]]:OptRestriction[X,Y]"></a> <span class="permalink"><a href="../../provingground/translation/OptRestriction$.html#subtypRestriction[X[_],Y[_]&gt;:X[_]]:provingground.translation.OptRestriction[X,Y]" title="Permalink"><i class="material-icons"></i></a></span> <span class="modifier_kind"><span class="modifier">implicit </span> <span class="kind">def</span></span> <span class="symbol"><span class="name">subtypRestriction</span><span class="tparams">[<span name="X">X<span class="tparams">[<span name="_">_</