aspect PrettyPrint {

  // *** API ***

  // A contextfree grammar has a String attribute *pp()*
  // which is a prettyprinted representation of the grammar
  syn String CFG.pp();
  
  
  // *** Implementation ***
  
  eq CFG.pp() {
    StringBuffer sb = new StringBuffer();
    for (int i = 0; i< getNumRule(); i++) {
      sb.append(getRule(i).pp());
    }
    return sb.toString();
  }
  
  syn String Rule.pp() {
    StringBuffer sb = new StringBuffer();
    sb.append(getNDecl().pp());
    sb.append(" ::= ");
    if (getNumProd() > 0) 
      sb.append(getProd(0).pp());
    for (int i = 1; i< getNumProd(); i++) {
      sb.append("|" + getProd(i).pp());
    }
    sb.append(";\n");
    return sb.toString();
  }
  
  syn String Prod.pp() {
    StringBuffer sb = new StringBuffer();
    
    for (int i = 0; i< getNumSymbol(); i++) {
      sb.append(" " + getSymbol(i).pp());
    }
    return sb.toString();
  }
  
  syn String Symbol.pp();
  
  eq Terminal.pp() = getTERMINAL();
  
  eq NUse.pp() = getID();
  
  syn String NDecl.pp() = getID();
}