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  <p class="align-right"><strong>built-in predicate</strong></p>
<section id="threaded-once-1-2">
<span id="predicates-threaded-once-1-2"></span><span id="index-0"></span><h1><code class="docutils literal notranslate"><span class="pre">threaded_once/1-2</span></code><a class="headerlink" href="#threaded-once-1-2" title="Link to this heading"></a></h1>
<section id="description">
<h2>Description<a class="headerlink" href="#description" title="Link to this heading"></a></h2>
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