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<title>environment::variable-exists Function</title>
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v0.92</td>
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<h1>environment::variable-exists</h1>
<p> Gets a value indicating whether the specified environment variable exists. </p>
<h3>Usage</h3>
<code>bool environment::variable-exists(<span class="parameter">name</span>)
</code>
<p />
<h3>Parameters</h3>
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<th>Name</th>
<th>Type</th>
<th>Description</th>
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<td>name</td>
<td>string</td>
<td>The environment variable that should be checked.</td>
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<h3>Return Value</h3>
<b>true</b> if the environment variable exists; otherwise, <b>false</b>. <h3>Examples</h3><ul class="examples"><li><p> Execute a set of tasks only if the "BUILD_DEBUG" environment variable is set. </p><pre class="code">
<if test="${environment::variable-exists('BUILD_DEBUG')}">
...
</if>
</pre></li></ul><h3>Requirements</h3><div style="margin-left: 20px;"><b>Assembly:</b> NAnt.Core (0.92.4543.0)
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