private void CheckIfTagSequenceValid(int index, params InputSymbolTag[] tags)
{
switch (tags.Length)
{
case 2:
{
InputSymbolTag previous = tags[0];
InputSymbolTag current = tags[1];
if ((previous == InputSymbolTag.Union || previous == InputSymbolTag.OpeningParenthesis) &&
(
current == InputSymbolTag.Union ||
current == InputSymbolTag.KleeneStar ||
current == InputSymbolTag.KleenePlus
))
{
throw new ArgumentException(index == 0 ? errorAtStart + Rules[0] : String.Format(
errorAtChar + Rules[0], index, GetTagsSample()));
}
if ((previous == InputSymbolTag.KleeneStar || previous == InputSymbolTag.KleenePlus) &&
(current == InputSymbolTag.KleeneStar || current == InputSymbolTag.KleenePlus))
{
throw new ArgumentException(index == 0 ? errorAtStart + Rules[1] : String.Format(
errorAtChar + Rules[1], index, GetTagsSample()));
}
if (previous == InputSymbolTag.OpeningParenthesis &&
current == InputSymbolTag.ClosingParenthesis)
{
throw new ArgumentException(index == 0 ? errorAtStart + Rules[2] : String.Format(
errorAtChar + Rules[2], index, GetTagsSample()));
}
} break;
case 3:
{
InputSymbolTag previous2 = tags[0];
InputSymbolTag previous = tags[1];
InputSymbolTag current = tags[2];
if ((previous2 == InputSymbolTag.OpeningParenthesis && previous == InputSymbolTag.ClosingParenthesis) &&
(
current == InputSymbolTag.Union ||
current == InputSymbolTag.KleeneStar ||
current == InputSymbolTag.KleenePlus
))
{
throw new ArgumentException(index == 0 ? errorAtStart + Rules[3] : String.Format(
errorAtChar + Rules[3], index));
}
} break;
}
}
private int CheckReservedSymbolsAt(int i)
{
int count = taggedInput.Count;
bool success = false;
InputSymbolTag previous = default(InputSymbolTag);
if (count > 0)
{
previous = taggedInput[count - 1].Value;
}
InputSymbolTag previous2 = default(InputSymbolTag);
if (count > 1)
{
previous2 = taggedInput[count - 2].Value;
}
// at most one of parallel threads reaches the last lines of action body
try
{
Parallel.For(0, ReservedSymbols.Length, (int n) =>
{
if (input.IndexOf(ReservedSymbols[n].Key, i, Math.Min(ReservedSymbolMaxLength, input.Length - i)) != i)
{
return;
}
var current = ReservedSymbols[n].Value;
if (count > 0)
{
CheckIfTagSequenceValid(i, previous, current);
if (count > 1)
{
CheckIfTagSequenceValid(i, previous2, previous, current);
}
}
else if (current == InputSymbolTag.Union || current == InputSymbolTag.KleeneStar ||
current == InputSymbolTag.KleenePlus || current == InputSymbolTag.ClosingParenthesis)
{
throw new ArgumentException(String.Format(CultureInfo.CurrentCulture,
errorAtStart + Rules[4]));
}
taggedInput.Add(ReservedSymbols[n]);
if (ReservedSymbols[n].Key.Length > 1)
{
i += ReservedSymbols[n].Key.Length - 1;
}
success = true;
});
}
catch (AggregateException e)
{
int exceptionsCount = e.InnerExceptions.Count;
if (exceptionsCount > 1)
{
throw new ArgumentException(String.Format("there are {0} errors, including an {1}",
exceptionsCount, e.InnerException.Message));
}
throw e.InnerException;
}
if (success)
{
return(i);
}
return(-1);
}
