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| <a name="Else-1"></a> |
| <h4 class="subsection">4.2.4 Else</h4> |
| |
| <a name="index-_0023else"></a> |
| <p>The ‘<samp>#else</samp>’ directive can be added to a conditional to provide |
| alternative text to be used if the condition fails. This is what it |
| looks like: |
| </p> |
| <div class="smallexample"> |
| <pre class="smallexample">#if <var>expression</var> |
| <var>text-if-true</var> |
| #else /* Not <var>expression</var> */ |
| <var>text-if-false</var> |
| #endif /* Not <var>expression</var> */ |
| </pre></div> |
| |
| <p>If <var>expression</var> is nonzero, the <var>text-if-true</var> is included and |
| the <var>text-if-false</var> is skipped. If <var>expression</var> is zero, the |
| opposite happens. |
| </p> |
| <p>You can use ‘<samp>#else</samp>’ with ‘<samp>#ifdef</samp>’ and ‘<samp>#ifndef</samp>’, too. |
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