iate for a set. I.e., match partition classes over key equality rather than individual keys.</p>

<p>This strategy ignores the multiplicity of keys, and only consider whether a key is included in the two trees at all.
E.g., a single element from one tree will be considered a match for any positive number of elements with the same key in
the other tree.</p>

                      </div>
                      <div class="declaration">
                        <h4>Declaration</h4>
                        <div c