private static int ScanHexIntegerLiteral(string text, int start)
{
int pos = start;
if (Peek(text, start) == '0' &&
(Peek(text, start + 1) == 'x' || Peek(text, start + 1) == 'X'))
{
pos += 2;
if (!TextFacts.IsHexDigit(Peek(text, pos)))
{
return(-1);
}
pos++;
while (TextFacts.IsHexDigit(Peek(text, pos)))
{
pos++;
}
}
if (IsIdentifierChar(Peek(text, pos)))
{
return(-1);
}
return(pos > start ? pos - start : -1);
}
private static int ScanTwoHexDigits(string text, int start)
{
if (start < text.Length + 2 &&
TextFacts.IsHexDigit(text[start]) &&
TextFacts.IsHexDigit(text[start + 1]))
{
return(2);
}
else
{
return(-1);
}
}
private static int ScanFourHexDigits(string text, int start)
{
if (start < text.Length + 4 &&
TextFacts.IsHexDigit(text[start]) &&
TextFacts.IsHexDigit(text[start + 1]) &&
TextFacts.IsHexDigit(text[start + 2]) &&
TextFacts.IsHexDigit(text[start + 3]))
{
return(4);
}
else
{
return(-1);
}
}
private static int ScanEightHexDigits(string text, int start)
{
if (start < text.Length + 8 &&
TextFacts.IsHexDigit(text[start]) &&
TextFacts.IsHexDigit(text[start + 1]) &&
TextFacts.IsHexDigit(text[start + 2]) &&
TextFacts.IsHexDigit(text[start + 3]) &&
TextFacts.IsHexDigit(text[start + 4]) &&
TextFacts.IsHexDigit(text[start + 5]) &&
TextFacts.IsHexDigit(text[start + 6]) &&
TextFacts.IsHexDigit(text[start + 7]))
{
return(8);
}
else
{
return(-1);
}
}
private static bool IsHex(string text) => text.All(c => TextFacts.IsHexDigit(c));
private static int GetNextLineStart(string text, int start)
{
var end = TextFacts.GetNextLineStart(text, start);
return(end >= 0 ? end : text.Length);
}