x.html">I</a> : <span class="keyword">sig</span> ... <span class="keyword">end</span></code></div><dl><dt class="spec value" id="val-non_zero_ring"><a href="#val-non_zero_ring" class="anchor"></a><code><span class="keyword">val</span> non_zero_ring : bool</code></dt><dt class="spec value" id="val-multiplicative_inverse"><a href="#val-multiplicative_inverse" class="anchor"></a><code><span class="keyword">val</span> multiplicative_inverse : <a href="../argument-1-D/index.html#type-t">D.t</a> <span>&#45;&gt;</