/// <summary>
/// Reads runtime data for lexer/parser construction from a binary file.
/// </summary>
/// <param name="inFile">The name of the file from which the data shall be read.</param>
/// <param name="lexerData">The LexerData serialized from the Stream.</param>
/// <param name="parserData">The ParserData serialized from the Stream.</param>
public static void ReadRuntimeDataFromFile(string inFile, out LexerData lexerData, out ParserData parserData)
{
Stream inStream = new FileStream(inFile, FileMode.Open, FileAccess.Read, FileShare.Read);
lexerData = LexerData.FromStream(inStream);
parserData = ParserData.FromStream(inStream);
inStream.Close();
}
/// <summary>
/// Creates a new Grammar instance and sets it's GrammarDefiniton, LexerData and
/// GrammarCode properties to provided values. The ParserData structure will be
/// initialized and it's ProductionOutlines and SymbolNames properties will be set.
/// </summary>
/// <param name="grammarDefinition">The definition of the grammar.</param>
/// <param name="lexerData">A structure defining the lexer's runtime behaviour.</param>
/// <param name="grammarCode">The collection of user code describing the actions of the parser.</param>
public Grammar(GrammarDefinition grammarDefinition, LexerData lexerData, GrammarCode grammarCode)
{
this.grammarDefinition = grammarDefinition;
this.lexerData = lexerData;
this.grammarCode = grammarCode;
ProductionOutline[] productionOutlines = new ProductionOutline[grammarDefinition.Productions.Length];
for (int i = 0; i < productionOutlines.Length; i++)
{
productionOutlines[i] = new ProductionOutline(grammarDefinition.Productions[i].LHSSymbol, grammarDefinition.Productions[i].RHSSymbols.Count);
}
this.parserData = new ParserData(grammarDefinition.SymbolNames, productionOutlines);
}
/// <summary>
/// Constructs a Lexer using the necessary data stored in the LexerData instance.
/// </summary>
/// <param name="lexerData">The LexerData containing information necessary to construct the Lexer.</param>
public Lexer(LexerData lexerData)
{
this.groupSymbolCodes = lexerData.GroupSymbolCodes;
this.regex = lexerData.Regex;
}
public static Grammar ParseGrammar(string specificationPath, out IList <string> warningMessages)
{
#if BOOTSTRAP
GrammarLexer lexer = new GrammarLexer();
lexer.SourceString = File.ReadAllText(specificationPath);
Token token = lexer.GetNextToken();
//sem si budeme ukládat chyby a warningy; pokud se vyskytne nějaká chyba, čteme dál a
//až na konci vyhodíme výjimku se všemi chybami a warningami; pokud vše proběhne bez
//závažnějších chyb, tak seznam warningů pošlem zpátky volajícímu
List <string> errorMessages = new List <string>();
warningMessages = new List <string>();
//the code to be inserted at the start of the generated code
string headerCode = null;
//seznam jmen všech symbolů; slouží potom jako převodní tabulka z kódu symbolu na jeho jméno
List <string> symbolNames = new List <string>();
//"inverzní tabulka" k symbolNames, která nám pro jméno symbolu řekne jeho kód
Dictionary <string, int> symbolCodes = new Dictionary <string, int>();
//seznam regulárních výrazů definujících terminální symboly; netvoříme z nich rovnou výsledný
//lexerův regex, ale ukládáme si je zvlášť, abychom v případě chyby při kompilaci celkového regexu
//mohli jednodušše otestovat, které výrazy jsou na vině
List <string> regexes = new List <string>();
//pro každý výraz v regexes si pamatujeme pozici, kde jsme ho našli, abychom mohli vydat podrobnější
//zprávu
List <int> regexLines = new List <int>();
List <int> regexColumns = new List <int>();
//pro každý výraz v regexes si také pamatujeme kód symbolu, který je popisován oním výrazem,
//v případě, že výraz má matchovat řetězce, které chceme ignorovat, je v tomto poli hodnota -1;
//jedná se o runtime data, která pak přímo používá náš lexer
List <int> groupSymbolCodes = new List <int>();
//výsledný regulární výraz, pomocí kterého lexer scanuje tokeny; druhá část runtime dat pro náš lexer
Regex regex = null;
//jméno pseudoterminálu, jehož tokeny se nemají posílat parseru, ale zahazovat
string nullTerminal = "";
//globální optiony .NETímu regex stroji (case insensitive, multiline...)
