private void PrepareToParse() { Token token = new Token(); token.State = m_initLalrState; token.SetParent(m_symbols[m_startSymbol]); m_tempStack.PushToken(token); }
/// <summary>Produces a reduction.</summary> /// <remarks>Removes as many tokens as members in the rule and pushes a /// non-terminal token.</remarks> private ParseResult Reduce(Rule p_rule) { ParseResult result; Token head; if (m_trimReductions && p_rule.ContainsOneNonTerminal) { // The current rule only consists of a single nonterminal and can be trimmed from the // parse tree. Usually we create a new Reduction, assign it to the Data property // of Head and push it on the stack. However, in this case, the Data property of the // Head will be assigned the Data property of the reduced token (i.e. the only one // on the stack). In this case, to save code, the value popped of the stack is changed // into the head. head = m_tempStack.PopToken(); head.SetParent(p_rule.RuleNonTerminal); result = ParseResult.ReduceEliminated; } else { Reduction reduction = new Reduction(); reduction.ParentRule = p_rule; m_tempStack.PopTokensInto(reduction, p_rule.SymbolCount); head = new Token(); head.Data = reduction; head.SetParent(p_rule.RuleNonTerminal); m_haveReduction = true; result = ParseResult.ReduceNormal; } int index = m_tempStack.PeekToken().State; LRAction action = m_LalrTables[index].GetActionForSymbol(p_rule.RuleNonTerminal.TableIndex); if (action != null) { head.State = m_LalrState = action.Value;; m_tempStack.PushToken(head); } else { throw new ParserException("Action for LALR state is null"); } return(result); }
/// <summary>Produces a reduction.</summary> /// <remarks>Removes as many tokens as members in the rule and pushes a /// non-terminal token.</remarks> private ParseResult Reduce(Rule p_rule) { ParseResult result; Token head; if (m_trimReductions && p_rule.ContainsOneNonTerminal) { // The current rule only consists of a single nonterminal and can be trimmed from the // parse tree. Usually we create a new Reduction, assign it to the Data property // of Head and push it on the stack. However, in this case, the Data property of the // Head will be assigned the Data property of the reduced token (i.e. the only one // on the stack). In this case, to save code, the value popped of the stack is changed // into the head. head = m_tempStack.PopToken(); head.SetParent(p_rule.RuleNonTerminal); result = ParseResult.ReduceEliminated; } else { Reduction reduction = new Reduction(); reduction.ParentRule = p_rule; m_tempStack.PopTokensInto(reduction, p_rule.SymbolCount); head = new Token(); head.Data = reduction; head.SetParent(p_rule.RuleNonTerminal); m_haveReduction = true; result = ParseResult.ReduceNormal; } int index = m_tempStack.PeekToken().State; LRAction action = m_LalrTables[index].GetActionForSymbol(p_rule.RuleNonTerminal.TableIndex); if (action != null) { head.State = m_LalrState = action.Value;; m_tempStack.PushToken(head); } else throw new ParserException("Action for LALR state is null"); return result; }
private void PrepareToParse() { Token token = new Token(); token.State = m_initLalrState; token.SetParent(m_symbols[m_startSymbol]); m_tempStack.PushToken(token); }