public bool Next()
{
PassWhiteSpace();
if (EndOfInput)
return false;
_currentToken = ParseOperator() ?? ParseNumber();
PassWhiteSpace();
return true;
}
char? Read()
{
var c = _input.Read();
if (c != null)
{
Column++;
}
if (c == null)
_currentToken = new Token(TokenType.End);
return c;
}