ass="keyword">val</span>&nbsp;mapOr&nbsp;:&nbsp;default:<span class="keywordsign">'</span>b&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;(<span class="keywordsign">'</span>a&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;<span class="keywordsign">'</span>b)&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;<span class="keywordsign">'</span>a&nbsp;<span class="constructor">Bopt</span>.t&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;<span class="keywordsign">'</span>b<br>
&nbsp;&nbsp;<span class="keyw