private bool IsTokenExpected(ParsingTableState state, int tokenIndex)
{
if (state.IsNullable)
{
return(true);
}
if (tokenIndex >= _pool.Tokens.Count && !state.IsNullable)
{
return(false);
}
if (tokenIndex >= _pool.Tokens.Count)
{
return(true);
}
var type = _pool.Tokens[tokenIndex].Class == TokenClass.Identifier
? _pool.Identifiers[_pool.Tokens[tokenIndex].Id].Type
: _pool.Tokens[tokenIndex].Id;
return(state.ExpectedTokens.Any(pair => pair.Key == _pool.Tokens[tokenIndex].Class &&
pair.Value.Equals(type)));
}
public static ICollection <ParsingTableState> ParseTransitionsTable(string text)
{
var stateList = new List <ParsingTableState>();
var blockLines = text.Split(Environment.NewLine.ToCharArray(), StringSplitOptions.RemoveEmptyEntries)
.Select(s => s.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries));
foreach (var items in blockLines)
{
if (items.Length == 3)
{
stateList.Last().ExpectedTokens
.Add(new KeyValuePair <TokenClass, int>((TokenClass)int.Parse(items[1]), int.Parse(items[2])));
continue;
}
var state = new ParsingTableState
{
Id = int.Parse(items[0]) - 1,
TransisionStateNumber = int.Parse(items[3]) - 1,
IsAcceptRequired = items[4].Equals("+"),
PushToStack = items[5].Equals("-") ? null : new int?(int.Parse(items[5]) - 1),
IsPopFromStackRequired = items[6].Equals("+"),
IsErrorOccured = items[7].Equals("+"),
IsNullable = items.Length >= 9 && items[8].Equals("!")
};
if (!items[1].Equals("?"))
{
state.ExpectedTokens.Add(new KeyValuePair <TokenClass, int>((TokenClass)int.Parse(items[1]),
int.Parse(items[2])));
}
stateList.Add(state);
}
return(stateList);
}