n problems</p></dd></dl></section><section><header><h2 id="accessors"><a href="#accessors" class="anchor"></a>Accessors</h2></header><dl><dt class="spec value" id="val-get_var_names"><a href="#val-get_var_names" class="anchor"></a><code><span class="keyword">val</span> get_var_names : <a href="index.html#type-t">t</a> <span>&#45;&gt;</span> <span>string list</span></code></dt><dd><p>returns list of all variable names</p></dd></dl></section><section><header><h2 id="constructors"><a href="#constructors" class