        Strong guarantee. Calls to <code class="computeroutput"><span class="identifier">memory_resource</span><span class="special">::</span><span class="identifier">allocate</span></code>
          may throw.
        </p>
<h6>
<a name="json.ref.boost__json__object.insert_or_assign.h4"></a>
          <span class="phrase"><a name="json.ref.boost__json__object.insert_or_assign.return_value"></a></span><a class="link" href="insert_or_assign.html#json.ref.boost__json__object.insert_or_assign.return_value">Retu