private void DiscardToken()
{
_lookaheadFirst = _lookaheadSecond.Clone();
_lookaheadSecond = _lookaheadThird.Clone();
if (_tokenSequence.Any())
_lookaheadThird = _tokenSequence.Pop();
else
_lookaheadThird = new ErrorToken(TokenType.SequenceTerminator, string.Empty);
}
private void LoadSequenceStack(IList<ErrorToken> tokens)
{
_tokenSequence = new Stack<ErrorToken>();
int count = tokens.Count;
for (int i = count - 1; i >= 0; i--)
{
_tokenSequence.Push(tokens[i]);
}
_lookaheadFirst = tokens.Count >= 1 ? _tokenSequence.Pop() : CreateSequenceTerminator();
_lookaheadSecond = tokens.Count >= 2 ? _tokenSequence.Pop() : CreateSequenceTerminator();
_lookaheadThird = tokens.Count >= 3 ? _tokenSequence.Pop() : CreateSequenceTerminator();
}