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#undef [C++ Reference]
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<h2><a name="undef" id="undef">#undef</a></h2>
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The #undef command undefines a previously defined macro variable, such as a
variable defined by a <a href="../preprocessor/define.html" class="wikilink1" title="preprocessor:define">#define</a>.
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Related topics: <a href="../preprocessor/define.html" class="wikilink1" title="preprocessor:define">#define</a>
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