span class="arrow">&#45;&gt;</span></span> bool</span></code></div><div class="spec-doc"><p>the implication relation: <code>lhs &lt;= rhs</code> means <code>lhs |- rhs</code></p></div></div></details></div><div class="odoc-spec"><div class="spec value" id="val-join" class="anchored"><a href="#val-join" class="anchor"></a><code><span><span class="keyword">val</span> join : <span><a href="#type-t">t</a> <span class="arrow">&#45;&gt;</span></span> <span><a href="#type-t">t</a> <span class="arrow">&#45;&gt;</sp