public bool HasSingleRule(SymbolInfo symbol)
{
IEnumerable <Production> rules = ParserProductions.Where(it => it.LhsSymbol.SymbolName == symbol.SymbolName);
if (rules.Count() != 1)
{
return(false);
}
return(rules.Single().RhsAlternatives.Count() == 1);
}
internal Grammar(IEnumerable <Tuple <GrammarElementEnum, object> > elements,
IEnumerable <LexItem> implicitLexerRules,
List <string> warnings)
{
var throw_errors = new List <string>();
{
Dictionary <GrammarElementEnum, int> elem_counts = EnumExtensions.GetValues <GrammarElementEnum>().ToDictionary(it => it, it => 0);
foreach (Tuple <GrammarElementEnum, object> elem in elements)
{
if (elem.Item2 != null)
{
++elem_counts[elem.Item1];
}
}
var optionals = new HashSet <GrammarElementEnum>(new GrammarElementEnum[] {
GrammarElementEnum.Types,
GrammarElementEnum.Terminals,
GrammarElementEnum.Options,
GrammarElementEnum.Prededence,
GrammarElementEnum.LexerTypeInfo,
GrammarElementEnum.ExplicitLexerRules,
GrammarElementEnum.LexerStates,
GrammarElementEnum.ParserTypeInfo,
GrammarElementEnum.ParserRules,
GrammarElementEnum.PatternsInfo,
GrammarElementEnum.Using
});
foreach (KeyValuePair <GrammarElementEnum, int> count in elem_counts.Where(it => it.Value != 1))
{
if (count.Value > 1)
{
throw ParseControlException.NewAndRun(count.Key.ToString() + " section is duplicated");
}
// if not optional section
else if (!optionals.Contains(count.Key))
{
throw ParseControlException.NewAndRun(count.Key.ToString() + " section is missing");
}
}
{
// if we have lexer name section, then we have to have lexer rules as well
// in reverse -- if we don't have the first, we cannot have the latter one and lexer states section
// so it is not symmetric!
var lexer_count = elem_counts[GrammarElementEnum.LexerTypeInfo];
if (elem_counts[GrammarElementEnum.LexerStates] > lexer_count ||
elem_counts[GrammarElementEnum.ExplicitLexerRules] != lexer_count)
{
throw ParseControlException.NewAndRun("Lexer definition is given only partially: lexer name section "
+ (lexer_count > 0 ? "exists" : "does not exist") + " while lexer states section "
+ (elem_counts[GrammarElementEnum.LexerStates] > 0 ? "exists" : "does not exist") + " and lexer rules section "
+ (elem_counts[GrammarElementEnum.ExplicitLexerRules] > 0 ? "exists" : "does not exist") + ".");
}
}
if (elem_counts[GrammarElementEnum.ParserRules] != elem_counts[GrammarElementEnum.ParserTypeInfo])
{
throw ParseControlException.NewAndRun("Parser definition is given only partially");
}
}
Dictionary <GrammarElementEnum, object> dict_elements = EnumExtensions.GetValues <GrammarElementEnum>()
.ToDictionary(it => it, it => (object)null);
foreach (Tuple <GrammarElementEnum, object> elem in elements)
{
dict_elements[elem.Item1] = elem.Item2;
}
this.usingList = (((IEnumerable <string>)dict_elements[GrammarElementEnum.Using]) ?? new string[] { }).ToList();
this.types = (((IEnumerable <SymbolInfo>)dict_elements[GrammarElementEnum.Types]) ?? new SymbolInfo[] { }).ToDictionary(it => it.SymbolName, it => it.TypeName);
this.guessed_types = new Dictionary <string, string>();
this.NamespaceName = ((string)dict_elements[GrammarElementEnum.Namespace]);
this.TokenTypeInfo = ((TokenInfo)dict_elements[GrammarElementEnum.TokenName]);
this.PatternsTypeInfo = ((PatternsInfo)dict_elements[GrammarElementEnum.PatternsInfo]) ?? new PatternsInfo(null, null);
this.LexerTypeInfo = ((FactoryTypeInfo)dict_elements[GrammarElementEnum.LexerTypeInfo]);
this.Options = ((GrammarOptions)dict_elements[GrammarElementEnum.Options]) ?? new GrammarOptions();
this.LexerStates = ((StatesInfo)dict_elements[GrammarElementEnum.LexerStates]) ?? StatesInfo.CreateDefault();
// implicit rules first, because lexer matches text in longest-first fashion
// when user explicitly adds something like <anything> rule with reversed concat order
// implicit rules will never be matched
this.lexerRules = implicitLexerRules.Concat((((IEnumerable <IScanningRule>)dict_elements[GrammarElementEnum.ExplicitLexerRules]) ?? new LexItem[] { })
.Select(it => it as LexItem).Where(it => it != null)).ToList();
{
IEnumerable <LexPatternVariable> pattern_vars = (((IEnumerable <IScanningRule>)dict_elements[GrammarElementEnum.ExplicitLexerRules]) ?? new LexPatternVariable[] { })
.Select(it => it as LexPatternVariable).Where(it => it != null).ToArray();
this.LexerPatternFields = pattern_vars.Where(it => it.WithField).ToArray();
this.lexerPatternNames = pattern_vars.ToDictionary(it => it.Name, it => it.Pattern);
}
this.lexerRules.ForEach(it => it.OutputPattern = mergeLexPatterns(it.InputPatterns));
this.ParserTypeInfo = ((FactoryTypeInfo)dict_elements[GrammarElementEnum.ParserTypeInfo]);
