href="shared_ptr.html#idp56318192-bb"><span class="identifier">shared_ptr</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">explicit</span> <a class="link" href="shared_ptr.html#idp56319648-bb"><span class="identifier">shared_ptr</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">pointer</span> <span class="special">&amp;</span><span class="special">,</span> 
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