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Node:<a name="Conditional%20Syntax">Conditional Syntax</a>,
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<h3 class="section">Conditional Syntax</h3>
<p>A conditional in the C preprocessor begins with a <dfn>conditional
directive</dfn>: <code>#if</code>, <code>#ifdef</code> or <code>#ifndef</code>.
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<li><a accesskey="1" href="Ifdef.html#Ifdef">Ifdef</a>:
<li><a accesskey="2" href="If.html#If">If</a>:
<li><a accesskey="3" href="Defined.html#Defined">Defined</a>:
<li><a accesskey="4" href="Else.html#Else">Else</a>:
<li><a accesskey="5" href="Elif.html#Elif">Elif</a>:
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