nodes.cpp

来自「konqueror3 embedded版本, KDE环境下的当家浏览器的嵌入式版」· C++ 代码 · 共 3,000 行 · 第 1/5 页

  return s;
}

// ----------------------------- AccessorNode1 --------------------------------

void AccessorNode1::ref()
{
  Node::ref();
  if ( expr1 )
    expr1->ref();
  if ( expr2 )
    expr2->ref();
}

bool AccessorNode1::deref()
{
  if ( expr1 && expr1->deref() )
    delete expr1;
  if ( expr2 && expr2->deref() )
    delete expr2;
  return Node::deref();
}

// ECMA 11.2.1a
Reference AccessorNode1::evaluateReference(ExecState *exec) const
{
  Value v1 = expr1->evaluate(exec);
  KJS_CHECKEXCEPTIONREFERENCE
  Value v2 = expr2->evaluate(exec);
  KJS_CHECKEXCEPTIONREFERENCE
#ifndef NDEBUG
  // catch errors before being caught in toObject(). better error message.
  if (v1.isA(UndefinedType) || v1.isA(NullType)) {
    UString s = "Attempted to access property on %s object "
                "(result of expression %s)";
        (void)throwError(exec, TypeError, s.cstring().c_str(), v1, this);
    return Reference::makeValueReference(Undefined());
  }
#endif
  Object o = v1.toObject(exec);
  unsigned i;
  if (v2.toUInt32(i))
    return Reference(o, i);
  UString s = v2.toString(exec);
  return Reference(o, Identifier(s));
}

// ----------------------------- AccessorNode2 --------------------------------

void AccessorNode2::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool AccessorNode2::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.2.1b
Reference AccessorNode2::evaluateReference(ExecState *exec) const
{
  Value v = expr->evaluate(exec);
  KJS_CHECKEXCEPTIONREFERENCE
  assert(v.isValid());
#ifndef NDEBUG
  // catch errors before being caught in toObject(). better error message.
  if (v.isA(UndefinedType) || v.isA(NullType)) {
    UString s = "Attempted to access '" + ident.ustring() +
                "' property on %s object (result of expression %s)";
        (void)throwError(exec, TypeError, s.cstring().c_str(), v, this);
    return Reference::makeValueReference(Undefined());
  }
#endif
  Object o = v.toObject(exec);
  return Reference(o, ident);
}

// ----------------------------- ArgumentListNode -----------------------------

void ArgumentListNode::ref()
{
  for (ArgumentListNode *n = this; n; n = n->list) {
    n->Node::ref();
    if (n->expr)
      n->expr->ref();
  }
}

bool ArgumentListNode::deref()
{
  ArgumentListNode *next;
  for (ArgumentListNode *n = this; n; n = next) {
    next = n->list;
    if (n->expr && n->expr->deref())
      delete n->expr;
    if (n != this && n->Node::deref())
      delete n;
  }
  return Node::deref();
}

Value ArgumentListNode::evaluate(ExecState * /*exec*/) const
{
  assert(0);
  return Value(); // dummy, see evaluateList()
}

// ECMA 11.2.4
List ArgumentListNode::evaluateList(ExecState *exec) const
{
  List l;

  for (const ArgumentListNode *n = this; n; n = n->list) {
    Value v = n->expr->evaluate(exec);
    KJS_CHECKEXCEPTIONLIST
    l.append(v);
  }

  return l;
}

// ----------------------------- ArgumentsNode --------------------------------

void ArgumentsNode::ref()
{
  Node::ref();
  if ( list )
    list->ref();
}

bool ArgumentsNode::deref()
{
  if ( list && list->deref() )
    delete list;
  return Node::deref();
}

Value ArgumentsNode::evaluate(ExecState * /*exec*/) const
{
  assert(0);
  return Value(); // dummy, see evaluateList()
}

// ECMA 11.2.4
List ArgumentsNode::evaluateList(ExecState *exec) const
{
  if (!list)
    return List();

  return list->evaluateList(exec);
}

// ----------------------------- NewExprNode ----------------------------------

// ECMA 11.2.2

void NewExprNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
  if ( args )
    args->ref();
}

bool NewExprNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  if ( args && args->deref() )
    delete args;
  return Node::deref();
}

