package FindEscape;public class FindEscape {   static Symbol.Table escEnv = new Symbol.Table();   static int dflag; // flag modalita' debug   // avvia la ricorsione (reso obsoleto da traverseAbsyn)   public FindEscape(Absyn.Exp e, int flag_debug) {      dflag=flag_debug;      traverseExp(0,e);   }   // metodo statico per l'etichettatura (escape) dell'albero della sintassi astratta   public static void traverseAbsyn (Absyn.Exp e, int dflag) {       FindEscape.dflag = dflag;       traverseExp(0,e);   }   // traverseExp   static void traverseExp(int depth, Absyn.Exp e) {      if (e instanceof Absyn.ArrayExp)  traverseExp(depth,(Absyn.ArrayExp)e);      if (e instanceof Absyn.AssignExp) traverseExp(depth,(Absyn.AssignExp)e);      if (e instanceof Absyn.BreakExp)  traverseExp(depth,(Absyn.BreakExp)e);      if (e instanceof Absyn.CallExp)   traverseExp(depth,(Absyn.CallExp)e);      if (e instanceof Absyn.ForExp)    traverseExp(depth,(Absyn.ForExp)e);      if (e instanceof Absyn.IfExp)     traverseExp(depth,(Absyn.IfExp)e);      if (e instanceof Absyn.IntExp)    traverseExp(depth,(Absyn.IntExp)e);      if (e instanceof Absyn.LetExp)    traverseExp(depth,(Absyn.LetExp)e);      if (e instanceof Absyn.NilExp)    traverseExp(depth,(Absyn.NilExp)e);      if (e instanceof Absyn.OpExp)     traverseExp(depth,(Absyn.OpExp)e);      if (e instanceof Absyn.RecordExp) traverseExp(depth,(Absyn.RecordExp)e);      if (e instanceof Absyn.SeqExp)    traverseExp(depth,(Absyn.SeqExp)e);      if (e instanceof Absyn.StringExp) traverseExp(depth,(Absyn.StringExp)e);      if (e instanceof Absyn.VarExp)    traverseExp(depth,(Absyn.VarExp)e);      if (e instanceof Absyn.WhileExp)  traverseExp(depth,(Absyn.WhileExp)e);   }   // traverseVar   static void traverseVar(int depth, Absyn.Var v) {      if (v instanceof Absyn.SimpleVar) { traverseVar(depth,(Absyn.SimpleVar)v); }      if (v instanceof Absyn.FieldVar)  { traverseVar(depth, ((Absyn.FieldVar)v).var); }      if (v instanceof Absyn.SubscriptVar) {          traverseVar(depth ,((Absyn.SubscriptVar)v).var);          traverseExp(depth, ((Absyn.SubscriptVar)v).index);      }   }   // SimpleVar   static void traverseVar(int d,Absyn.SimpleVar v) {      Escape x = (Escape)escEnv.get(v.name);      if (x instanceof VarEscape) {          VarEscape esc = (VarEscape)x;          if (esc.depth < d) {              esc.setEscape();              if (dflag==1) System.out.println("   - [VarEscape] La variabile " + v.name + " e' di tipo escape");          }      }      if (x instanceof FormalEscape) {          FormalEscape esc = (FormalEscape)x;          if (esc.depth < d)  {              esc.setEscape();              if (dflag==1) System.out.println("   - [FormalEscape] La variabile " + v.name + " e' di tipo escape");          }      }   }   // traverseDec   static void traverseDec(int depth, Absyn.Dec d) {      if(d instanceof Absyn.FunctionDec)  traverseDec(depth,(Absyn.FunctionDec)d);      if(d instanceof Absyn.VarDec)       traverseDec(depth,(Absyn.VarDec)d);   }    // EXP    static void traverseExp(int depth, Absyn.ExpList e) {       for(;e!=null;e=e.tail) traverseExp(depth,e.head);     }    static void traverseExp(int depth, Absyn.FieldExpList e) {       for(;e!=null;e=e.tail) traverseExp(depth,e.init);    }    static void traverseExp(int depth, Absyn.ArrayExp e) {       traverseExp(depth,e.init);       traverseExp(depth,e.size);    }    static void traverseExp(int depth, Absyn.AssignExp e) {       traverseVar(depth,e.var);       traverseExp(depth,e.exp);    }    static void traverseExp(int depth, Absyn.BreakExp e) { return; }    static void traverseExp(int depth, Absyn.CallExp e) { traverseExp(depth,e.args); }    static void traverseExp(int depth, Absyn.ForExp e) {       escEnv.beginScope();       traverseDec(depth,e.var);       traverseExp(depth,e.hi);       traverseExp(depth,e.body);       escEnv.endScope();    }    static void traverseExp(int depth, Absyn.IfExp e) {       traverseExp(depth,e.test);       traverseExp(depth,e.thenclause);       if(e.elseclause!=null) traverseExp(depth,e.elseclause);    }    static void traverseExp(int depth, Absyn.IntExp e) { return; }    static void traverseExp(int depth, Absyn.LetExp e) {       escEnv.beginScope();       if(e.decs !=null) traverseDec(depth,e.decs);       traverseExp(depth,e.body);       escEnv.endScope();    }    static void traverseExp(int depth, Absyn.NilExp e) { return; }    static void traverseExp(int depth, Absyn.OpExp e) {       traverseExp(depth,e.left);       traverseExp(depth,e.right);    }    static void traverseExp(int depth, Absyn.RecordExp e) {       if(e.fields!=null) traverseExp(depth,e.fields);    }    static void traverseExp(int depth, Absyn.SeqExp e) {       if(e.list!=null) traverseExp(depth,e.list);    }    static void traverseExp(int depth, Absyn.StringExp e) { return; }    static void traverseExp(int depth, Absyn.VarExp e) { traverseVar(depth,e.var); }    static void traverseExp(int depth, Absyn.WhileExp e) {       traverseExp(depth,e.test);       traverseExp(depth,e.body);    }    // DEC    static void traverseDec(int depth, Absyn.DecList d) {       for(;d!=null;d=d.tail) traverseDec(depth,d.head);    }    static void traverseDec(int depth, Absyn.FunctionDec d) {       // per prendere anche la FunctionDec d.next       for (;d!=null;d=d.next) {          escEnv.beginScope();          // inserisco i parametri nell'ambiente escEnv          for(Absyn.FieldList p=d.params;p!=null;p=p.tail)  escEnv.put(p.name,new FormalEscape(depth+1,p));          traverseExp(depth+1,d.body);          escEnv.endScope();       }    }    static void traverseDec(int depth, Absyn.VarDec d) {       // inserisce la var nell'ambiente escEnv       escEnv.put(d.name,new VarEscape(depth,d));       traverseExp(depth,d.init);    }}