AIMA.Core.Logic.Propositional.Parsing.Ast.UnarySentence.getNegated C# (CSharp) Method

        public Sentence getNegated()
        {
            return negated;
        }

 public override Object visitNotSentence(UnarySentence ns, Object arg)
 {
     List<Symbol> s = (List<Symbol>)arg;
     if (ns.getNegated() is Symbol)
     {
         // do nothing .do NOT add a negated Symbol
     }
     else
     {
         s = SetOps
                 .union(s, (List<Symbol>)ns.getNegated().accept(this, arg));
     }
     return s;
 }