Merge branch 'master' of ssh://codereview.qt-project.org:29418/playground/v4vm into v4

This is the initial merge of the v4vm JS engine, designed specifically for QML.

The engine is tested on Linux and Mac OS X, works on x86, x86-64 and ARM.

Change-Id: I826b72cfa3d3575007b70d78604080582db568db

Reviewed-by: Lars Knoll <lars.knoll@digia.com>

1 files changed, 2581 insertions, 0 deletions

diff --git a/src/qml/qml/v4vm/qv4v8.h b/src/qml/qml/v4vm/qv4v8.h
new file mode 100644
index 0000000000..bcd6a7fef3
--- /dev/null
+++ b/src/qml/qml/v4vm/qv4v8.h
@@ -0,0 +1,2581 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the V4VM module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+// Copyright 2012 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/** \mainpage V8 API Reference Guide
+ *
+ * V8 is Google's open source JavaScript engine.
+ *
+ * This set of documents provides reference material generated from the
+ * V8 header file, include/v8.h.
+ *
+ * For other documentation see http://code.google.com/apis/v8/
+ */
+
+#ifndef V8_H_
+#define V8_H_
+
+#include "qv4global.h"
+#include "qv4string.h"
+#include <QStack>
+#include <QSharedData>
+
+namespace QQmlJS {
+namespace VM {
+struct Value;
+struct String;
+struct ExecutionEngine;
+struct Object;
+class MemoryManager;
+}
+}
+
+#include <stdint.h>
+
+#define V8EXPORT Q_V4_EXPORT
+
+/**
+ * The v8 JavaScript engine.
+ */
+namespace v8 {
+
+class Context;
+class String;
+class StringObject;
+class Value;
+class Utils;
+class Number;
+class NumberObject;
+class Object;
+class Array;
+class Int32;
+class Uint32;
+class External;
+class Primitive;
+class Boolean;
+class BooleanObject;
+class Integer;
+class Function;
+class Date;
+class ImplementationUtilities;
+class Signature;
+class AccessorSignature;
+template <class T> struct Handle;
+template <class T> class Local;
+template <class T> class Persistent;
+class FunctionTemplate;
+class ObjectTemplate;
+class Data;
+class AccessorInfo;
+class StackTrace;
+class StackFrame;
+class Isolate;
+class TryCatch;
+
+V8EXPORT void *gcProtect(void *handle);
+V8EXPORT void gcProtect(void *memoryManager, void *handle);
+V8EXPORT void gcUnprotect(void *memoryManager, void *handle);
+
+// --- Weak Handles ---
+
+/**
+ * A weak reference callback function.
+ *
+ * This callback should either explicitly invoke Dispose on |object| if
+ * V8 wrapper is not needed anymore, or 'revive' it by invocation of MakeWeak.
+ *
+ * \param object the weak global object to be reclaimed by the garbage collector
+ * \param parameter the value passed in when making the weak global object
+ */
+typedef void (*WeakReferenceCallback)(Persistent<Value> object,
+                                      void* parameter);
+
+
+// --- Handles ---
+
+#define TYPE_CHECK(T, S)                                       \
+  while (false) {                                              \
+    *(static_cast<T* volatile*>(0)) = static_cast<S*>(0);      \
+  }
+
+/**
+ * An object reference managed by the v8 garbage collector.
+ *
+ * All objects returned from v8 have to be tracked by the garbage
+ * collector so that it knows that the objects are still alive.  Also,
+ * because the garbage collector may move objects, it is unsafe to
+ * point directly to an object.  Instead, all objects are stored in
+ * handles which are known by the garbage collector and updated
+ * whenever an object moves.  Handles should always be passed by value
+ * (except in cases like out-parameters) and they should never be
+ * allocated on the heap.
+ *
+ * There are two types of handles: local and persistent handles.
+ * Local handles are light-weight and transient and typically used in
+ * local operations.  They are managed by HandleScopes.  Persistent
+ * handles can be used when storing objects across several independent
+ * operations and have to be explicitly deallocated when they're no
+ * longer used.
+ *
+ * It is safe to extract the object stored in the handle by
+ * dereferencing the handle (for instance, to extract the Object* from
+ * a Handle<Object>); the value will still be governed by a handle
+ * behind the scenes and the same rules apply to these values as to
+ * their handles.
+ */
+
+template <typename T>
+struct Handle;
+
+template <typename T>
+struct HandleOperations
+{
+    static void init(Handle<T> *handle)
+    {
+#if QT_POINTER_SIZE == 8
