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<p><span><i>Declarations</i></span> provide a way of specifying information for use by program processors, such as the evaluator or the compiler.</p>
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<p><span><i>Local declarations</i></span> can be embedded in executable code using <span><b>declare</b></span>. <span><i>Global declarations</i></span>, or <span><i>proclamations</i></span>, are established by <span><b>proclaim</b></span> or <span><b>declaim</b></span>.</p>
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<p>The <span><b>the</b></span> <span><i>special form</i></span> provides a shorthand notation for making a <span><i>local declaration</i></span> about the <span><i>type</i></span> of the <span><i>value</i></span> of a given <span><i>form</i></span>.</p>
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<p>The consequences are undefined if a program violates a <span><i>declaration</i></span> or a <span><i>proclamation</i></span>.</p>
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<h2 class="anchor anchorWithStickyNavbar_LWe7" id="331-minimal-declaration-processing-requirements">3.3.1 Minimal Declaration Processing Requirements<a href="d-d-declarations.html#331-minimal-declaration-processing-requirements" class="hash-link" aria-label="Direct link to 3.3.1 Minimal Declaration Processing Requirements" title="Direct link to 3.3.1 Minimal Declaration Processing Requirements"></a></h2>
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<p>In general, an <span><i>implementation</i></span> is free to ignore <span><i>declaration specifiers</i></span> except for the <span><b>declaration</b></span>, <span><b>notinline</b></span>, <strong>safety</strong>, and <span><b>special</b></span> <span><i>declaration specifiers</i></span>.</p>
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<p>A <span><b>declaration</b></span> <span><i>declaration</i></span> must suppress warnings about unrecognized <span><i>declarations</i></span> of the kind that it declares. If an <span><i>implementation</i></span> does not produce warnings about unrecognized declarations, it may safely ignore this <span><i>declaration</i></span>.</p>
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<p>A <span><b>notinline</b></span> <span><i>declaration</i></span> must be recognized by any <span><i>implementation</i></span> that supports inline functions or <span><i>compiler macros</i></span> in order to disable those facilities. An <span><i>implementation</i></span> that does not use inline functions or <span><i>compiler macros</i></span> may safely ignore this <span><i>declaration</i></span>.</p>
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<p>A <strong>safety</strong> <span><i>declaration</i></span> that increases the current safety level must always be recognized. An <span><i>implementation</i></span> that always processes code as if safety were high may safely ignore this <span><i>declaration</i></span>.</p>
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<p>A <span><b>special</b></span> <span><i>declaration</i></span> must be processed by all <span><i>implementations</i></span>.</p>
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<h2 class="anchor anchorWithStickyNavbar_LWe7" id="332-declaration-specifiers">3.3.2 Declaration Specifiers<a href="d-d-declarations.html#332-declaration-specifiers" class="hash-link" aria-label="Direct link to 3.3.2 Declaration Specifiers" title="Direct link to 3.3.2 Declaration Specifiers"></a></h2>
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<p>A <span><i>declaration specifier</i></span> is 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>. It is a <span><i>list</i></span> whose <span><i>car</i></span> is a <span><i>declaration identifier</i></span> , and whose <span><i>cdr</i></span> is data interpreted according to rules specific to the <span><i>declaration identifier</i></span> .</p>
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<h2 class="anchor anchorWithStickyNavbar_LWe7" id="333-declaration-identifiers">3.3.3 Declaration Identifiers<a href="d-d-declarations.html#333-declaration-identifiers" class="hash-link" aria-label="Direct link to 3.3.3 Declaration Identifiers" title="Direct link to 3.3.3 Declaration Identifiers"></a></h2>
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<p>Figure 3–9 shows a list of all <span><i>declaration identifiers</i></span> defined by this standard.</p>
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<p>|</p><p><strong>declaration ignore special</strong> </p><p><strong>dynamic-extent inline type</strong> </p><p><strong>ftype notinline</strong> </p><p><strong>ignorable optimize</strong></p>|<p></p>
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<p>| :- |</p>
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<p><strong>Figure 3–9. Common Lisp Declaration Identifiers</strong></p>
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<p>An implementation is free to support other (<span><i>implementation-defined</i></span>) <span><i>declaration identifiers</i></span> as well. A warning might be issued if a <span><i>declaration identifier</i></span> is not among those defined above, is not defined by the <span><i>implementation</i></span>, is not a <em>type name</em>, and has not been declared in a <span><b>declaration</b></span> <span><i>proclamation</i></span>.</p>
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<h3 class="anchor anchorWithStickyNavbar_LWe7" id="3331-shorthand-notation-for-type-declarations">3.3.3.1 Shorthand notation for Type Declarations<a href="d-d-declarations.html#3331-shorthand-notation-for-type-declarations" class="hash-link" aria-label="Direct link to 3.3.3.1 Shorthand notation for Type Declarations" title="Direct link to 3.3.3.1 Shorthand notation for Type Declarations"></a></h3>
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<p>A <span><i>type specifier</i></span> can be used as a <span><i>declaration identifier</i></span> . (<em>type-specifier {var}</em>*) is taken as shorthand for (type <em>type-specifier {var}</em>*).</p>
