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| <h4 class="subsection">4.2.4 Else</h4> |
| |
| <p><a name="index-g_t_0023else-90"></a>The ‘<samp><span class="samp">#else</span></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: |
| |
| <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> |
| <p class="noindent">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>You can use ‘<samp><span class="samp">#else</span></samp>’ with ‘<samp><span class="samp">#ifdef</span></samp>’ and ‘<samp><span class="samp">#ifndef</span></samp>’, too. |
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