ass="keyword">type</span>&nbsp;(<span class="keywordsign">'</span>a,&nbsp;<span class="keywordsign">'</span>b,&nbsp;<span class="keywordsign">'</span>c)&nbsp;format&nbsp;=&nbsp;(<span class="keywordsign">'</span>a,&nbsp;<span class="keywordsign">'</span>b,&nbsp;<span class="keywordsign">'</span>c,&nbsp;<span class="keywordsign">'</span>c)&nbsp;<span class="constructor">Pervasives</span>.format4<br>
&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;string_of_format&nbsp;:&nbsp;(<span class="keywordsign">'</s