/// <summary> /// Adiciona uma tabela de ação. /// </summary> /// <param name="index"></param> /// <param name="table"></param> private void AddLalrTable(int index, LRActionTable table) { if (!_initialized) { throw new ParserException("Table counts not initialized"); } _LalrTables[index] = table; }
/// <summary> /// Executa parser para o token. /// </summary> /// <param name="token"></param> /// <returns></returns> private ParseResult ParseToken(Token token) { ParseResult result = ParseResult.InternalError; LRActionTable table = _LalrTables[_LalrState]; LRAction action = table.GetActionForSymbol(token.TableIndex); if (action != null) { _haveReduction = false; _outputTokens.Clear(); switch (action.Action) { case Action.Accept: _haveReduction = true; result = ParseResult.Accept; break; case Action.Shift: token.State = _LalrState = action.Value; _tempStack.PushToken(token); result = ParseResult.Shift; break; case Action.Reduce: result = Reduce(_rules[action.Value]); break; } } else { _outputTokens.Clear(); foreach (LRAction a in table.Members) { SymbolType kind = a.Symbol.Kind; if (kind == SymbolType.Terminal || kind == SymbolType.End) { _outputTokens.PushToken(new Token(a.Symbol)); } } result = ParseResult.SyntaxError; } return(result); }
/// <summary> /// Carrega as tabelas da gramática. /// </summary> /// <param name="reader"></param> private void LoadTables(GrammarReader reader) { object obj; int index; while (reader.MoveNext()) { byte id = (byte)reader.RetrieveNext(); switch ((RecordId)id) { case RecordId.Parameters: _parameters["Name"] = (string)reader.RetrieveNext(); _parameters["Version"] = (string)reader.RetrieveNext(); _parameters["Author"] = (string)reader.RetrieveNext(); _parameters["About"] = (string)reader.RetrieveNext(); _caseSensitive = (bool)reader.RetrieveNext(); _startSymbol = (int)reader.RetrieveNext(); break; case RecordId.TableCounts: _symbols = new Symbol[(int)reader.RetrieveNext()]; _charsets = new String[(int)reader.RetrieveNext()]; _rules = new Rule[(int)reader.RetrieveNext()]; _DfaStates = new FAState[(int)reader.RetrieveNext()]; _LalrTables = new LRActionTable[(int)reader.RetrieveNext()]; _initialized = true; break; case RecordId.Initial: _initDfaState = (int)reader.RetrieveNext(); _initLalrState = (int)reader.RetrieveNext(); break; case RecordId.Symbols: index = (int)reader.RetrieveNext(); var name = (string)reader.RetrieveNext(); var kind = (SymbolType)(int)reader.RetrieveNext(); var symbol = new Symbol(index, name, kind); AddSymbol(symbol); break; case RecordId.CharSets: index = (int)reader.RetrieveNext(); var charset = (string)reader.RetrieveNext(); AddCharset(index, charset); break; case RecordId.Rules: index = (int)reader.RetrieveNext(); var head = _symbols[(int)reader.RetrieveNext()]; var rule = new Rule(index, head); reader.RetrieveNext(); while ((obj = reader.RetrieveNext()) != null) { rule.AddItem(_symbols[(int)obj]); } AddRule(rule); break; case RecordId.DFAStates: FAState fastate = new FAState(); index = (int)reader.RetrieveNext(); if ((bool)reader.RetrieveNext()) { fastate.AcceptSymbol = (int)reader.RetrieveNext(); } else { reader.RetrieveNext(); } reader.RetrieveNext(); while (!reader.RetrieveDone()) { var ci = (int)reader.RetrieveNext(); var ti = (int)reader.RetrieveNext(); reader.RetrieveNext(); fastate.AddEdge(_charsets[ci], ti); } AddDfaState(index, fastate); break; case RecordId.LRTables: LRActionTable table = new LRActionTable(); index = (int)reader.RetrieveNext(); reader.RetrieveNext(); while (!reader.RetrieveDone()) { var sid = (int)reader.RetrieveNext(); var action = (int)reader.RetrieveNext(); var tid = (int)reader.RetrieveNext(); reader.RetrieveNext(); table.AddItem(_symbols[sid], (Action)action, tid); } AddLalrTable(index, table); break; case RecordId.Comment: Console.WriteLine("Comment record encountered"); break; default: throw new ParserException("Wrong id for record"); } } }