string regexOpts = null;
if (token.SymbolCode == CODE_HEADER)
{
token = lexer.GetNextToken();
headerCode = token.Value;
token = lexer.GetNextToken();
}
// skipping LEXER
token = lexer.GetNextToken();
if (token.SymbolCode == CODE_NULL)
{
token = lexer.GetNextToken();
nullTerminal = token.Value;
token = lexer.GetNextToken();
}
if (token.SymbolCode == CODE_REGEXOPTS)
{
regexOpts = token.Value;
token = lexer.GetNextToken();
}
symbolNames.Add("$end");
symbolCodes["$end"] = 0;
while (token.SymbolCode == CODE_IDENTIFIER)
{
string symbol = token.Value;
token = lexer.GetNextToken();
// skipping EQUALS
token = lexer.GetNextToken();
string capturingRegex = token.Value;
token = lexer.GetNextToken();
if (symbol == nullTerminal)
{
groupSymbolCodes.Add(-1);
}
else
{
if (!symbolCodes.ContainsKey(symbol))
{
symbolNames.Add(symbol);
symbolCodes[symbol] = symbolNames.Count - 1;
}
groupSymbolCodes.Add(symbolCodes[symbol]);
}
regexes.Add(capturingRegex);
regexLines.Add(token.LineNumber);
regexColumns.Add(token.ColumnNumber);
}
StringBuilder pattern = new StringBuilder();
if (regexOpts != null)
{
pattern.Append(regexOpts);
}
for (int i = 0; i < regexes.Count; i++)
{
//všechny uživatelovi regulární výrazy oddělíme ořítky a zapíšeme je v pořadí, v jakém nám
//je zadal (v .NETím Regex enginu mají výrazy v ořítku víc nalevo přednost) a každý výraz
//strčíme do capture groupy pojmenované __i, kde i je pořadové číslo výrazu, počítáno od 0
if (i != 0)
{
pattern.Append('|');
}
pattern.AppendFormat("(?<{0}>{1})", "__" + i.ToString(), regexes[i]);
}
try
{
regex = new Regex(pattern.ToString(), RegexOptions.Compiled);
}
catch (ArgumentException)
{
try
{
new Regex(regexOpts);
}
catch (ArgumentException)
{
// FIXME: We no longer have the line and column data on regexOpts.
errorMessages.Add(string.Format("{0},{1}: The RegEx options are invalid.", -1, -1));
}
for (int i = 0; i < regexes.Count; i++)
{
try
{
new Regex(regexes[i]);
}
catch (ArgumentException)
{
errorMessages.Add(string.Format("{0},{1}: This regular expression is invalid.",
regexLines[i], regexColumns[i]));
}
}
}
int numTerminals = symbolNames.Count;
// skipping PARSER
token = lexer.GetNextToken();
//neterminály, které se objevily na levé straně nějakého pravidla
HashSet <int> reducibleNonterminals = new HashSet <int>();
//neterminály, které se objevily na pravé straně nějakého pravidla
HashSet <int> usedNonterminals = new HashSet <int>();
bool[] terminalUsed = new bool[numTerminals];
List <ProductionWithAction> productions = new List <ProductionWithAction>();
symbolNames.Add("$start");
symbolCodes["$start"] = numTerminals;
//semhle dáme <$start> výjimečně, protože ani nechceme,
//aby ho někdo dával na pravou stranu nějakého pravidla
usedNonterminals.Add(symbolCodes["$start"]);
// skipping START
token = lexer.GetNextToken();
// skipping LANGLE
token = lexer.GetNextToken();
string startSymbol = token.Value;
if (symbolCodes.ContainsKey(startSymbol) && symbolCodes[startSymbol] < numTerminals)
{
errorMessages.Add(string.Format("{0},{1}: The nonterminal <{2}> shares it's name with a terminal symbol.",
token.LineNumber, token.ColumnNumber, startSymbol));
}
token = lexer.GetNextToken();
// skipping RANGLE
token = lexer.GetNextToken();
symbolNames.Add(startSymbol);
symbolCodes[startSymbol] = symbolNames.Count - 1;
string userObjectType = null;
if (token.SymbolCode == CODE_USEROBJECT)
{
token = lexer.GetNextToken();
if (token.SymbolCode == CODE_QUOTED)
{
userObjectType = token.Value.Substring(1, token.Value.Length - 2);
token = lexer.GetNextToken();
}
else
{
StringBuilder typeBuilder = new StringBuilder(token.Value);
token = lexer.GetNextToken();
while (token.SymbolCode == CODE_DOT)
{
typeBuilder.Append(".");
token = lexer.GetNextToken();
typeBuilder.Append(token.Value);
token = lexer.GetNextToken();
}
userObjectType = typeBuilder.ToString();
}
}
//naše 0. pravidlo, které výstižně popisuje způsob, jakým si gramatiku upravujeme