this.parserPrecedences = (((IEnumerable <Precedence>)dict_elements[GrammarElementEnum.Prededence]) ?? Enumerable.Empty <Precedence>()).ToList();
this.terminalRegistry = new OrderedSet <string>(
(new[] { EOFSymbol })
.Concat((((IEnumerable <string>)dict_elements[GrammarElementEnum.Terminals]) ?? new string[] { }))
.Concat(
lexerRules.Select(lex_it => lex_it.Context.Concat(lex_it.TerminalName)).Flatten()
// error symbol can appear in lexer productions, it is not a terminal though
.Where(s => s != null && s != Grammar.ErrorSymbol)));
this.parserProductions = new List <Production>();
AddProductions(((IEnumerable <Production>)dict_elements[GrammarElementEnum.ParserRules]) ?? new Production[] { });
this.symbolRegistry = new OrderedSet <string>(
(new[] { ErrorSymbol })
.Concat(terminalRegistry) // EOF starts that set
.Concat(nonTerminalRegistry)
.Concat(ParserProductions
.Select(prod => prod.RhsAlternatives
.Select(alt => alt.RhsGroups
.Select(grp => grp.GetSymbols().Select(s => s.SymbolName))
.Flatten())
.Flatten())
.Flatten()));
// here we get partial mapping (useful for lexer, which sees only part of all symbols)
InitSymbolMapping();
if (!IsParserBuilt)
{
var errors = new List <string>();
if (dict_elements[GrammarElementEnum.Types] != null)
{
errors.Add("types");
}
if (dict_elements[GrammarElementEnum.Prededence] != null)
{
errors.Add("precedence");
}
if (dict_elements[GrammarElementEnum.ParserRules] != null)
{
errors.Add("parser productions");
}
if (errors.Any())
{
throw ParseControlException.NewAndRun("Parser is not built (no parser name is given); " + errors.Join(", ") + " section(s) are meaningless.");
}
}
{
IEnumerable <string> undef_symbols = new HashSet <string>(types.Select(it => it.Key).Where(it => !symbolRegistry.Contains(it)));
if (undef_symbols.Any())
{
warnings.Add("Undefined symbol(s) in types section: " + String.Join(", ", undef_symbols));
}
}
if (IsParserBuilt)
{
var rhs_symbol_names = new HashSet <string>(ParserProductions.Select(it => it.RhsAlternatives).Flatten()
.Select(it => it.RhsGroups).Flatten()
.Select(it => it.GetSymbols()).Flatten()
.Select(it => it.SymbolName));
IEnumerable <string> unused_terminals = terminalRegistry.Where(it => it != Grammar.EOFSymbol && !rhs_symbol_names.Contains(it)).ToList();
if (unused_terminals.Any())
{
warnings.Add("Unused terminal(s) in parsing section: " + String.Join(", ", unused_terminals));
}
}
ParseControlException.ThrowAndRun(throw_errors);
}
internal void AddProductions(IEnumerable <Production> productions)
{
foreach (SymbolInfo sym_info in productions.Select(it => it.LhsSymbol).Where(it => it.TypeName != null))
{
{
string typename;
if (!this.types.TryGetValue(sym_info.SymbolName, out typename))
{
setTypeNameOfSymbol(sym_info.SymbolName, sym_info.TypeName);
}
else if (typename != sym_info.TypeName)
{
throw ParseControlException.NewAndRun(sym_info.SymbolName + " defined as " + sym_info.TypeName + " has already type " + typename);
}
}
}
foreach (Production prod in productions)
{
foreach (AltRule alt in prod.RhsAlternatives.Where(it => it.Code != null))
{
string guess = alt.Code.BuildBody(presentVariables: null).GuessTypeName();
string typename;
if (!this.guessed_types.TryGetValue(prod.LhsSymbol.SymbolName, out typename))
{
// it can be null, meaning it was not recognized
this.guessed_types.Add(prod.LhsSymbol.SymbolName, guess);
}
// if there is a conflict with guessing set it is as not recognized
else if (typename != guess)
{
this.guessed_types[prod.LhsSymbol.SymbolName] = null;
}
}
}
parserProductions.AddRange(productions);
this.nonTerminalRegistry = new HashSet <string>(ParserProductions.Select(prod => prod.LhsSymbol.SymbolName));
var unknown = new HashSet <string>();
var lhs_terminals = new List <string>();
foreach (Production prod in productions)
{
foreach (AltRule alt in prod.RhsAlternatives)
{
foreach (IEnumerable <RhsSymbol> symbols in alt.RhsGroups.Select(it => it.GetSymbols()))
{
unknown.AddRange(symbols
.Where(sym => !terminalRegistry.Contains(sym.SymbolName) &&
!nonTerminalRegistry.Contains(sym.SymbolName) &&
!types.ContainsKey(sym.SymbolName) &&
sym.SymbolName != ErrorSymbol)
.Select(it => it.Coords.XYString() + " " + it.SymbolName));
}
}
if (terminalRegistry.Contains(prod.LhsSymbol.SymbolName))
{
lhs_terminals.Add(prod.LhsSymbol.SymbolName);
}
}
var errors = new List <string>();
if (lhs_terminals.Any())
{
errors.Add("Terminal(s) " + lhs_terminals.Join(",") + " cannot be used at LHS of the production");
}
if (unknown.Any())
{
errors.Add("Undefined symbol(s): " + String.Join(",", unknown));
}
ParseControlException.ThrowAndRun(errors);
}