public override void Visit(ChannelRestrictions restrictions)
 {
     PopChildren();
     if (restrictions.ChannelNames.Count == 0) {
         Return("");
     } else {
         Return(@" \backslash\{" + Join(", ", restrictions.ChannelNames) + @"\}");
     }
 }
 public virtual void Visit(ChannelRestrictions restrictions)
 {
 }
 void Restriction(out ActionRestrictions ar)
 {
     ar = null; ChannelRestrictions res = new ChannelRestrictions();
     Expect(24);
     if (la.kind == 3) {
     Get();
     res.Add(t.val); SetPos(res, t); res.ParenCount = 0; ar = res;
     } else if (la.kind == 25) {
     Get();
     res.ParenCount = 1;
     Expect(3);
     res.Add(t.val); SetPos(res, t);
     while (la.kind == 11) {
         Get();
         Expect(3);
         res.Add(t.val);
     }
     Expect(26);
     ar = res;
     } else if (la.kind == 6) {
     Get();
     ar = new CustomRestrictions(t.val.Replace(":", "")); SetPos(ar, t);
     } else SynErr(45);
 }