devdocs/elisp/accessing-variables.html


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 <h3 class="section">Accessing Variable Values</h3> <p>The usual way to reference a variable is to write the symbol which names it. See <a href="symbol-forms">Symbol Forms</a>. </p> <p>Occasionally, you may want to reference a variable which is only determined at run time. In that case, you cannot specify the variable name in the text of the program. You can use the <code>symbol-value</code> function to extract the value. </p> <dl> <dt id="symbol-value">Function: <strong>symbol-value</strong> <em>symbol</em>
</dt> <dd>
<p>This function returns the value stored in <var>symbol</var>’s value cell. This is where the variable’s current (dynamic) value is stored. If the variable has no local binding, this is simply its global value. If the variable is void, a <code>void-variable</code> error is signaled. </p> <p>If the variable is lexically bound, the value reported by <code>symbol-value</code> is not necessarily the same as the variable’s lexical value, which is determined by the lexical environment rather than the symbol’s value cell. See <a href="variable-scoping">Variable Scoping</a>. </p> <div class="example"> <pre class="example">(setq abracadabra 5)
     ⇒ 5
</pre>
<pre class="example">(setq foo 9)
     ⇒ 9
</pre>

<pre class="example">;; <span class="roman">Here the symbol <code>abracadabra</code></span>
;;   <span class="roman">is the symbol whose value is examined.</span>
(let ((abracadabra 'foo))
  (symbol-value 'abracadabra))
     ⇒ foo
</pre>

<pre class="example">;; <span class="roman">Here, the value of <code>abracadabra</code>,</span>
;;   <span class="roman">which is <code>foo</code>,</span>
;;   <span class="roman">is the symbol whose value is examined.</span>
(let ((abracadabra 'foo))
  (symbol-value abracadabra))
     ⇒ 9
</pre>

<pre class="example">(symbol-value 'abracadabra)
     ⇒ 5
</pre>
</div> </dd>
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