System.Text.RegularExpressions.RegexParser.IsTrueQuantifier C# (CSharp) Method

        internal bool IsTrueQuantifier()
        {
            int nChars = CharsRight();
            if (nChars == 0)
                return false;
            int startpos = Textpos();
            char ch = CharAt(startpos);
            if (ch != '{')
                return ch <= '{' && _category[ch] >= Q;
            int pos = startpos;
            while (--nChars > 0 && (ch = CharAt(++pos)) >= '0' && ch <= '9') ;
            if (nChars == 0 || pos - startpos == 1)
                return false;
            if (ch == '}')
                return true;
            if (ch != ',')
                return false;
            while (--nChars > 0 && (ch = CharAt(++pos)) >= '0' && ch <= '9') ;
            return nChars > 0 && ch == '}';
        }