Exemplo n.º 1
0
        internal static XbnfProduction Parse(ParseContext pc)
        {
            var result = new XbnfProduction();

            pc.TrySkipCCommentsAndWhiteSpace();
            // read identifier
            result.Name = ParseIdentifier(pc);
            // read attributes
            if ('<' == pc.Current)
            {
                pc.Advance();
                while (-1 != pc.Current && '>' != pc.Current)
                {
                    result.Attributes.Add(XbnfAttribute.Parse(pc));
                    pc.TrySkipCCommentsAndWhiteSpace();
                    pc.Expecting('>', ',');
                    if (',' == pc.Current)
                    {
                        pc.Advance();
                    }
                }
                pc.Expecting('>');
                pc.Advance();
            }
            pc.TrySkipCCommentsAndWhiteSpace();
            pc.Expecting(';', '=');
            if ('=' == pc.Current)
            {
                pc.Advance();
                result.Expression = XbnfExpression.Parse(pc);
            }
            pc.Expecting(';');
            pc.Advance();
            return(result);
        }
Exemplo n.º 2
0
        static RegexExpression _ParseModifier(RegexExpression expr, ParseContext pc)
        {
            var line     = pc.Line;
            var column   = pc.Column;
            var position = pc.Position;

            switch (pc.Current)
            {
            case '*':
                expr = new RegexRepeatExpression(expr);
                expr.SetLocation(line, column, position);
                pc.Advance();
                break;

            case '+':
                expr = new RegexRepeatExpression(expr, 1);
                expr.SetLocation(line, column, position);
                pc.Advance();
                break;

            case '?':
                expr = new RegexOptionalExpression(expr);
                expr.SetLocation(line, column, position);
                pc.Advance();
                break;

            case '{':
                pc.Advance();
                pc.TrySkipWhiteSpace();
                pc.Expecting('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ',', '}');
                var min = -1;
                var max = -1;
                if (',' != pc.Current && '}' != pc.Current)
                {
                    var l = pc.CaptureBuffer.Length;
                    pc.TryReadDigits();
                    min = int.Parse(pc.GetCapture(l));
                    pc.TrySkipWhiteSpace();
                }
                if (',' == pc.Current)
                {
                    pc.Advance();
                    pc.TrySkipWhiteSpace();
                    pc.Expecting('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '}');
                    if ('}' != pc.Current)
                    {
                        var l = pc.CaptureBuffer.Length;
                        pc.TryReadDigits();
                        max = int.Parse(pc.GetCapture(l));
                        pc.TrySkipWhiteSpace();
                    }
                }
                pc.Expecting('}');
                pc.Advance();
                expr = new RegexRepeatExpression(expr, min, max);
                expr.SetLocation(line, column, position);
                break;
            }
            return(expr);
        }
Exemplo n.º 3
0
        static void _ParseAttribute(EbnfDocument doc, string id, EbnfProduction prod, ParseContext pc)
        {
            pc.TrySkipCCommentsAndWhiteSpace();
            var attrid = _ParseIdentifier(pc);

            pc.TrySkipCCommentsAndWhiteSpace();
            pc.Expecting('=', '>', ',');
            object val = true;

            if ('=' == pc.Current)
            {
                pc.Advance();
                val = pc.ParseJsonValue();
            }
            pc.Expecting(',', '>');
            prod.Attributes[attrid] = val;
            pc.TrySkipCCommentsAndWhiteSpace();
        }
Exemplo n.º 4
0
 static void _ParseAttributes(EbnfDocument doc, string id, EbnfProduction prod, ParseContext pc)
 {
     pc.TrySkipCCommentsAndWhiteSpace();
     pc.Expecting('<');
     pc.Advance();
     while (-1 != pc.Current && '>' != pc.Current)
     {
         _ParseAttribute(doc, id, prod, pc);
         pc.TrySkipCCommentsAndWhiteSpace();
         pc.Expecting(',', '>');
         if (',' == pc.Current)
         {
             pc.Advance();
         }
     }
     pc.Expecting('>');
     pc.Advance();
     pc.TrySkipCCommentsAndWhiteSpace();
 }
Exemplo n.º 5
0
        static void _ParseProduction(EbnfDocument doc, ParseContext pc)
        {
            pc.TrySkipCCommentsAndWhiteSpace();
            var line     = pc.Line;
            var column   = pc.Column;
            var position = pc.Position;
            var id       = _ParseIdentifier(pc);

