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<title>cl:multiple-value-list</title>
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<hr>
<h1>cl:multiple-value-list</h1>
<hr>
<p>The <nobr>cl:<b>multiple-value-list</b></nobr> macro evaluates a Lisp
expression and returns all values in a list:</p>
<p><div class="box">
<dl>
<dt>(cl:<b>multiple-value-list</b> <i>expr</i>)</dt>
<dd><i>expr</i> - an arbitrary Lisp expression<br>
returns - all values in a list</dd>
</dl>
</div></p>
<pre class="example">
(defmacro <font color="#0000CC">cl:multiple-value-list</font> (expr)
(setq <font color="#AA5500">cl:*multiple-values*</font> nil)
(let ((result (eval expr)))
(if <font color="#AA5500">cl:*multiple-values*</font>
'<font color="#AA5500">*rslt*</font>
`(list ,result))))
</pre>
<p>The <nobr>cl:<b>multiple-value-list</b></nobr> macro first evaluates the
expression. <nobr>If the</nobr> evaluation returned multiple values, the
value of the <a href="../../reference/global-rslt.htm">*rslt*</a> variable
is returned, otherwise the normal Lisp return value is returned in a list of
one element.</p>
<p><nobr>The
<a href="global-multiple-values.htm">cl:*multiple-values*</a></nobr>
variable <nobr>is <a href="../../reference/t.htm"> T </a></nobr>
if evaluating the expression returns multiple values and
<a href="../../reference/nil.htm">NIL</a> with a normal return value.</p>
<p>Examples:</p>
<pre class="example">
(cl:multiple-value-list 1) => (1) <font color="#008844">; cl:*multiple-values* => NIL</font>
<font color="#008844">; *rslt* => [invalid]</font>
(cl:multiple-value-list
(+ 1 1)) => (2) <font color="#008844">; cl:*multiple-values* => NIL</font>
<font color="#008844">; *rslt* => [invalid]</font>
(cl:multiple-value-list
(cl:values 1 2 3)) => (1 2 3) <font color="#008844">; cl:*multiple-values* => T</font>
<font color="#008844">; *rslt* => (1 2 3)</font>
</pre>
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