+        handle->val = quint64(Handle<T>::_Null_Type) << Handle<T>::Tag_Shift;
+#else
+        handle->tag = Handle<T>::_Null_Type;
+        handle->int_32 = 0;
+#endif
+    }
+
+    static void ref(Handle<T> *)
+    {
+    }
+
+    static void deref(Handle<T> *)
+    {
+    }
+
+    static void *protect(Handle<T> *handle)
+    {
+        return gcProtect(handle);
+    }
+
+    static void protect(void *memoryManager, Handle<T> *handle)
+    {
+        gcProtect(memoryManager, handle);
+    }
+
+    static void unProtect(void *memoryManager, Handle<T> *handle)
+    {
+        gcUnprotect(memoryManager, handle);
+    }
+
+    static bool isEmpty(const Handle<T> *handle)
+    {
+        return handle->tag == Handle<T>::_Null_Type;
+    }
+
+    static T *get(const Handle<T> *handle)
+    {
+        return const_cast<T*>(reinterpret_cast<const T*>(handle));
+    }
+};
+
+#define DEFINE_REFCOUNTED_HANDLE_OPERATIONS(Type) \
+    template <> \
+    struct HandleOperations<Type> \
+    { \
+        static void init(Handle<Type> *handle) \
+        { \
+            handle->object = 0; \
+        } \
+    \
+        static void ref(Handle<Type> *handle) \
+        { \
+            if (handle->object) \
+                handle->object->ref.ref(); \
+        } \
+    \
+        static void deref(Handle<Type> *handle) \
+        { \
+            if (handle->object && !handle->object->ref.deref()) { \
+                delete handle->object; \
+                handle->object = 0; \
+            } \
+        } \
+        static void *protect(Handle<Type> *) { return 0; } \
+        static void protect(void *, Handle<Type> *) {} \
+        static void unProtect(void *, Handle<Type> *) {} \
+        static bool isEmpty(const Handle<Type> *handle) \
+        { \
+            return handle->object == 0; \
+        } \
+        static Type *get(const Handle<Type> *handle) \
+        { \
+        return handle->object; \
+        } \
+     \
+    };
+
+template <typename T>
+struct Handle {
+    Handle()
+    {
+        HandleOperations<T>::init(this);
+    }
+    template <typename Other>
+    Handle(const Handle<Other> &that)
+        : val(that.val)
+    {
+        HandleOperations<T>::ref(this);
+    }
+
+    explicit Handle(T *obj)
+    {
+        object = obj;
+        HandleOperations<T>::ref(this);
+    }
+
+    Handle(const Handle<T> &other)
+        : val(other.val)
+    {
+        HandleOperations<T>::ref(this);
+    }
+    Handle<T> &operator=(const Handle<T> &other)
+    {
+        if (this == &other)
+            return *this;
+        HandleOperations<T>::deref(this);
+        this->val = other.val;
+        HandleOperations<T>::ref(this);
+        return *this;
+    }
+    ~Handle()
+    {
+        HandleOperations<T>::deref(this);
+    }
+
+    bool IsEmpty() const { return HandleOperations<T>::isEmpty(this); }
+
+    T *operator->() const { return HandleOperations<T>::get(this); }
+
+    T *get() const { return HandleOperations<T>::get(this); }
+
+    template <typename Source>
+    static Handle<T> Cast(Handle<Source> that)
+    {
+        return that.template As<T>();
+    }
+
+    template <typename Target>
+    Handle<Target> As()
+    {
+        return Handle<Target>(*this);
+    }
+
+    void Clear()
+    {
+        val = 0;
+    }
+
+    template <class S> inline bool operator==(Handle<S> that) const {
+        return val == that.val;
+    }
+    template <class S> inline bool operator!=(Handle<S> that) const {
+        return val != that.val;
+    }
+
+    enum Masks {
+        NotDouble_Mask = 0xfffc0000,
+        Type_Mask = 0xffff8000,
+        Immediate_Mask = NotDouble_Mask | 0x00008000,
+        Tag_Shift = 32
+    };
+
+    enum ValueType {
+        Undefined_Type = Immediate_Mask | 0x00000,
+        Null_Type = Immediate_Mask | 0x10000,
+        Boolean_Type = Immediate_Mask | 0x20000,
+        Integer_Type = Immediate_Mask | 0x30000,
+        Object_Type = NotDouble_Mask | 0x00000,
+        String_Type = NotDouble_Mask | 0x10000
+    };
+
+    enum ImmediateFlags {
+        ConvertibleToInt = Immediate_Mask | 0x1
+    };
+
+    enum ValueTypeInternal {
+        _Undefined_Type = Undefined_Type,
+        _Null_Type = Null_Type | ConvertibleToInt,
+        _Boolean_Type = Boolean_Type | ConvertibleToInt,
+        _Integer_Type = Integer_Type | ConvertibleToInt,
+        _Object_Type = Object_Type,