            pc.TrySkipCCommentsAndWhiteSpace();
            EbnfProduction prod = null;

            if (!doc.Productions.TryGetValue(id, out prod))
            {
                prod = new EbnfProduction();
                doc.Productions.Add(id, prod);
            }
            if ('<' == pc.Current)
            {
                _ParseAttributes(doc, id, prod, pc);
                pc.TrySkipCCommentsAndWhiteSpace();
            }
            pc.Expecting('=');
            pc.Advance();
            pc.Expecting();
            var expr = _ParseExpression(doc, pc);

            pc.TrySkipCCommentsAndWhiteSpace();
            pc.Expecting(';');
            pc.Advance();
            pc.TrySkipCCommentsAndWhiteSpace();
            // transform this into an OrExpression with the previous
            if (null != prod.Expression)
            {
                prod.Expression = new EbnfOrExpression(prod.Expression, expr);
            }
            else
            {
                prod.Expression = expr;
            }
            prod.SetLocationInfo(line, column, position);
        }
Exemplo n.º 6
0
        static string _ParseIdentifier(ParseContext pc)
        {
            pc.TrySkipCCommentsAndWhiteSpace();
            if (-1 == pc.Current)
            {
                pc.Expecting();
                return(null);
            }
            var l = pc.CaptureBuffer.Length;

            if ('_' != pc.Current && !char.IsLetter((char)pc.Current))
            {
                pc.Expecting("ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz".ToCharArray().Convert <int>().ToArray());
            }
            pc.CaptureCurrent();
            while (-1 != pc.Advance() && ('_' == pc.Current || '-' == pc.Current || char.IsLetterOrDigit((char)pc.Current)))
            {
                pc.CaptureCurrent();
            }
            pc.TrySkipCCommentsAndWhiteSpace();
            return(pc.GetCapture(l));
        }
Exemplo n.º 7
0
        static CfgRule _Parse(ParseContext pc)
        {
            var result = new CfgRule();

            pc.TrySkipWhiteSpace();
            pc.ClearCapture();
            pc.TryReadUntil(false, ' ', '\t', '\r', '\n', '\f', '\v', '-');
            result.Left = pc.Capture;
            pc.TrySkipWhiteSpace();
            pc.Expecting('-');
            pc.Advance();
            pc.Expecting('>');
            pc.Advance();
            while (-1 != pc.Current && '\n' != pc.Current)
            {
                pc.TrySkipWhiteSpace();
                pc.ClearCapture();
                pc.TryReadUntil(false, ' ', '\t', '\r', '\n', '\f', '\v');
                result.Right.Add(pc.Capture);
            }
            return(result);
        }
Exemplo n.º 8
0
        internal static XbnfAttribute Parse(ParseContext pc)
        {
            pc.TrySkipCCommentsAndWhiteSpace();
            var attr = new XbnfAttribute();

            attr.SetLocation(pc.Line, pc.Column, pc.Position);
            attr.Name = ParseIdentifier(pc);
            pc.TrySkipCCommentsAndWhiteSpace();
            pc.Expecting(',', '=', ',', '>');
            if ('=' == pc.Current)
            {
                pc.Advance();
                attr.Value = pc.ParseJsonValue();
            }
            else
            {
                attr.Value = true;
            }
            return(attr);
        }
Exemplo n.º 9
0
        internal static LexAttribute Parse(ParseContext pc)
        {
            SkipCommentsAndWhitespace(pc);
            var attr = new LexAttribute();

            attr.SetLocation(pc.Line, pc.Column, pc.Position);
            attr.Name = _ParseAttrName(pc);
            SkipCommentsAndWhitespace(pc);
            pc.Expecting(',', '=', ',', '>', '\n');
            if ('=' == pc.Current)
            {
                pc.Advance();
                attr.Value = pc.ParseJsonValue();
            }
            else
            {
                attr.Value = true;
            }
            return(attr);
        }
Exemplo n.º 10
0
        static EbnfExpression _ParseExpression(EbnfDocument doc, ParseContext pc)
        {
            EbnfExpression current = null;
            EbnfExpression e;
            long           position;
            int            line;
            int            column;