productions.Add(new ProductionWithAction(new Production(
symbolCodes["$start"], new int[] { symbolCodes[startSymbol], symbolCodes["$end"] }), "{ return _1; }"));
reducibleNonterminals.Add(symbolCodes["$start"]);
usedNonterminals.Add(symbolCodes[startSymbol]);
terminalUsed[symbolCodes["$end"]] = true;
var typeMappings = new Dictionary <string, string>();
//zpracování pravidel
while (token.SymbolCode != CODE_END)
{
if (token.SymbolCode == CODE_TYPE)
{
token = lexer.GetNextToken();
// skipping LANGLE
token = lexer.GetNextToken();
string nonterminal = token.Value;
if (symbolCodes.ContainsKey(nonterminal) && symbolCodes[nonterminal] < numTerminals)
{
errorMessages.Add(string.Format("{0},{1}: The nonterminal <{2}> shares it's name with a terminal symbol.",
token.LineNumber, token.ColumnNumber, nonterminal));
}
if (!symbolCodes.ContainsKey(nonterminal))
{
symbolNames.Add(nonterminal);
symbolCodes[nonterminal] = symbolNames.Count - 1;
}
token = lexer.GetNextToken();
// skipping RANGLE
token = lexer.GetNextToken();
if (token.SymbolCode == CODE_QUOTED)
{
// QUOTED
typeMappings.Add(nonterminal, token.Value.Substring(1, token.Value.Length - 2));
token = lexer.GetNextToken();
}
else
{
StringBuilder typeBuilder = new StringBuilder(token.Value);
token = lexer.GetNextToken();
while (token.SymbolCode == CODE_DOT)
{
typeBuilder.Append(".");
token = lexer.GetNextToken();
typeBuilder.Append(token.Value);
token = lexer.GetNextToken();
}
typeMappings.Add(nonterminal, typeBuilder.ToString());
}
}
else
{
//extrahujeme symbol na levé straně a zpracujeme ho
// skipping LANGLE
token = lexer.GetNextToken();
string lhsSymbol = token.Value;
if (symbolCodes.ContainsKey(lhsSymbol) && symbolCodes[lhsSymbol] < numTerminals)
{
errorMessages.Add(string.Format("{0},{1}: The nonterminal <{2}> shares it's name with a terminal symbol.",
token.LineNumber, token.ColumnNumber, lhsSymbol));
}
if (!symbolCodes.ContainsKey(lhsSymbol))
{
symbolNames.Add(lhsSymbol);
symbolCodes[lhsSymbol] = symbolNames.Count - 1;
}
if (!reducibleNonterminals.Contains(symbolCodes[lhsSymbol]))
{
reducibleNonterminals.Add(symbolCodes[lhsSymbol]);
}
token = lexer.GetNextToken();
//skipping RANGLE
token = lexer.GetNextToken();
int lhsSymbolCode = symbolCodes[lhsSymbol];
//Zpracujeme výraz na pravé straně, který může sestávat z několika seznamů symbolů oddělenými
//ořítky. Každý z těchto seznamů pak tvoří jedno pravidlo bez ořítek.
while ((token.SymbolCode == CODE_DERIVES) || (token.SymbolCode == CODE_OR))
{
token = lexer.GetNextToken();
List <int> rhsSymbols = new List <int>();
while (token.SymbolCode != CODE_CODE)
{
int rhsSymbolCode = -1;
if (token.SymbolCode == CODE_LANGLE)
{
//skipping LANGLE
token = lexer.GetNextToken();
string rhsSymbol = token.Value;
if (symbolCodes.ContainsKey(rhsSymbol) && symbolCodes[rhsSymbol] < numTerminals)
{
errorMessages.Add(string.Format("{0},{1}: The nonterminal <{2}> shares it's name with a terminal symbol.",
token.LineNumber, token.ColumnNumber, rhsSymbol));
}
if (!symbolCodes.ContainsKey(rhsSymbol))
{
symbolNames.Add(rhsSymbol);
symbolCodes[rhsSymbol] = symbolNames.Count - 1;
}
if (!usedNonterminals.Contains(symbolCodes[rhsSymbol]))
{
usedNonterminals.Add(symbolCodes[rhsSymbol]);
}
token = lexer.GetNextToken();
//skipping RANGLE
token = lexer.GetNextToken();
rhsSymbolCode = symbolCodes[rhsSymbol];
}
else
{
string rhsSymbol = token.Value;
if (!symbolCodes.ContainsKey(rhsSymbol))
{
errorMessages.Add(string.Format("{0},{1}: The terminal '{2}' is used but not defined.",
token.LineNumber, token.ColumnNumber, rhsSymbol));
}
else
{
rhsSymbolCode = symbolCodes[rhsSymbol];
terminalUsed[rhsSymbolCode] = true;
}
token = lexer.GetNextToken();
}
rhsSymbols.Add(rhsSymbolCode);
}
string code = token.Value;
token = lexer.GetNextToken();
productions.Add(new ProductionWithAction(new Production(lhsSymbolCode, rhsSymbols), code));
