public static string PeekIdentifier(this IPreprocessorReader rdr)
{
var first = true;
return(rdr.PeekUntil(ch =>
{
if (first)
{
first = false;
return ch.IsWordChar(true);
}
else
{
return ch.IsWordChar(false);
}
}));
}
public static string PeekToken(this IPreprocessorReader rdr, bool stayOnSameLine)
{
bool lineChange;
if (rdr.IgnoreComments(out lineChange))
{
if (lineChange && stayOnSameLine)
{
return(null);
}
return(string.Empty);
}
var ch = rdr.Peek();
if ((ch == '\r' || ch == '\n') && stayOnSameLine)
{
return(null);
}
if (ch == ' ' || ch == '\t')
{
return(rdr.PeekUntil(c => c == ' ' || c == '\t'));
}
if (ch.IsWordChar(true))
{
return(rdr.PeekIdentifier());
}
if (char.IsDigit(ch))
{
var gotDecimal = false;
return(rdr.PeekUntil(c =>
{
if (char.IsDigit(c))
{
return true;
}
if (c == '.')
{
if (gotDecimal)
{
return false;
}
gotDecimal = true;
return true;
}
return false;
}));
}
if (ch == '\"' || ch == '\'')
{
var sb = new StringBuilder();
var lastCh = '\0';
var first = true;
var gotEnd = false;
sb.Append(rdr.PeekUntil(c =>
{
if (gotEnd)
{
return(false);
}
if (first)
{
first = false;
return(true);
}
if (c == ch && lastCh != '\\')
{
gotEnd = true;
return(true);
}
if (c == '\\' && lastCh == '\\')
{
lastCh = '\0';
}
else
{
lastCh = c;
}
return(true);
}));
return(sb.ToString());
}
if (ch == '#')
{
var index = -1;
return(rdr.PeekUntil(c =>
{
index++;
if (index == 0)
{
return c == '#';
}
else if (index == 1)
{
return c.IsWordChar(true);
}
else
{
return c.IsWordChar(false);
}
}));
}
return(ch.ToString());
}