            pc.TrySkipCCommentsAndWhiteSpace();
            position = pc.Position; line = pc.Line; column = pc.Column;
            while (-1 != pc.Current && ']' != pc.Current && ')' != pc.Current && '}' != pc.Current && ';' != pc.Current)
            {
                pc.TrySkipCCommentsAndWhiteSpace();
                position = pc.Position; line = pc.Line; column = pc.Column;
                switch (pc.Current)
                {
                case '|':
                    pc.Advance();
                    current = new EbnfOrExpression(current, _ParseExpression(doc, pc));
                    current.SetLocationInfo(line, column, position);
                    break;

                case '(':
                    pc.Advance();
                    e = _ParseExpression(doc, pc);
                    current.SetLocationInfo(line, column, position);
                    pc.Expecting(')');
                    pc.Advance();
                    e.SetLocationInfo(line, column, position);
                    if (null == current)
                    {
                        current = e;
                    }
                    else
                    {
                        current = new EbnfConcatExpression(current, e);
                    }

                    break;

                case '[':
                    pc.Advance();
                    e = new EbnfOptionalExpression(_ParseExpression(doc, pc));
                    e.SetLocationInfo(line, column, position);
                    pc.TrySkipCCommentsAndWhiteSpace();
                    pc.Expecting(']');
                    pc.Advance();
                    if (null == current)
                    {
                        current = e;
                    }
                    else
                    {
                        current = new EbnfConcatExpression(current, e);
                    }

                    break;

                case '{':
                    pc.Advance();
                    e = new EbnfRepeatExpression(_ParseExpression(doc, pc));
                    e.SetLocationInfo(line, column, position);
                    pc.TrySkipCCommentsAndWhiteSpace();
                    pc.Expecting('}');
                    pc.Advance();
                    if ('+' == pc.Current)
                    {
                        pc.Advance();
                        ((EbnfRepeatExpression)e).IsOptional = false;
                    }
                    if (null == current)
                    {
                        current = e;
                    }
                    else
                    {
                        current = new EbnfConcatExpression(current, e);
                    }

                    break;

                case '\"':
                    e = new EbnfLiteralExpression(pc.ParseJsonString());
                    if (null == current)
                    {
                        current = e;
                    }
                    else
                    {
                        current = new EbnfConcatExpression(current, e);
                    }
                    e.SetLocationInfo(line, column, position);
                    break;

                case '\'':
                    pc.Advance();
                    pc.ClearCapture();
                    pc.TryReadUntil('\'', '\\', false);
                    pc.Expecting('\'');
                    pc.Advance();
                    e = new EbnfRegexExpression(pc.Capture);
                    if (null == current)
                    {
                        current = e;
                    }
                    else
                    {
                        current = new EbnfConcatExpression(current, e);
                    }
                    e.SetLocationInfo(line, column, position);
                    break;

                case ';':
                case ']':
                case ')':
                case '}':
                    return(current);

                default:
                    e = new EbnfRefExpression(_ParseIdentifier(pc));
                    if (null == current)
                    {
                        current = e;
                    }
                    else
                    {
                        current = new EbnfConcatExpression(current, e);
                    }
                    e.SetLocationInfo(line, column, position);
                    break;
                }
            }
            pc.TrySkipCCommentsAndWhiteSpace();
            return(current);
        }
Exemplo n.º 11
0
        static CharFA <TAccept> _Parse(ParseContext pc, TAccept accept)
        {
            CharFA <TAccept> result = new CharFA <TAccept>(true, accept);

            CharFA <TAccept> f, next;
            int ch;

            pc.EnsureStarted();
            var current = result;

            while (true)
            {
                switch (pc.Current)
                {
                case -1:
                    return(result);

                case '.':
                    pc.Advance();
                    f = current.FirstAcceptingState as CharFA <TAccept>;

                    current = Set(new CharRange[] { new CharRange(char.MinValue, char.MaxValue) }, accept);
                    switch (pc.Current)
                    {
                    case '*':
                        current = Kleene(current, accept);
                        pc.Advance();
                        break;

                    case '+':
                        current = Repeat(current, accept);
                        pc.Advance();
                        break;

                    case '?':
                        current = Optional(current, accept);
                        pc.Advance();
                        break;
                    }
                    f.IsAccepting = false;
                    f.EpsilonTransitions.Add(current);
                    break;

                case '\\':
                    if (-1 != (ch = _ParseEscape(pc)))
                    {
                        next = null;
                        switch (pc.Current)
                        {
                        case '*':
                            next = new CharFA <TAccept>();
                            next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
                            next = Kleene(next, accept);
                            pc.Advance();
                            break;

