e type <code><span>Builder.Siso</span></code></h1></header><div class="odoc-content"><div class="odoc-spec"><div class="spec value anchored" id="val-label"><a href="#val-label" class="anchor"></a><code><span><span class="keyword">val</span> label : string</span></code></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-ff_f"><a href="#val-ff_f" class="anchor"></a><code><span><span class="keyword">val</span> ff_f : <span><a href="../../A/index.html#type-elt">A.elt</a> <span class="arr