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<pre class="literallayout"><a name="idp56979584-bb"></a><span class="identifier">weak_ptr</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre>
<p>Effects: Constructs an empty <code class="computeroutput"><a class="link" href="weak_ptr.html" title="Class template weak_ptr">weak_ptr</a></code>. Postconditions: use_count() == 0. </p>
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