Value NewExprNode::evaluate(ExecState *exec) const
{
  Value v = expr->evaluate(exec);
  KJS_CHECKEXCEPTIONVALUE

  List argList;
  if (args) {
    argList = args->evaluateList(exec);
    KJS_CHECKEXCEPTIONVALUE
  }

  if (v.type() != ObjectType) {
    return throwError(exec, TypeError, "Value %s (result of expression %s) is not an object. Cannot be used with new.", v, expr);
  }

  Object constr = Object(static_cast<ObjectImp*>(v.imp()));
  if (!constr.implementsConstruct()) {
    return throwError(exec, TypeError, "Value %s (result of expression %s) is not a constructor. Cannot be used with new.", v, expr);
  }

  Value res = constr.construct(exec,argList);

  return res;
}

// ----------------------------- FunctionCallNode -----------------------------

void FunctionCallNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
  if ( args )
    args->ref();
}

bool FunctionCallNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  if ( args && args->deref() )
    delete args;
  return Node::deref();
}

// ECMA 11.2.3
Value FunctionCallNode::evaluate(ExecState *exec) const
{
  Reference ref = expr->evaluateReference(exec);
  KJS_CHECKEXCEPTIONVALUE

  List argList = args->evaluateList(exec);
  KJS_CHECKEXCEPTIONVALUE

  Value v = ref.getValue(exec);
  KJS_CHECKEXCEPTIONVALUE

  if (v.type() != ObjectType) {
    return throwError(exec, TypeError, "Value %s (result of expression %s) is not an object. Cannot be called.", v, expr);
  }

  Object func = Object(static_cast<ObjectImp*>(v.imp()));

  if (!func.implementsCall()) {
    return throwError(exec, TypeError, "Object %s (result of expression %s) does not allow calls.", v, expr);
  }

  Value thisVal;
  if (ref.isMutable())
    thisVal = ref.getBase(exec);
  else
    thisVal = Null();

  if (thisVal.type() == ObjectType &&
      Object::dynamicCast(thisVal).inherits(&ActivationImp::info))
    thisVal = Null();

  if (thisVal.type() != ObjectType) {
    // ECMA 11.2.3 says that in this situation the this value should be null.
    // However, section 10.2.3 says that in the case where the value provided
    // by the caller is null, the global object should be used. It also says
    // that the section does not apply to interal functions, but for simplicity
    // of implementation we use the global object anyway here. This guarantees
    // that in host objects you always get a valid object for this.
    // thisVal = Null();
    thisVal = exec->dynamicInterpreter()->globalObject();
  }

  Object thisObj = Object::dynamicCast(thisVal);
  Value result = func.call(exec,thisObj, argList);

  return result;
}

// ----------------------------- PostfixNode ----------------------------------

void PostfixNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool PostfixNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.3
Value PostfixNode::evaluate(ExecState *exec) const
{
  Reference ref = expr->evaluateReference(exec);
  KJS_CHECKEXCEPTIONVALUE
  Value v = ref.getValue(exec);
  double n = v.toNumber(exec);

  double newValue = (oper == OpPlusPlus) ? n + 1 : n - 1;

  ref.putValue(exec, Number(newValue));

  return Number(n);
}

// ----------------------------- DeleteNode -----------------------------------

void DeleteNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool DeleteNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.4.1
Value DeleteNode::evaluate(ExecState *exec) const
{
  Reference ref = expr->evaluateReference(exec);
  KJS_CHECKEXCEPTIONVALUE
  return Boolean(ref.deleteValue(exec));
}

