private TransitionTable(int tokenCount, int stateCount, int productionCount, string[] tokenDescriptions)
{
TokenCount = tokenCount;
StateCount = stateCount;
ProductionCount = productionCount;
m_gotoTable = new int[stateCount, productionCount];
m_shiftTable = new ActionListNode <int> [stateCount, tokenCount + 1];
m_reduceTable = new ActionListNode <int> [stateCount, tokenCount + 1];
m_tokenDescriptions = tokenDescriptions;
}
public IEnumerator <T> GetEnumerator()
{
ActionListNode <T> currentNode = this;
do
{
yield return(currentNode.Value);
currentNode = currentNode.m_nextNode;
} while (currentNode != null);
}
internal static void AppendToLast(ref ActionListNode <T> list, T value)
{
if (list == null)
{
list = new ActionListNode <T>(value);
}
else
{
ActionListNode <T> head = list;
while (head.m_nextNode != null)
{
head = head.m_nextNode;
}
head.Append(new ActionListNode <T>(value));
}
}
public ActionListNode <T> Append(ActionListNode <T> next)
{
m_nextNode = next;
return(m_nextNode);
}
public static TransitionTable Create(LR0Model model, ScannerInfo scannerInfo)
{
CodeContract.RequiresArgumentNotNull(model, "model");
string[] tokenDescriptions = new string[scannerInfo.EndOfStreamTokenIndex + 1];
List <IProduction> nonterminals = new List <IProduction>();
foreach (var production in model.ProductionInfoManager.Productions)
{
if (!production.IsTerminal)
{
var info = model.ProductionInfoManager.GetInfo(production);
info.NonTerminalIndex = nonterminals.Count;
nonterminals.Add(production);
}
else
{
var terminal = (production as Terminal);
string description;
int index;
if (terminal != null)
{
index = terminal.Token.Index;
description = terminal.Token.Description;
}
else
{
index = scannerInfo.EndOfStreamTokenIndex;
description = "$";
}
tokenDescriptions[index] = description;
}
}
//add one null reference to non-terminal list
//for "accept" action in parsing
nonterminals.Add(null);
TransitionTable table = new TransitionTable(scannerInfo.EndOfStreamTokenIndex + 1, model.States.Count, nonterminals.Count, tokenDescriptions);
table.m_nonTerminals = nonterminals.ToArray();
table.m_acceptProductionIndex = nonterminals.Count - 1;
for (int i = 0; i < model.States.Count; i++)
{
var state = model.States[i];
foreach (var edge in state.Edges)
{
var edgeSymbol = model.ProductionInfoManager.Productions[edge.SymbolIndex];
var info = model.ProductionInfoManager.GetInfo(edgeSymbol);
if (edgeSymbol.IsTerminal)
{
//shift
Terminal t = edgeSymbol as Terminal;
int tokenIndex = t == null ? scannerInfo.EndOfStreamTokenIndex : t.Token.Index;
ActionListNode <int> .AppendToLast(ref table.m_shiftTable[i, tokenIndex], edge.TargetStateIndex);
}
else
{
//goto
table.m_gotoTable[i, info.NonTerminalIndex] = edge.TargetStateIndex;
}
}
//lexer states for shifting
if (state.MaxShiftingLexer != null)
{
ActionListNode <int> .AppendToLast(ref table.m_shiftTable[i, table.TokenCount], state.MaxShiftingLexer.Value);
}
//reduces
foreach (var reduce in state.Reduces)
{
Terminal t = reduce.ReduceTerminal as Terminal;
int tokenIndex = t == null ? scannerInfo.EndOfStreamTokenIndex : t.Token.Index;
var info = model.ProductionInfoManager.GetInfo(reduce.ReduceProduction);
ActionListNode <int> .AppendToLast(ref table.m_reduceTable[i, tokenIndex], info.NonTerminalIndex);
}
//lexer states for reducing
if (state.MaxReducingLexer != null)
{
ActionListNode <int> .AppendToLast(ref table.m_reduceTable[i, table.TokenCount], state.MaxReducingLexer.Value);
}
//accepts
if (state.IsAcceptState)
{
ActionListNode <int> .AppendToLast(ref table.m_reduceTable[i, scannerInfo.EndOfStreamTokenIndex], table.m_acceptProductionIndex);
}
}
return(table);
}
