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<a href="#var-members">Variables</a>  </div>
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<div class="title">Logical<div class="ingroups"><a class="el" href="group__group-concepts.html">Concepts</a></div></div>  </div>
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<div class="contents">
<a name="details" id="details"></a><h2 class="groupheader">Description</h2>
<p>The <code>Logical</code> concept represents types with a truth value. </p>
<p>Intuitively, a <code>Logical</code> is just a <code>bool</code>, or something tha