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<span id="Data-Types"></span><div class="header">
<p>
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<hr>
<span id="Data-Types-1"></span><h4 class="subsection">14.5.5 Data Types</h4>
<p>Here is the command for data types:
</p>
<dl compact="compact">
<dd><span id="index-deftp"></span>
</dd>
<dt><code>@deftp <var>category</var> <var>name</var> <var>attributes</var>…</code></dt>
<dd><p>The <code>@deftp</code> command is the generic definition command for data
types. The command is written at the beginning of a line and is
followed on the same line by the category, by the name of the type
(which is a word like <code>int</code> or <code>float</code>), and then by names of
attributes of objects of that type. Thus, you could use this command
for describing <code>int</code> or <code>float</code>, in which case you could use
<code>data type</code> as the category. (A data type is a category of
certain objects for purposes of deciding which operations can be
performed on them.)
</p>
<p>In Lisp, for example, <em>pair</em> names a particular data
type, and an object of that type has two slots called the
<small>CAR</small> and the <small>CDR</small>. Here is how you would write the first line
of a definition of <code>pair</code>.
</p>
<div class="example">
<pre class="example">@deftp {Data type} pair car cdr
…
@end deftp
</pre></div>
<p>The template is:
</p>
<div class="example">
<pre class="example">@deftp <var>category</var> <var>name-of-type</var> <var>attributes</var>…
<var>body-of-definition</var>
@end deftp
</pre></div>
<p><code>@deftp</code> creates an entry in the index of data types.
</p></dd>
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