Parser CharacterSet(Match match) { var alt = new AlternativeParser(); var inverse = match.Text.StartsWith("[^", StringComparison.Ordinal); var characters = new List<char>(); foreach (var child in match.Matches.Where(r => r.Name != null)) { switch (child.Name) { case "character range": var first = Character(child.Matches.First(r => r.Name == "character")); var last = Character(child.Matches.Last(r => r.Name == "character")); if (first != null && last != null) alt.Add(new CharRangeTerminal(first.Value, last.Value) { Inverse = inverse }); break; case "character": var character = Character(child); if (character != null) characters.Add(character.Value); break; default: throw new FormatException(string.Format("Invalid character set child for text '{0}'", child.Text)); } } if (characters.Count > 0) { alt.Add(new CharSetTerminal(characters.ToArray()) { Inverse = inverse }); } if (alt.Items.Count > 1) return alt; if (alt.Items.Count > 0) return alt.Items[0]; return new UnaryParser(); //throw new FormatException(string.Format("Character set has no characters '{0}'", match.Text)); }
public EbnfGrammar(EbnfStyle style) : base("ebnf") { Style = style; DefineCommonNonTerminals = true; GenerateSpecialSequences(); // terminals var comment = style.HasFlag(EbnfStyle.BracketComments) ? new GroupParser("(*", "*)") : new GroupParser("/*", "*/"); var ows = -(Terminals.WhiteSpace | comment); var rws = +(Terminals.WhiteSpace | comment); var hex_character = ("#x" & +Terminals.HexDigit); var character = (("\\" & Terminals.AnyChar) | hex_character | Terminals.AnyChar.Except("]")).WithName("character"); var character_range = (character & "-" & character).WithName("character range"); var character_set = ("[" & ~(Parser)"^" & +(character_range | character) & "]").WithName("character set"); var terminal_string = new StringParser { QuoteCharacters = new [] { '\"', '\'', '’' }, Name = "terminal string" }; var special_sequence = ("?" & (+Terminals.AnyChar).Until("?").WithName("name") & "?").WithName("special sequence"); var meta_identifier_terminal = Terminals.Letter & -(Terminals.LetterOrDigit | '_'); var integer = new NumberParser().WithName("integer"); // nonterminals var definition_list = new RepeatParser(0).WithName("definition list"); var single_definition = new RepeatParser(1).WithName("single definition"); var term = new SequenceParser().WithName("term"); var primary = new AlternativeParser().WithName("primary"); var exception = new UnaryParser("exception"); var factor = new SequenceParser().WithName("factor"); var meta_identifier = new RepeatParser(1).WithName("meta identifier"); var syntax_rule = new SequenceParser().WithName("syntax rule"); var rule_equals = new AlternativeParser().WithName("equals"); Parser meta_reference = meta_identifier; Parser grouped_sequence = ("(" & ows & definition_list & ows & ")").WithName("grouped sequence"); if (style.HasFlag(EbnfStyle.SquareBracketAsOptional)) { primary.Add(("[" & ows & definition_list & ows & "]").WithName("optional sequence")); } if (!style.HasFlag(EbnfStyle.CardinalityFlags)) { var repeated_sequence = ("{" & ows & definition_list & ows & "}").WithName("repeated sequence"); primary.Add(repeated_sequence); } // rules meta_identifier.Inner = meta_identifier_terminal; meta_identifier.Separator = +(Terminals.SingleLineWhiteSpace); if (!style.HasFlag(EbnfStyle.CommaSeparator)) { // w3c identifiers must be a single word meta_identifier.Maximum = 1; meta_reference = meta_reference.NotFollowedBy(ows & rule_equals); } primary.Add(grouped_sequence, meta_reference, terminal_string, special_sequence); if (style.HasFlag(EbnfStyle.CharacterSets) && !style.HasFlag(EbnfStyle.SquareBracketAsOptional)) { // w3c supports character sets primary.Add(hex_character.Named("hex character")); primary.Add(character_set); } if (style.HasFlag(EbnfStyle.NumericCardinality)) factor.Add(~(integer & ows & "*" & ows)); factor.Add(primary); if (style.HasFlag(EbnfStyle.CardinalityFlags)) { // w3c defines cardinality at the end of a factor var flags = style.HasFlag(EbnfStyle.SquareBracketAsOptional) ? "*+" : "?*+"; factor.Add(~(ows & Terminals.Set(flags).WithName("cardinality"))); } term.Add(factor, ~(ows & "-" & ows & exception)); exception.Inner = term; single_definition.Inner = term; single_definition.Separator = style.HasFlag(EbnfStyle.CommaSeparator) ? (Parser)(ows & "," & ows) : ows; definition_list.Inner = single_definition; definition_list.Separator = ows & "|" & ows; rule_equals.Add(style.HasFlag(EbnfStyle.DoubleColonEquals) ? "::=" : "=", ":="); syntax_rule.Add(meta_identifier, ows, rule_equals, ows, definition_list); if (style.HasFlag(EbnfStyle.SemicolonTerminator)) syntax_rule.Add(ows, ";"); // iso rules are terminated by a semicolon var syntax_rules = +syntax_rule; syntax_rules.Separator = style.HasFlag(EbnfStyle.SemicolonTerminator) ? ows : rws; Inner = ows & syntax_rules & ows; AttachEvents(); }