: Boost &lt; 1.70</h1></div></div></div>
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<dt><a href="#compatibility-note">Compatibility note</a></dt>
<dt><a href="#use-case">Use case</a></dt>
<dt><a href="#implementation">Implementation</a></dt>
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<p><em>Thanks to <a href="https://github.com/cstratopoulos">Christos Stratopoulos</a> for this Outcome recipe.</em></p>

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<h3 id="compatibility-note">Compatibility note</h3>

<p>This recipe t