E](ExprLang[E]):Option[E]"></a> <span class="permalink"><a href="../../provingground/translation/FreeExpr.html#as[E](implicitl:provingground.translation.ExprLang[E]):Option[E]" title="Permalink"><i class="material-icons"></i></a></span> <span class="modifier_kind"><span class="modifier">abstract </span> <span class="kind">def</span></span> <span class="symbol"><span class="name">as</span><span class="tparams">[<span name="E">E</span>]</span><span class="params">(<span class="implicit">implicit </span><sp