private static bool IsValidDouble(CharacterStream cs, int start, int end)
{
int len = end - start;
string s = cs.GetSubstringAt(start, len);
double n;
return(Double.TryParse(s, NumberStyles.Number | NumberStyles.AllowExponent, CultureInfo.InvariantCulture, out n));
}
private static int Get3CharOrShorterOperatorLength(CharacterStream cs)
{
if (cs.DistanceFromEnd >= 3)
{
string threeLetterCandidate = cs.GetSubstringAt(cs.Position, 3);
if (threeLetterCandidate.Length == 3)
{
int index = Array.BinarySearch <string>(_threeChars, threeLetterCandidate);
if (index >= 0)
{
return(3);
}
}
}
return(Get2CharOrShorterOperatorLength(cs));
}
internal static int Get2CharOrShorterOperatorLength(CharacterStream cs)
{
if (cs.DistanceFromEnd >= 2)
{
string twoLetterCandidate = cs.GetSubstringAt(cs.Position, 2);
if (twoLetterCandidate.Length == 2)
{
int index = Array.BinarySearch <string>(_twoChars, twoLetterCandidate);
if (index >= 0)
{
return(2);
}
}
}
return(GetSingleCharOperatorLength(cs.CurrentChar));
}
