RDFSharp.Query.RDFAskQuery.ToString C# (CSharp) Метод

        public override String ToString()
        {
            StringBuilder query = new StringBuilder();

            // ASK
            query.Append("ASK\nWHERE {\n");

            // PATTERN GROUPS
            Boolean printingUnion         = false;
            this.PatternGroups.ForEach(pg => {

                //Current pattern group is set as UNION with the next one
                if (pg.JoinAsUnion) {

                    //Current pattern group IS NOT the last of the query (so UNION keyword must be appended at last)
                    if (!pg.Equals(this.PatternGroups.Last())) {
                         //Begin a new Union block
                         if (!printingUnion) {
                              printingUnion = true;
                              query.Append("\n  {");
                         }
                         query.Append(pg.ToString(2) + "    UNION");
                    }

                    //Current pattern group IS the last of the query (so UNION keyword must not be appended at last)
                    else {
                        //End the Union block
                         if (printingUnion) {
                             printingUnion = false;
                             query.Append(pg.ToString(2));
                             query.Append("  }\n");
                         }
                         else {
                             query.Append(pg.ToString());
                         }
                    }

                }

                //Current pattern group is set as INTERSECT with the next one
                else {
                    //End the Union block
                    if (printingUnion) {
                        printingUnion     = false;
                        query.Append(pg.ToString(2));
                        query.Append("  }\n");
                    }
                    else {
                        query.Append(pg.ToString());
                    }
                }

            });

            query.Append("\n}");
            return query.ToString();
        }