}
}
}
//ToArray voláme proto, aby se líná metoda Intersect vyhodnotila a nedošlo by pak při vykonávání
//dalšího příkazu k chybě
int[] theGoodOnes = usedNonterminals.Intersect(reducibleNonterminals).ToArray();
usedNonterminals.ExceptWith(theGoodOnes);
reducibleNonterminals.ExceptWith(theGoodOnes);
foreach (int nonterminal in usedNonterminals)
{
warningMessages.Add(string.Format("Warning: The nonterminal <{0}> isn't reducible.",
symbolNames[nonterminal]));
}
foreach (int nonterminal in reducibleNonterminals)
{
warningMessages.Add(string.Format("Warning: The nonterminal <{0}> is defined but never used.", symbolNames[nonterminal]));
}
for (int terminal = 0; terminal < numTerminals; terminal++)
{
if (!terminalUsed[terminal])
{
warningMessages.Add(string.Format("Warning: The terminal '{0}' is defined but never used.", symbolNames[terminal]));
}
}
if (errorMessages.Count > 0)
{
throw new InvalidSpecificationException(errorMessages.Concat(warningMessages));
}
//už máme vše načte a zkontrolováno, teď už jen setřídíme pravidla podle levé strany,
//přečíslujeme je a pro každý neterminál dopočítáme indexy, na kterých začínají pravidla
//s daným neterminálem
Production[] productionsArray = new Production[productions.Count];
productionsArray[0] = productions[0].Production;
string[] actions = new string[productions.Count];
actions[0] = productions[0].Action;
IEnumerable <ProductionWithAction> sortedProductions =
productions.GetRange(1, productions.Count - 1).OrderBy((prod => prod.Production.LHSSymbol));
int k = 1;
foreach (ProductionWithAction productionWithAction in sortedProductions)
{
productionsArray[k] = productionWithAction.Production;
productionsArray[k].ProductionCode = k;
actions[k] = productionWithAction.Action;
k++;
}
int numNonterminals = symbolCodes.Count - numTerminals;
int[] nonterminalProductionOffset = new int[numNonterminals + 1];
int offset = 0;
for (int nonterminal = 0; nonterminal < numNonterminals; nonterminal++)
{
nonterminalProductionOffset[nonterminal] = offset;
while ((offset < productionsArray.Length) &&
(productionsArray[offset].LHSSymbol == numTerminals + nonterminal))
{
offset++;
}
}
nonterminalProductionOffset[nonterminalProductionOffset.Length - 1] = offset;
string[] nonterminalTypes = new string[numNonterminals];
foreach (var typeMapping in typeMappings)
{
nonterminalTypes[symbolCodes[typeMapping.Key] - numTerminals] = typeMapping.Value;
}
//a teď už to jen zabalíme a pošleme
GrammarDefinition grammarDefinition = new GrammarDefinition(symbolNames.ToArray(), productionsArray, nonterminalProductionOffset, numTerminals);
LexerData lexerData = new LexerData(regex, groupSymbolCodes);
GrammarCode grammarCode = new GrammarCode(headerCode, actions, nonterminalTypes, userObjectType);
Grammar grammar = new Grammar(grammarDefinition, lexerData, grammarCode);
return(grammar);
#else
LexerData lexerData;
ParserData parserData;
Grammar.ReadRuntimeDataFromStream(
new MemoryStream(YetAnotherParserGenerator.Properties.Resources.SpecificationGrammar),
out lexerData, out parserData);
GrammarLexer lexer = new GrammarLexer();
Parser parser = new Parser(parserData);
GrammarParserLocals locals = new GrammarParserLocals(specificationPath, out warningMessages);
lexer.SourceString = File.ReadAllText(specificationPath);
return((Grammar)parser.Parse(lexer, locals));
#endif
}
/// <summary>
/// Reads runtime data for lexer/parser construction from a binary Stream.
/// </summary>
/// <param name="inStream">The Stream from which the data shall be read.</param>
/// <param name="lexerData">The LexerData serialized from the Stream.</param>
/// <param name="parserData">The ParserData serialized from the Stream.</param>
public static void ReadRuntimeDataFromStream(Stream inStream, out LexerData lexerData, out ParserData parserData)
{
lexerData = LexerData.FromStream(inStream);
parserData = ParserData.FromStream(inStream);
}
