public TokenMatch Read(ICharReader Reader)
{
char input;
int? index;
IState currentState;
StringBuilder sb;
IRule reductionRule;
string lastGoodValue = null;
long lastGoodPosition = 0;
IRule lastGoodRule = null;
TokenMatch result;
if (Reader == null)
{
throw new ArgumentNullException("Reader");
}
sb = new StringBuilder();
currentState = states[0];
while (true)
{
if (Reader.EOF)
{
if (lastGoodPosition != 0)
{
break;
}
throw new Exceptions.EndOfStreamException(Reader.Position);
}
else
{
input = Reader.Read();
index = currentState.GetNextStateIndex(input);
}
if (index == null)
{
if (lastGoodPosition != 0)
{
break;
}
throw new InvalidInputException(Reader.Position, input);
}
sb.Append(input);
currentState = states[index.Value];
reductionRule = currentState.Reductions.FirstOrDefault();
if (reductionRule != null)
{
lastGoodPosition = Reader.Position;
lastGoodRule = reductionRule;
lastGoodValue = sb.ToString();
}
}
Reader.Seek(lastGoodPosition);
result = new TokenMatch();
result.Success = true;
result.Token = new Token(lastGoodRule.Name, lastGoodValue);
result.Tags = lastGoodRule.Tags.ToArray();
return(result);
}