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<h2 class="anchor anchorWithStickyNavbar_LWe7" id="334-declaration-scope">3.3.4 Declaration Scope<a href="d-d-declarations.html#334-declaration-scope" class="hash-link" aria-label="Direct link to 3.3.4 Declaration Scope" title="Direct link to 3.3.4 Declaration Scope"></a></h2>
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<p><span><i>Declarations</i></span> can be divided into two kinds: those that apply to the <span><i>bindings</i></span> of <span><i>variables</i></span> or <span><i>functions</i></span>; and those that do not apply to <span><i>bindings</i></span>.</p>
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<p>A <span><i>declaration</i></span> that appears at the head of a binding <span><i>form</i></span> and applies to a <span><i>variable</i></span> or <em>function binding</em> made by that <span><i>form</i></span> is called a <span><i>bound declaration</i></span>; such a <span><i>declaration</i></span> affects both the <span><i>binding</i></span> and any references within the <span><i>scope</i></span> of the <span><i>declaration</i></span>.</p>
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<p><span><i>Declarations</i></span> that are not <span><i>bound declarations</i></span> are called <span><i>free declarations</i></span>.</p>
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<p>A <span><i>free declaration</i></span> in a <em>form F</em>1 that applies to a <span><i>binding</i></span> for a <em>name N established</em> by some <em>form F</em>2 of which <em>F</em>1 is a <span><i>subform</i></span> affects only references to <em>N</em> within <em>F</em>1; it does not to apply to other references to <em>N</em> outside of <em>F</em>1, nor does it affect the manner in which the <span><i>binding</i></span> of <em>N</em> by <em>F</em>2 is <em>established</em>.</p>
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<p><span><i>Declarations</i></span> that do not apply to <span><i>bindings</i></span> can only appear as <span><i>free declarations</i></span>.</p>
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<p>The <span><i>scope</i></span> of a <span><i>bound declaration</i></span> is the same as the <span><i>lexical scope</i></span> of the <span><i>binding</i></span> to which it applies; for <span><i>special variables</i></span>, this means the <span><i>scope</i></span> that the <span><i>binding</i></span> would have had had it been a <span><i>lexical binding</i></span>.</p>
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<p>Unless explicitly stated otherwise, the <span><i>scope</i></span> of a <span><i>free declaration</i></span> includes only the body <span><i>subforms</i></span> of the <span><i>form</i></span> at whose head it appears, and no other <span><i>subforms</i></span>. The <span><i>scope</i></span> of <span><i>free declarations</i></span> specifically does not include <span><i>initialization forms</i></span> for <span><i>bindings</i></span> established by the <span><i>form</i></span> containing the <span><i>declarations</i></span>.</p>
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<p>Some <span><i>iteration forms</i></span> include step, end-test, or result <span><i>subforms</i></span> that are also included in the <span><i>scope</i></span> of <span><i>declarations</i></span> that appear in the <span><i>iteration form</i></span>. Specifically, the <span><i>iteration forms</i></span> and <span><i>subforms</i></span> involved are:</p>
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<p><em>•</em> <span><b>do</b></span>, <span><b>do*</b></span>: <em>step-forms</em>, <em>end-test-form</em>, and <em>result-forms</em>.</p>
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<p><em>•</em> <span><b>dolist</b></span>, <span><b>dotimes</b></span>: <em>result-form</em></p>
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<p><em>•</em> <span><b>do-all-symbols</b></span>, <span><b>do-external-symbols</b></span>, <span><b>do-symbols</b></span>: <em>result-form</em></p>
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<h3 class="anchor anchorWithStickyNavbar_LWe7" id="3341-examples-of-declaration-scope">3.3.4.1 Examples of Declaration Scope<a href="d-d-declarations.html#3341-examples-of-declaration-scope" class="hash-link" aria-label="Direct link to 3.3.4.1 Examples of Declaration Scope" title="Direct link to 3.3.4.1 Examples of Declaration Scope"></a></h3>
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<div class="language-lisp codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-lisp codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token plain">Here is an example illustrating the *scope* of *bound declarations*. </span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">(</span><span class="token keyword" style="color:#00009f">let</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">x</span><span class="token plain"> </span><span class="token number" style="color:#36acaa">1</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">;[1] 1st occurrence of x </span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token declare keyword" style="color:#00009f">declare</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">special</span><span class="token plain"> x</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">;[2] 2nd occurrence of x </span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token keyword" style="color:#00009f">let</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">x</span><span class="token plain"> </span><span class="token number" style="color:#36acaa">2</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">;[3] 3rd occurrence of x </span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token keyword" style="color:#00009f">let</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">old-x</span><span class="token plain"> x</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">;[4] 4th occurrence of x </span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token car">x</span><span class="token plain"> </span><span class="token number" style="color:#36acaa">3</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">;[5] 5th occurrence of x </span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="toke
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