public Grammar(Grammar g)
{
_nonterminals = new List<Nonterminal>(g.Nonterminals);
_terminals = new List<Terminal>(g.Terminals);
_rules = new List<Rule>(g.Rules);
_distinguishedSymbol = new Nonterminal(g.DistinguishedSymbol);
_vanishingSymbols = new List<Nonterminal>(g.VanishingSymbols);
}
public bool analyze(String s, Analyzer analyzer)
{
if (analyzer is DescentRecursiveAnalyzer)
_grammar = analyzer.getGrammar();
List<Symbol> symbolInput = _grammar.verifyString(s);
bool result = analyzer.analyzeSymbolString(symbolInput);
_history = analyzer.getHistory();
return result;
}
private State _state; // текущее состояние
#endregion Fields
#region Constructors
public DescendingBacktrackAnalyzer(Grammar g)
: base(g)
{
_state = State.NORMAL;
_position = 0;
_currentString = new Stack<Symbol>();
_history = new Stack<HistoryItem>();
_orderedAlternatives = new Dictionary<string, List<Alternative>>();
_inputString = new List<Symbol>();
_altIdx = 0;
_noMoreConfigurations = false;
_configurationHistory = new StringBuilder();
}
public override Grammar read(string fname)
{
Grammar g = new Grammar();
StreamReader sr = new StreamReader(fname);
string line;
// читаем нетерминалы
List<string> nonTerms = readBlock(sr);
nonTerms.ForEach(s => g.Nonterminals.Add(new Nonterminal(s)));
// читаем терминалы
List<string> terms = readBlock(sr);
terms.ForEach(s => g.Terminals.Add(new Terminal(s)));
// читаем правила
List<string> rules = readBlock(sr);
g.Rules = parseRules(rules, terms, nonTerms);
// читаем аксиому
string axiom = readAxiom(sr);
if (!nonTerms.Contains(axiom))
throw new FormatException("Некорректный формат файла.");
g.DistinguishedSymbol = new Nonterminal(axiom);
sr.Close();
g.findVanishingSymbols();
return g;
}
public DescentRecursiveAnalyzer()
{
_grammar = new Grammar
{
Nonterminals = new List<Nonterminal> { new Nonterminal("S"), new Nonterminal("A"), new Nonterminal("B") },
Terminals = new List<Terminal> { new Terminal("true"), new Terminal("false"), new Terminal("&"), new Terminal("!"), new Terminal("~"), new Terminal("a") },
Rules = new List<Rule>
{
new Rule { Left = new Nonterminal("S"), Right = new List<Symbol>{ new Terminal("true"), new Nonterminal("A") } }, // R1
new Rule { Left = new Nonterminal("S"), Right = new List<Symbol>{ new Terminal("false"), new Nonterminal("A") } }, // R2
new Rule { Left = new Nonterminal("S"), Right = new List<Symbol>{ new Terminal("a"), new Nonterminal("A") } }, // R3
new Rule { Left = new Nonterminal("S"), Right = new List<Symbol>{ new Terminal("~"), new Nonterminal("B") } }, // R4
new Rule { Left = new Nonterminal("A"), Right = new List<Symbol>{ new Terminal("&"), new Nonterminal("S") } }, // R5
new Rule { Left = new Nonterminal("A"), Right = new List<Symbol>{ new Terminal("!"), new Nonterminal("S") } }, // R6
new Rule { Left = new Nonterminal("A"), Right = new List<Symbol>{ new EmptySymbol()} }, // R7
new Rule { Left = new Nonterminal("B"), Right = new List<Symbol>{new Terminal("true"), new Nonterminal("A") } }, // R8
new Rule { Left = new Nonterminal("B"), Right = new List<Symbol>{new Terminal("false"), new Nonterminal("A") } }, // R9
new Rule { Left = new Nonterminal("B"), Right = new List<Symbol>{new Terminal("a"), new Nonterminal("A") } } // R10
},
DistinguishedSymbol = new Nonterminal("S")
};
_history = new StringBuilder();
}
public void setGrammar(Grammar g)
{
_grammar = new Grammar(g);
}
public void loadGrammar(string fileName)
{
TextGrammarReader reader = new TextGrammarReader();
_grammar = reader.read(fileName);
}
public Analyzer(Grammar g)
{
_grammar = g;
}
