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<span id="Return-Values"></span><div class="header">
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<span id="Return-Values-1"></span><h4 class="subsection">3.1.7 Return Values</h4>
<p>Ordinarily the result of calling a <i>function</i> is a single <i>object</i>.
Sometimes, however, it is convenient for a function to compute several
<i>objects</i> and return them.
</p>
<p>In order to receive other than exactly one value from a <i>form</i>,
one of several <i>special forms</i> or <i>macros</i> must be used to request those
values. If a <i>form</i> produces <i>multiple values</i> which were not
requested in this way, then the first value is given to the caller and
all others are discarded; if the <i>form</i> produces zero values,
then the caller receives <b>nil</b> as a value.
</p>
<p>Figure 3–5 lists
some <i>operators</i> for receiving <i>multiple values</i>_2.
These <i>operators</i> can be used to specify
one or more <i>forms</i> to <i>evaluate</i>
and where to put the <i>values</i> returned by those <i>forms</i>.
</p>
<div class="format">
<pre class="format"> multiple-value-bind multiple-value-prog1 return-from <!-- /@w -->
multiple-value-call multiple-value-setq throw <!-- /@w -->
multiple-value-list return <!-- /@w -->
Figure 3–5: Some operators applicable to receiving multiple values<!-- /@w -->
</pre></div>
<p>The <i>function</i> <b>values</b> can produce <i>multiple values</i>_2.
<tt>(values)</tt> returns zero values;
<tt>(values <i>form</i>)</tt> returns the <i>primary value</i> returned by <i>form</i>;
<tt>(values <i>form1</i> <i>form2</i>)</tt> returns two values,
the <i>primary value</i> of <i>form1</i>
and the <i>primary value</i> of <i>form2</i>;
and so on.
</p>
<p>See <b>multiple-values-limit</b> and <b>values-list</b>.
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