                        case '+':
                            next = new CharFA <TAccept>();
                            next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
                            next = Repeat(next, accept);
                            pc.Advance();
                            break;

                        case '?':
                            next = new CharFA <TAccept>();
                            next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
                            next = Optional(next, accept);
                            pc.Advance();
                            break;

                        default:
                            current             = current.FirstAcceptingState as CharFA <TAccept>;
                            current.IsAccepting = false;
                            current.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
                            break;
                        }
                        if (null != next)
                        {
                            current             = current.FirstAcceptingState as CharFA <TAccept>;
                            current.IsAccepting = false;
                            current.EpsilonTransitions.Add(next);
                            current = next;
                        }
                    }
                    else
                    {
                        pc.Expecting();                              // throw an error
                        return(null);                                // doesn't execute
                    }
                    break;

                case ')':
                    return(result);

                case '(':
                    pc.Advance();
                    pc.Expecting();
                    f       = current.FirstAcceptingState as CharFA <TAccept>;
                    current = _Parse(pc, accept);
                    pc.Expecting(')');
                    pc.Advance();
                    switch (pc.Current)
                    {
                    case '*':
                        current = Kleene(current, accept);
                        pc.Advance();
                        break;

                    case '+':
                        current = Repeat(current, accept);
                        pc.Advance();
                        break;

                    case '?':
                        current = Optional(current, accept);
                        pc.Advance();
                        break;
                    }
                    var ff = f.FirstAcceptingState;
                    ff.EpsilonTransitions.Add(current);
                    ff.IsAccepting = false;
                    break;

                case '|':
                    if (-1 != pc.Advance())
                    {
                        current = _Parse(pc, accept);
                        result  = Or(new CharFA <TAccept>[] { result as CharFA <TAccept>, current as CharFA <TAccept> }, accept);
                    }
                    else
                    {
                        current = current.FirstAcceptingState as CharFA <TAccept>;
                        result  = Optional(result, accept);
                    }
                    break;

                case '[':
                    pc.ClearCapture();
                    pc.Advance();
                    pc.Expecting();
                    bool not = false;
                    if ('^' == pc.Current)
                    {
                        not = true;
                        pc.Advance();
                        pc.Expecting();
                    }
                    pc.TryReadUntil(']', '\\', false);
                    pc.Expecting(']');
                    pc.Advance();

                    var r = (!not && "." == pc.Capture) ?
                            new CharRange[] { new CharRange(char.MinValue, char.MaxValue) } :
                    _ParseRanges(pc.Capture, true);
                    if (not)
                    {
                        r = CharRange.NotRanges(r);
                    }
                    f       = current.FirstAcceptingState as CharFA <TAccept>;
                    current = Set(r, accept);
                    switch (pc.Current)
                    {
                    case '*':
                        current = Kleene(current, accept);
                        pc.Advance();
                        break;

                    case '+':
                        current = Repeat(current, accept);
                        pc.Advance();
                        break;

                    case '?':
                        current = Optional(current, accept);
                        pc.Advance();
                        break;
                    }
                    f.IsAccepting = false;
                    f.EpsilonTransitions.Add(current);
                    break;

                default:
                    ch = pc.Current;
                    pc.Advance();
                    next = null;
                    switch (pc.Current)
                    {
                    case '*':
                        next = new CharFA <TAccept>();
                        next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
                        next = Kleene(next, accept);
                        pc.Advance();
                        break;

                    case '+':
                        next = new CharFA <TAccept>();
                        next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
                        next = Repeat(next, accept);
                        pc.Advance();
                        break;

                    case '?':
                        next = new CharFA <TAccept>();

                        next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
                        next = Optional(next, accept);
                        pc.Advance();
                        break;

                    default:
                        current             = current.FirstAcceptingState as CharFA <TAccept>;
                        current.IsAccepting = false;
                        current.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
                        break;
                    }
                    if (null != next)
                    {
                        current             = current.FirstAcceptingState as CharFA <TAccept>;
                        current.IsAccepting = false;
                        current.EpsilonTransitions.Add(next);
                        current = next;
                    }
                    break;
                }
            }
        }
Exemplo n.º 12
0
        internal static RegexExpression Parse(ParseContext pc)
        {
            RegexExpression result = null, next = null;
            int             ich;

            pc.EnsureStarted();
            var line = pc.Line;
            var column   = pc.Column;
            var position = pc.Position;