// ----------------------------- VoidNode -------------------------------------

void VoidNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool VoidNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.4.2
Value VoidNode::evaluate(ExecState *exec) const
{
  Value dummy1 = expr->evaluate(exec);
  KJS_CHECKEXCEPTIONVALUE

  return Undefined();
}

// ----------------------------- TypeOfNode -----------------------------------

void TypeOfNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool TypeOfNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.4.3
Value TypeOfNode::evaluate(ExecState *exec) const
{
  const char *s = 0L;
  Reference ref = expr->evaluateReference(exec);
  KJS_CHECKEXCEPTIONVALUE
  if (ref.isMutable()) {
    Value b = ref.getBase(exec);
    if (b.type() == NullType)
      return String("undefined");
  }
  Value v = ref.getValue(exec);
  switch (v.type())
    {
    case UndefinedType:
      s = "undefined";
      break;
    case NullType:
      s = "object";
      break;
    case BooleanType:
      s = "boolean";
      break;
    case NumberType:
      s = "number";
      break;
    case StringType:
      s = "string";
      break;
    default:
      if (v.type() == ObjectType && static_cast<ObjectImp*>(v.imp())->implementsCall())
	s = "function";
      else
	s = "object";
      break;
    }

  return String(s);
}

// ----------------------------- PrefixNode -----------------------------------

void PrefixNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool PrefixNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.4.4 and 11.4.5
Value PrefixNode::evaluate(ExecState *exec) const
{
  Reference ref = expr->evaluateReference(exec);
  KJS_CHECKEXCEPTION
  Value v = ref.getValue(exec);
  double n = v.toNumber(exec);

  double newValue = (oper == OpPlusPlus) ? n + 1 : n - 1;
  Value n2 = Number(newValue);

  ref.putValue(exec,n2);

  return n2;
}

// ----------------------------- UnaryPlusNode --------------------------------

void UnaryPlusNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool UnaryPlusNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.4.6
double UnaryPlusNode::toNumber(ExecState *exec) const
{
  return expr->toNumber(exec);
}

// could go
Value UnaryPlusNode::evaluate(ExecState *exec) const
{
  Value v = expr->evaluate(exec);
  KJS_CHECKEXCEPTIONVALUE

  return Number(v.toNumber(exec)); /* TODO: optimize */
}

// ----------------------------- NegateNode -----------------------------------

void NegateNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool NegateNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.4.7
double NegateNode::toNumber(ExecState *exec) const
{
  return -expr->toNumber(exec);
}

Value NegateNode::evaluate(ExecState *exec) const
{
  Value v = expr->evaluate(exec);
  KJS_CHECKEXCEPTIONVALUE
  double d = -v.toNumber(exec);

  return Number(d);
}

// ----------------------------- BitwiseNotNode -------------------------------

void BitwiseNotNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool BitwiseNotNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.4.8
Value BitwiseNotNode::evaluate(ExecState *exec) const
{
  Value v = expr->evaluate(exec);
  KJS_CHECKEXCEPTIONVALUE
  int i32 = v.toInt32(exec);

  return Number(~i32);
}

// ----------------------------- LogicalNotNode -------------------------------

void LogicalNotNode::ref()
{
  Node::ref();
  if ( expr )
    expr->ref();
}

bool LogicalNotNode::deref()
{
  if ( expr && expr->deref() )
    delete expr;
  return Node::deref();
}

// ECMA 11.4.9
bool LogicalNotNode::toBoolean(ExecState *exec) const
{
  return !expr->toBoolean(exec);
}

// could remove this
Value LogicalNotNode::evaluate(ExecState *exec) const
{
  bool b = expr->toBoolean(exec);
  KJS_CHECKEXCEPTIONVALUE

  return Boolean(!b);
}

// ----------------------------- MultNode -------------------------------------

void MultNode::ref()
{
  Node::ref();
  if ( term1 )
    term1->ref();
  if ( term2 )
    term2->ref();
}

bool MultNode::deref()
{
  if ( term1 && term1->deref() )
    delete term1;
  if ( term2 && term2->deref() )
    delete term2;
  return Node::deref();
}

// ECMA 11.5
Value MultNode::evaluate(ExecState *exec) const
{
  Value v1 = term1->evaluate(exec);
  KJS_CHECKEXCEPTIONVALUE

  Value v2 = term2->evaluate(exec);
  KJS_CHECKEXCEPTIONVALUE

  return mult(exec,v1, v2, oper);
}

// ----------------------------- AddNode --------------------------------------

// factory for an appropriate addition or substraction node
Node* AddNode::create(Node *t1, Node *t2, char op)
{
  // ### many more combinations to check for
  // fold constants