public bool TryMatch(string src, int startIndex, out Token tok)
{
var match = regex.Match(src, startIndex);
if (match.Success)
{
var span = new Span(startIndex, startIndex + match.Length);
if (kind.HasValue())
{
tok = new Token(span, kind, match.Value);
}
else
{
tok = new Token(span, kind);
}
return(true);
}
else
{
tok = null;
return(false);
}
}