            while (true)
            {
                switch (pc.Current)
                {
                case -1:
                    return(result);

                case '.':
                    var nset = new RegexCharsetExpression(new RegexCharsetEntry[] { new RegexCharsetRangeEntry(char.MinValue, char.MaxValue) }, false);
                    nset.SetLocation(line, column, position);
                    if (null == result)
                    {
                        result = nset;
                    }
                    else
                    {
                        result = new RegexConcatExpression(result, nset);
                        result.SetLocation(line, column, position);
                    }
                    pc.Advance();
                    result   = _ParseModifier(result, pc);
                    line     = pc.Line;
                    column   = pc.Column;
                    position = pc.Position;
                    break;

                case '\\':
                    if (-1 != (ich = _ParseEscape(pc)))
                    {
                        next = new RegexLiteralExpression((char)ich);
                        next.SetLocation(line, column, position);
                        next = _ParseModifier(next, pc);
                        if (null != result)
                        {
                            result = new RegexConcatExpression(result, next);
                            result.SetLocation(line, column, position);
                        }
                        else
                        {
                            result = next;
                        }
                    }
                    else
                    {
                        pc.Expecting();                              // throw an error
                        return(null);                                // doesn't execute
                    }
                    line     = pc.Line;
                    column   = pc.Column;
                    position = pc.Position;
                    break;

                case ')':
                    return(result);

                case '(':
                    pc.Advance();
                    pc.Expecting();
                    next = Parse(pc);
                    pc.Expecting(')');
                    pc.Advance();
                    next = _ParseModifier(next, pc);
                    if (null == result)
                    {
                        result = next;
                    }
                    else
                    {
                        result = new RegexConcatExpression(result, next);
                        result.SetLocation(line, column, position);
                    }
                    line     = pc.Line;
                    column   = pc.Column;
                    position = pc.Position;
                    break;

                case '|':
                    if (-1 != pc.Advance())
                    {
                        next   = Parse(pc);
                        result = new RegexOrExpression(result, next);
                        result.SetLocation(line, column, position);
                    }
                    else
                    {
                        result = new RegexOrExpression(result, null);
                        result.SetLocation(line, column, position);
                    }
                    line     = pc.Line;
                    column   = pc.Column;
                    position = pc.Position;
                    break;

                case '[':
                    pc.ClearCapture();
                    pc.Advance();
                    pc.Expecting();
                    bool not = false;


                    if ('^' == pc.Current)
                    {
                        not = true;
                        pc.Advance();
                        pc.Expecting();
                    }
                    var ranges = _ParseRanges(pc);
                    if (ranges.Count == 0)
                    {
                        System.Diagnostics.Debugger.Break();
                    }
                    pc.Expecting(']');
                    pc.Advance();
                    next = new RegexCharsetExpression(ranges, not);
                    next.SetLocation(line, column, position);
                    next = _ParseModifier(next, pc);

                    if (null == result)
                    {
                        result = next;
                    }
                    else
                    {
                        result = new RegexConcatExpression(result, next);
                        result.SetLocation(pc.Line, pc.Column, pc.Position);
                    }
                    line     = pc.Line;
                    column   = pc.Column;
                    position = pc.Position;
                    break;

                default:
                    ich  = pc.Current;
                    next = new RegexLiteralExpression((char)ich);
                    next.SetLocation(line, column, position);
                    pc.Advance();
                    next = _ParseModifier(next, pc);
                    if (null == result)
                    {
                        result = next;
                    }
                    else
                    {
                        result = new RegexConcatExpression(result, next);
                        result.SetLocation(line, column, position);
                    }
                    line     = pc.Line;
                    column   = pc.Column;
                    position = pc.Position;
                    break;
                }
            }
        }
Exemplo n.º 13
0
        static IList <RegexCharsetEntry> _ParseRanges(ParseContext pc)
        {
            pc.EnsureStarted();
            var result             = new List <RegexCharsetEntry>();
            RegexCharsetEntry next = null;
            bool readDash          = false;

            while (-1 != pc.Current && ']' != pc.Current)
            {
                switch (pc.Current)
                {
                case '[':                         // char class
                    if (null != next)
                    {
                        result.Add(next);
                        if (readDash)
                        {
                            result.Add(new RegexCharsetCharEntry('-'));
                        }
                        result.Add(new RegexCharsetCharEntry('-'));
                    }
                    pc.Advance();
                    pc.Expecting(':');
                    pc.Advance();
                    var l = pc.CaptureBuffer.Length;
                    pc.TryReadUntil(':', false);
                    var n = pc.GetCapture(l);
                    pc.Advance();
                    pc.Expecting(']');
                    pc.Advance();
                    result.Add(new RegexCharsetClassEntry(n));
                    readDash = false;
                    next     = null;
                    break;

