ybe">Maybe</a> a</li><li class="src short"><a href="#v:isConst">isConst</a> :: <a href="Expr.html#t:Desc" title="Expr">Desc</a> -&gt; <a href="../base-4.11.1.0/Data-Bool.html#t:Bool" title="Data.Bool">Bool</a></li><li class="src short"><a href="#v:assertArgs1">assertArgs1</a> :: <a href="../base-4.11.1.0/Data-String.html#t:String" title="Data.String">String</a> -&gt; [<a href="Expr.html#t:AnyExpr" title="Expr">AnyExpr</a>] -&gt; <a href="../base-4.11.1.0/Data-Either.html#t:Either" title="Data.Either">Either