/// <summary>
/// Creates a new action by specifying the needed information.
/// </summary>
/// <param name="record">A part of the LALR record from the file content.</param>
/// <param name="states">The LALR states.</param>
/// <param name="symbols">The symbols.</param>
/// <param name="rules">The rules.</param>
/// <returns>A new action object.</returns>
public static Action CreateAction(ActionSubRecord record, StateCollection states, SymbolCollection symbols,
RuleCollection rules)
{
Action action;
switch (record.Action)
{
case 1:
action = CreateShiftAction(record, symbols, states);
break;
case 2:
action = CreateReduceAction(record, symbols, rules);
break;
case 3:
action = CreateGotoAction(record, symbols, states);
break;
case 4:
action = CreateAcceptAction(record, symbols);
break;
default:
return(null); //todo: make exception
}
return(action);
}
private static GotoAction CreateGotoAction(ActionSubRecord record, SymbolCollection symbols,
StateCollection states)
{
SymbolNonterminal symbol = symbols[record.SymbolIndex] as SymbolNonterminal;
State state = states[record.Target];
return new GotoAction(symbol, state);
}
private static GotoAction CreateGotoAction(ActionSubRecord record, SymbolCollection symbols,
StateCollection states)
{
SymbolNonterminal symbol = symbols[record.SymbolIndex] as SymbolNonterminal;
State state = states[record.Target];
return(new GotoAction(symbol, state));
}
private static ShiftAction CreateShiftAction(ActionSubRecord record, SymbolCollection symbols,
StateCollection states)
{
State state = states[record.Target];
SymbolTerminal symbol = symbols[record.SymbolIndex] as SymbolTerminal;
//todo: exception symbol type
return new ShiftAction(symbol, state);
}
/// <summary>
/// Creates a new LALR parser.
/// </summary>
/// <param name="tokenizer">A tokenizer.</param>
/// <param name="states">The LALR states.</param>
/// <param name="startState">The starting state.</param>
/// <param name="symbols"></param>
public LALRParser(IStringTokenizer tokenizer, StateCollection states, State startState, SymbolCollection symbols)
{
this.tokenizer = tokenizer;
this.states = states;
this.startState = startState;
this.symbols = symbols;
storeTokens = StoreTokensMode.NoUserObject;
}
private static ShiftAction CreateShiftAction(ActionSubRecord record, SymbolCollection symbols,
StateCollection states)
{
State state = states[record.Target];
SymbolTerminal symbol = symbols[record.SymbolIndex] as SymbolTerminal;
//todo: exception symbol type
return(new ShiftAction(symbol, state));
}
/// <summary>
/// Creates a new LALR parser.
/// </summary>
/// <param name="tokenizer">A tokenizer.</param>
/// <param name="states">The LALR states.</param>
/// <param name="startState">The starting state.</param>
public LALRParser(IStringTokenizer tokenizer,
StateCollection states,
State startState)
{
this.tokenizer = tokenizer;
this.states = states;
this.startState = startState;
this.trimReductions = trimReductions;
storeTokens = StoreTokensMode.NoUserObject;
}
/// <summary>
/// Creates a new action by specifying the needed information.
/// </summary>
/// <param name="record">A part of the LALR record from the file content.</param>
/// <param name="states">The LALR states.</param>
/// <param name="symbols">The symbols.</param>
/// <param name="rules">The rules.</param>
/// <returns>A new action object.</returns>
public static Action CreateAction(ActionSubRecord record,
StateCollection states,
SymbolCollection symbols,
RuleCollection rules)
{
Action action;
switch (record.Action)
{
case 1: action = CreateShiftAction(record,symbols,states); break;
case 2: action = CreateReduceAction(record,symbols,rules); break;
case 3: action = CreateGotoAction(record,symbols,states); break;
case 4: action = CreateAcceptAction(record,symbols); break;
default: return null; //todo: make exception
}
return action;
}
