p;&nbsp;<span class="keyword">val</span>&nbsp;string_of_bool&nbsp;:&nbsp;bool&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;string<br>
&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;bool_of_string&nbsp;:&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;bool<br>
&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;string_of_int&nbsp;:&nbsp;int&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;string<br>
&nbsp;&nbsp;<span class="keyword">external</span>&nbsp;int_of_string&nbsp;:&nbsp;string&nbsp