Esempio n. 1
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 void CompSyncSets()
 {
     allSyncSets = new BitArray(terminals.Count);
     allSyncSets[eofSy.n] = true;
     visited = new BitArray(nodes.Count);
     foreach (Symbol sym in nonterminals) {
     curSy = sym;
     CompSync(curSy.graph);
     }
 }
Esempio n. 2
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 void CompFollowSets()
 {
     foreach (Symbol sym in nonterminals) {
     sym.follow = new BitArray(terminals.Count);
     sym.nts = new BitArray(nonterminals.Count);
     }
     gramSy.follow[eofSy.n] = true;
     visited = new BitArray(nodes.Count);
     foreach (Symbol sym in nonterminals) { // get direct successors of nonterminals
     curSy = sym;
     CompFollow(sym.graph);
     }
     foreach (Symbol sym in nonterminals) { // add indirect successors to followers
     visited = new BitArray(nonterminals.Count);
     curSy = sym;
     Complete(sym);
     }
 }
Esempio n. 3
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 void Complete(Symbol sym)
 {
     if (!visited[sym.n]) {
     visited[sym.n] = true;
     foreach (Symbol s in nonterminals) {
         if (sym.nts[s.n]) {
             Complete(s);
             sym.follow.Or(s.follow);
             if (sym == curSy) sym.nts[s.n] = false;
         }
     }
     }
 }
Esempio n. 4
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 public Node NewNode(int typ, Symbol sym, int line)
 {
     Node node = new Node(typ, sym, line);
     node.n = nodes.Count;
     nodes.Add(node);
     return node;
 }
Esempio n. 5
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 public Symbol NewSym(int typ, string name, int line)
 {
     if (name.Length == 2 && name[0] == '"') {
     parser.SemErr("empty token not allowed"); name = "???";
     }
     Symbol sym = new Symbol(typ, name, line);
     switch (typ) {
     case Node.t:  sym.n = terminals.Count; terminals.Add(sym); break;
     case Node.pr: pragmas.Add(sym); break;
     case Node.nt: sym.n = nonterminals.Count; nonterminals.Add(sym); break;
     }
     return sym;
 }
Esempio n. 6
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 public BitArray Expected(Node p, Symbol curSy)
 {
     BitArray s = First(p);
     if (DelGraph(p)) s.Or(curSy.follow);
     return s;
 }
Esempio n. 7
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 // does not look behind resolvers; only called during LL(1) test and in CheckRes
 public BitArray Expected0(Node p, Symbol curSy)
 {
     if (p.typ == Node.rslv) return new BitArray(terminals.Count);
     else return Expected(p, curSy);
 }
Esempio n. 8
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 public void CheckLL1()
 {
     foreach (Symbol sym in nonterminals) {
     curSy = sym;
     CheckAlts(curSy.graph);
     }
 }
Esempio n. 9
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 public void CheckResolvers()
 {
     foreach (Symbol sym in nonterminals) {
     curSy = sym;
     CheckRes(curSy.graph, false);
     }
 }
Esempio n. 10
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 public CNode(Symbol l, Symbol r)
 {
     left = l; right = r;
 }
Esempio n. 11
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        BitArray visited; // mark list for graph traversals

        #endregion Fields

        #region Constructors

        public Tab(Parser parser)
        {
            this.parser = parser;
            trace = parser.trace;
            errors = parser.errors;
            eofSy = NewSym(Node.t, "EOF", 0);
            literals = new Hashtable();
        }
Esempio n. 12
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 void PrintSym(Symbol sym)
 {
     trace.Write("{0,3} {1,-14} {2}", sym.n, Name(sym.name), nTyp[sym.typ]);
     if (sym.attrPos==null) trace.Write(" false "); else trace.Write(" true  ");
     if (sym.typ == Node.nt) {
     trace.Write("{0,5}", Num(sym.graph));
     if (sym.deletable) trace.Write(" true  "); else trace.Write(" false ");
     } else
     trace.Write("            ");
     trace.WriteLine("{0,5}", sym.line);
 }
Esempio n. 13
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        public bool up; // true: "next" leads to successor in enclosing structure

        #endregion Fields

        #region Constructors

        public Node(int typ, Symbol sym, int line)
        {
            this.typ = typ; this.sym = sym; this.line = line;
        }
Esempio n. 14
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 //--------------- check for LL(1) errors ----------------------
 void LL1Error(int cond, Symbol sym)
 {
     string s = "  LL1 warning in " + curSy.name + ": ";
     if (sym != null) s += sym.name + " is ";
     switch (cond) {
     case 1: s += "start of several alternatives"; break;
     case 2: s += "start & successor of deletable structure"; break;
     case 3: s += "an ANY node that matches no symbol"; break;
     case 4: s += "contents of [...] or {...} must not be deletable"; break;
     }
     errors.Warning(s);
 }
Esempio n. 15
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 void GenProductions()
 {
     foreach (Symbol sym in tab.nonterminals) {
     curSy = sym;
     gen.Write("\tvoid {0}(", sym.name);
     CopySourcePart(sym.attrPos, 0);
     gen.WriteLine(") {");
     CopySourcePart(sym.semPos, 2);
     GenCode(sym.graph, 2, new BitArray(tab.terminals.Count));
     gen.WriteLine("\t}"); gen.WriteLine();
     }
 }
Esempio n. 16
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 void GenErrorMsg(int errTyp, Symbol sym)
 {
     errorNr++;
     err.Write("\t\t\tcase " + errorNr + ": s = \"");
     switch (errTyp) {
     case tErr:
         if (sym.name[0] == '"') err.Write(tab.Escape(sym.name) + " expected");
         else err.Write(sym.name + " expected");
         break;
     case altErr: err.Write("invalid " + sym.name); break;
     case syncErr: err.Write("this symbol not expected in " + sym.name); break;
     }
     err.WriteLine("\"; break;");
 }