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  <p class="right" id="assertions-1"><span id="index-0"></span><strong>object</strong></p>
<section id="assertions-mode">
<h1><code class="docutils literal notranslate"><span class="pre">assertions(Mode)</span></code><a class="headerlink" href="#assertions-mode" title="Link to this heading"></a></h1>
<p>A simple assertions framework. Can be used as a hook object for either suppressing assertions (<code class="docutils literal notranslate"><span class="pre">production</span></code> mode) or expanding them with file context information (<code class="docutils literal notranslate"><span class="pre">debug</span></code> mode).</p>
<div class="line-block">
<div class="line"><strong>Availability:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">logtalk_load(assertions(loader))</span></code></div>
</div>
</div>
<div class="line-block">
<div class="line"><strong>Author:</strong> Paulo Moura</div>
<div class="line"><strong>Version:</strong> 2:2:2</div>
<div class="line"><strong>Date:</strong> 2022-07-04</div>
</div>
<div class="line-block">
<div class="line"><strong>Compilation flags:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">static,</span> <span class="pre">context_switching_calls</span></code></div>
</div>
</div>
<div class="line-block">
<div class="line"><strong>Implements:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">public</span></code> <a class="reference internal" href="expanding_0.html#expanding-0"><span class="std std-ref">expanding</span></a></div>
</div>
<div class="line"><strong>Uses:</strong></div>
<div class="line-block">
<div class="line"><a class="reference internal" href="logtalk_0.html#logtalk-0"><span class="std std-ref">logtalk</span></a></div>
</div>
</div>
<div class="line-block">
<div class="line"><strong>Remarks:</strong></div>
<div class="line-block">
<div class="line">(none)</div>
</div>
</div>
<div class="line-block">
<div class="line"><strong>Inherited public predicates:</strong></div>
<div class="line-block">
<div class="line"> <a class="reference internal" href="expanding_0.html#expanding-0-goal-expansion-2"><span class="std std-ref">goal_expansion/2</span></a>  <a class="reference internal" href="expanding_0.html#expanding-0-term-expansion-2"><span class="std std-ref">term_expansion/2</span></a></div>
</div>
</div>
<nav class="contents local" id="contents">
<ul class="simple">
<li><p><a class="reference internal" href="#public-predicates" id="id1">Public predicates</a></p>
<ul>
<li><p><a class="reference internal" href="#assertion-1" id="id2"><code class="docutils literal notranslate"><span class="pre">assertion/1</span></code></a></p></li>
<li><p><a class="reference internal" href="#assertion-2" id="id3"><code class="docutils literal notranslate"><span class="pre">assertion/2</span></code></a></p></li>
</ul>
</li>
<li><p><a class="reference internal" href="#protected-predicates" id="id4">Protected predicates</a></p></li>
<li><p><a class="reference internal" href="#private-predicates" id="id5">Private predicates</a></p></li>
<li><p><a class="reference internal" href="#operators" id="id6">Operators</a></p></li>
</ul>
</nav>
<section id="public-predicates">
<h2><a class="toc-backref" href="#contents" role="doc-backlink">Public predicates</a><a class="headerlink" href="#public-predicates" title="Link to this heading"></a></h2>
<section id="assertion-1">
<span id="assertions-1-assertion-1"></span><span id="index-1"></span><h3><a class="toc-backref" href="#contents" role="doc-backlink"><code class="docutils literal notranslate"><span class="pre">assertion/1</span></code></a><a class="headerlink" href="#assertion-1" title="Link to this heading"></a></h3>
<p>Checks that an assertion is true. Uses the structured message printing mechanism for printing the results using a silent message for assertion success and a error message for assertion failure.</p>
<div class="line-block">
<div class="line"><strong>Compilation flags:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">static</span></code></div>
</div>
</div>
<div class="line-block">
<div class="line"><strong>Template:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">assertion(Goal)</span></code></div>
</div>
<div class="line"><strong>Meta-predicate template:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">assertion(0)</span></code></div>
</div>
<div class="line"><strong>Mode and number of proofs:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">assertion(&#64;callable)</span></code> - <code class="docutils literal notranslate"><span class="pre">one</span></code></div>
</div>
</div>
<hr class="docutils" />
</section>
<section id="assertion-2">
<span id="assertions-1-assertion-2"></span><span id="index-2"></span><h3><a class="toc-backref" href="#contents" role="doc-backlink"><code class="docutils literal notranslate"><span class="pre">assertion/2</span></code></a><a class="headerlink" href="#assertion-2" title="Link to this heading"></a></h3>
<p>Checks that an assertion is true. Uses the structured message printing mechanism for printing the results using a silent message for assertion success and a error message for assertion failure. The context argument can be used to e.g. pass location data.</p>
<div class="line-block">
<div class="line"><strong>Compilation flags:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">static</span></code></div>
</div>
</div>
<div class="line-block">
<div class="line"><strong>Template:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">assertion(Context,Goal)</span></code></div>
</div>
<div class="line"><strong>Meta-predicate template:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">assertion(*,0)</span></code></div>
</div>
<div class="line"><strong>Mode and number of proofs:</strong></div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">assertion(&#64;term,&#64;callable)</span></code> - <code class="docutils literal notranslate"><span class="pre">one</span></code></div>
</div>
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<section id="protected-predicates">
<h2><a class="toc-backref" href="#contents" role="doc-backlink">Protected predicates</a><a class="headerlink" href="#protected-predicates" title="Link to this heading"></a></h2>
<p>(no local declarations; see entity ancestors if any)</p>
</section>
<section id="private-predicates">
<h2><a class="toc-backref" href="#contents" role="doc-backlink">Private predicates</a><a class="headerlink" href="#private-predicates" title="Link to this heading"></a></h2>
<p>(no local declarations; see entity ancestors if any)</p>
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<section id="operators">
<h2><a class="toc-backref" href="#contents" role="doc-backlink">Operators</a><a class="headerlink" href="#operators" title="Link to this heading"></a></h2>
<p>(none)</p>
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