (of a <em>class C</em><sub>1</sub>) a <em>class C</em><sub>2</sub>, such that <em>C</em><sub>1</sub> is a <span><i>direct superclass</i></span> of <em>C</em><sub>2</sub>.</p>
<p><strong>direct superclass</strong> <em>n.</em> (of a <em>class C</em><sub>1</sub>) a <em>class C</em><sub>2</sub> which was explicitly designated as a <span><i>superclass</i></span> of <em>C</em><sub>1</sub> in the definition of <em>C</em><sub>1</sub>.</p>
<p><strong>disestablish</strong> <em>v.t.</em> to withdraw the <em>establishment</em> of an <span><i>object</i></span>, a <span><i>binding</i></span>, an <span><i>exit point</i></span>, a <span><i>tag</i></span>, a <span><i>handler</i></span> , a <span><i>restart</i></span>, or an <span><i>environment</i></span>.</p>
<p><strong>disjoint</strong> <em>n.</em> (of <span><i>types</i></span>) having no <span><i>elements</i></span> in common.</p>
<p><strong>dispatching macro character</strong> <em>n.</em> a <span><i>macro character</i></span> that has an associated table that specifies the <span><i>function</i></span> to be called for each <span><i>character</i></span> that is seen following the <span><i>dispatching macro character</i></span> . See the <span><i>function</i></span> <span><b>make-dispatch-macro-character</b></span>.</p>
<p><strong>displaced array</strong> <em>n.</em> an <span><i>array</i></span> which has no storage of its own, but which is instead indirected to the storage of another <span><i>array</i></span>, called its <span><i>target</i></span>, at a specified offset, in such a way that any attempt to <span><i>access</i></span> the <span><i>displaced array</i></span> implicitly references the <em>target array</em>.</p>
<p><strong>distinct</strong> <em>adj.</em> not <span><i>identical</i></span>.</p>
<p><strong>documentation string</strong> <em>n.</em> (in a defining <span><i>form</i></span>) A <em>literal string</em> which because of the context in which it appears (rather than because of some intrinsically observable aspect of the <span><i>string</i></span>) is taken as documentation. In some cases, the <span><i>documentation string</i></span> is saved in such a way that it can later be obtained by supplying either an <span><i>object</i></span>, or by supplying a <span><i>name</i></span> and a “kind” to the <span><i>function</i></span> <strong>documentation</strong>. “The body of code in a <span><b>defmacro</b></span> form can be preceded by a documentation string of kind <span><b>function</b></span>.”</p>
<p><strong>dot</strong> <em>n.</em> the <span><i>standard character</i></span> that is variously called “full stop,” “period,” or “dot” (.). See Figure 25.</p>
<p><strong>dotted list</strong> <em>n.</em> a <span><i>list</i></span> which has a terminating <span><i>atom</i></span> that is not <span><b>nil</b></span>. (An <span><i>atom</i></span> by itself is not a <span><i>dotted list</i></span>, however.)</p>
<p><strong>dotted pair</strong> <em>n.</em> 1. a <span><i>cons</i></span> whose <span><i>cdr</i></span> is a <span><i>non-list</i></span>. 2. any <span><i>cons</i></span>, used to emphasize the use of the <span><i>cons</i></span> as a symmetric data pair.</p>
<p><strong>double float</strong> <em>n.</em> an <span><i>object</i></span> of <span><i>type</i></span> <span><b>double-float</b></span>.</p>
<p><strong>double-quote</strong> <em>n.</em> the <span><i>standard character</i></span> that is variously called “quotation mark” or “double quote” (&quot;). See Figure 25.</p>
<p><strong>dynamic binding</strong> <em>n.</em> a <span><i>binding</i></span> in a <span><i>dynamic environment</i></span>.</p>
<p><strong>dynamic environment</strong> <em>n.</em> that part of an <span><i>environment</i></span> that contains <span><i>bindings</i></span></p>
<p>with <span><i>dynamic extent</i></span>. A <span><i>dynamic environment</i></span> contains, among other things: <span><i>exit points</i></span> established by <span><b>unwind-protect</b></span>, and <span><i>bindings</i></span> of <span><i>dynamic variables</i></span>, <span><i>exit points</i></span> established by <span><b>catch</b></span>, <span><i>condition handlers</i></span>, and <span><i>restarts</i></span>.</p>
<p><strong>dynamic extent</strong> <em>n.</em> an <span><i>extent</i></span> whose duration is bounded by points of <em>establishment</em> and <em>disestablishment</em> within the execution of a particular <span><i>form</i></span>. See <span><i>indefinite extent</i></span>. “Dynamic variable bindings have dynamic extent.”</p>
<p><strong>dynamic scope</strong> <em>n. indefinite scope</em> along with <span><i>dynamic extent</i></span>.</p>
<p><strong>dynamic variable</strong> <em>n.</em> a <span><i>variable</i></span> the <span><i>binding</i></span> for which is in the <span><i>dynamic environment</i></span>. 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