                case '\\':
                    //pc.Advance();
                    //pc.Expecting();
                    var ch = (char)_ParseEscape(pc);
                    if (null == next)
                    {
                        next = new RegexCharsetCharEntry(ch);
                    }
                    else
                    {
                        if (readDash)
                        {
                            result.Add(new RegexCharsetRangeEntry(((RegexCharsetCharEntry)next).Value, ch));
                            next     = null;
                            readDash = false;
                        }
                        else
                        {
                            result.Add(next);
                            next = new RegexCharsetCharEntry(ch);
                        }
                    }
                    break;

                case '-':
                    pc.Advance();
                    if (null == next)
                    {
                        next     = new RegexCharsetCharEntry('-');
                        readDash = false;
                    }
                    else
                    {
                        if (readDash)
                        {
                            result.Add(next);
                        }
                        readDash = true;
                    }
                    break;

                default:
                    if (null == next)
                    {
                        next = new RegexCharsetCharEntry((char)pc.Current);
                    }
                    else
                    {
                        if (readDash)
                        {
                            result.Add(new RegexCharsetRangeEntry(((RegexCharsetCharEntry)next).Value, (char)pc.Current));
                            next     = null;
                            readDash = false;
                        }
                        else
                        {
                            result.Add(next);
                            next = new RegexCharsetCharEntry((char)pc.Current);
                        }
                    }
                    pc.Advance();
                    break;
                }
            }
            if (null != next)
            {
                result.Add(next);
                if (readDash)
                {
                    next = new RegexCharsetCharEntry('-');
                    result.Add(next);
                }
            }
            return(result);
        }
Exemplo n.º 14
0
        internal static LexDocument Parse(ParseContext pc)
        {
            var result = new LexDocument();

            while (-1 != pc.Current)
            {
                var line     = pc.Line;
                var column   = pc.Column;
                var position = pc.Position;
                LexNode.SkipCommentsAndWhitespace(pc);
                while ('\n' == pc.Current)
                {
                    pc.Advance();
                    LexNode.SkipCommentsAndWhitespace(pc);
                }
                var id = LexNode.ParseIdentifier(pc);
                if (string.IsNullOrEmpty(id))
                {
                    pc.Advance();
                    LexNode.SkipCommentsAndWhitespace(pc);
                    continue;
                }
                LexNode.SkipCommentsAndWhitespace(pc);

                pc.Expecting(':', '-', '=');
                if (':' == pc.Current)                 // attribute set
                {
                    pc.Advance();
                    var d = new LexAttributeList();
                    while (-1 != pc.Current && '\n' != pc.Current)
                    {
                        var attr = LexAttribute.Parse(pc);
                        d.Add(attr);

                        LexNode.SkipCommentsAndWhitespace(pc);
                        pc.Expecting('\n', ',', -1);
                        if (',' == pc.Current)
                        {
                            pc.Advance();
                        }
                    }
                    result.AttributeSets.Add(id, d);
                    LexNode.SkipCommentsAndWhitespace(pc);
                }
                else if ('=' == pc.Current)
                {
                    pc.Advance();
                    LexNode.SkipCommentsAndWhitespace(pc);
                    pc.Expecting('\'');
                    pc.Advance();
                    var l = pc.CaptureBuffer.Length;
                    pc.TryReadUntil('\'', '\\', false);
                    pc.Expecting('\'');
                    pc.Advance();
                    var rx = pc.GetCapture(l);
                    // make sure to capture the line numbers properly:
                    var rpc = ParseContext.Create(rx);
                    rpc.EnsureStarted();
                    rpc.SetLocation(pc.Line, pc.Column, pc.Position);
                    var rule = new LexRule(id, RegexExpression.Parse(rpc));
                    rule.SetLocation(line, column, position);
                    result.Rules.Add(rule);
                }
                else if ('-' == pc.Current)
                {
                    pc.TrySkipUntil('\n', true);
                }
                LexNode.SkipCommentsAndWhitespace(pc);
                if ('\n' == pc.Current)
                {
                    pc.Advance();
                }
            }
            return(result);
        }