t/copy/destruct</a></span>
  <a class="link" href="basic_environment.html#idp51512336-bb"><span class="identifier">basic_environment</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
  <a class="link" href="basic_environment.html#idp51512848-bb"><span class="identifier">basic_environment</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="basic_environment.html" title="Class template basic_environment">basic_envi