al-current_costs" class="anchor"></a><code><span><span class="keyword">val</span> current_costs : <span><span class="type-var">'a</span> list</span></span></code></div></div><div class="odoc-spec"><div class="spec value" id="val-previous_costs" class="anchored"><a href="#val-previous_costs" class="anchor"></a><code><span><span class="keyword">val</span> previous_costs : <span><span class="type-var">'a</span> list</span></span></code></div></div><div class="odoc-spec"><div class="spec value" id="val-current_