private void HandleSyntaxError(LRActionList actionList, Token read)
{
List <Symbol> expectedSymbols = new List <Symbol>();
for (int i = 0; i < actionList.Count; i++)
{
Symbol actionSymbol = actionList[i];
switch (actionSymbol.Type)
{
case SymbolType.Content:
case SymbolType.End:
case SymbolType.GroupStart:
case SymbolType.GroupEnd:
expectedSymbols.Add(actionSymbol);
break;
}
}
OnSyntaxError(read.EndPosition, read.Data, String.Join(",", expectedSymbols));
}
private void HandleSyntaxError(LRActionList actionList, Token read)
{
List<Symbol> expectedSymbols = new List<Symbol>();
for (int i = 0; i < actionList.Count; i++)
{
Symbol actionSymbol = actionList[i];
switch (actionSymbol.Type)
{
case SymbolType.Content:
case SymbolType.End:
case SymbolType.GroupStart:
case SymbolType.GroupEnd:
expectedSymbols.Add(actionSymbol);
break;
}
}
OnSyntaxError(read.EndPosition, read.Data, String.Join(",", expectedSymbols));
}
public bool Parse(TextReader reader)
{
if (egtDataManager == null)
{
OnNotLoadedError();
return(false);
}
TokenQueueStack inputTokens = new TokenQueueStack();
Stack <Token> tokenStack = new Stack <Token>();
tokenStack.Push(new Token());
Stack <Token> groupStack = new Stack <Token>();
LookAheadBuffer lookAheadBuffer = new LookAheadBuffer(reader);
ushort lalrState = 0;
while (true)
{
if (inputTokens.Count == 0)
{
inputTokens.Push(ProduceToken(groupStack, lookAheadBuffer));
OnTokenRead(inputTokens.Peek());
}
//Runaway group
else if (groupStack.Count != 0)
{
OnGroupError();
return(false); //Error; abort
}
else
{
Token read = inputTokens.Peek();
switch (read.Type)
{
case SymbolType.Noise:
inputTokens.Pop();
break;
case SymbolType.Error:
OnLexicalError(read.EndPosition, read.Data);
return(false); //Error; abort
default:
LRActionList actionList = egtDataManager.GetLRActionList(lalrState);
LRAction parseAction = actionList[read.Symbol];
if (parseAction == null)
{
HandleSyntaxError(actionList, read);
return(false);
}
switch (parseAction.Type)
{
case LRActionType.Accept:
OnCompleted(tokenStack.Peek().Tag);
return(true);
case LRActionType.Shift:
lalrState = parseAction.Value;
read.State = lalrState;
tokenStack.Push(read);
//It now exists on the Token-Stack and must be eliminated from the queue.
inputTokens.Dequeue();
break;
case LRActionType.Reduce:
if (!DoReduction(tokenStack, lookAheadBuffer, ref lalrState, parseAction))
{
return(false);
}
break;
}
break;
}
}
}
}