+        _String_Type = String_Type
+
+    };
+
+    union {
+        T *object;
+        quint64 val;
+        double dbl;
+        struct {
+#if Q_BYTE_ORDER != Q_LITTLE_ENDIAN
+            uint tag;
+#endif
+            union {
+                uint uint_32;
+                int int_32;
+#if QT_POINTER_SIZE == 4
+                T *o;
+#endif
+            };
+#if Q_BYTE_ORDER == Q_LITTLE_ENDIAN
+            uint tag;
+#endif
+        };
+    };
+};
+
+
+/**
+ * A light-weight stack-allocated object handle.  All operations
+ * that return objects from within v8 return them in local handles.  They
+ * are created within HandleScopes, and all local handles allocated within a
+ * handle scope are destroyed when the handle scope is destroyed.  Hence it
+ * is not necessary to explicitly deallocate local handles.
+ */
+template <class T> class Local : public Handle<T> {
+ public:
+  Local() {}
+  template <class S> Local(Local<S> that)
+      : Handle<T>(Handle<T>::Cast(that)) {
+    /**
+     * This check fails when trying to convert between incompatible
+     * handles. For example, converting from a Handle<String> to a
+     * Handle<Number>.
+     */
+    TYPE_CHECK(T, S);
+  }
+  template <class S> Local(S* that) : Handle<T>(that) { }
+  template <class S> static Local<T> Cast(Local<S> that) {
+#ifdef V8_ENABLE_CHECKS
+    // If we're going to perform the type check then we have to check
+    // that the handle isn't empty before doing the checked cast.
+    if (that.IsEmpty()) return Local<T>();
+#endif
+    return Local<T>::New(Handle<T>::Cast(that));
+  }
+
+  template <class S> Local<S> As() {
+    return Local<S>::Cast(*this);
+  }
+
+  /** Create a local handle for the content of another handle.
+   *  The referee is kept alive by the local handle even when
+   *  the original handle is destroyed/disposed.
+   */
+  static Local<T> New(Handle<T> that)
+  {
+      Local<T> result;
+      result.Handle<T>::operator =(that);
+      return result;
+  }
+};
+
+
+/**
+ * An object reference that is independent of any handle scope.  Where
+ * a Local handle only lives as long as the HandleScope in which it was
+ * allocated, a Persistent handle remains valid until it is explicitly
+ * disposed.
+ *
+ * A persistent handle contains a reference to a storage cell within
+ * the v8 engine which holds an object value and which is updated by
+ * the garbage collector whenever the object is moved.  A new storage
+ * cell can be created using Persistent::New and existing handles can
+ * be disposed using Persistent::Dispose.  Since persistent handles
+ * are passed by value you may have many persistent handle objects
+ * that point to the same storage cell.  For instance, if you pass a
+ * persistent handle as an argument to a function you will not get two
+ * different storage cells but rather two references to the same
+ * storage cell.
+ */
+template <class T> class Persistent : public Handle<T> {
+ public:
+  /**
+   * Creates an empty persistent handle that doesn't point to any
+   * storage cell.
+   */
+  Persistent() {}
+  ~Persistent() {
+      HandleOperations<T>::unProtect(m_memoryManager, this);
+  }
+
+  Persistent(const Persistent &other)
+      : Handle<T>(other)
+      , m_memoryManager(other.m_memoryManager)
+  {
+      HandleOperations<T>::protect(m_memoryManager, this);
+  }
+
+  Persistent &operator =(const Persistent &other)
+  {
+      if (&other == this)
+          return *this;
+      HandleOperations<T>::unProtect(m_memoryManager, this);
+      Handle<T>::operator =(other);
+      m_memoryManager = other.m_memoryManager;
+      HandleOperations<T>::protect(m_memoryManager, this);
+      return *this;
+  }
+
+  /**
+   * Creates a persistent handle for the same storage cell as the
+   * specified handle.  This constructor allows you to pass persistent
+   * handles as arguments by value and to assign between persistent
+   * handles.  However, attempting to assign between incompatible
+   * persistent handles, for instance from a Persistent<String> to a
+   * Persistent<Number> will cause a compile-time error.  Assigning
+   * between compatible persistent handles, for instance assigning a
+   * Persistent<String> to a variable declared as Persistent<Value>,
+   * is allowed as String is a subclass of Value.
+   */
+  template <class S> Persistent(Persistent<S> that)
+      : Handle<T>(Handle<T>::Cast(that)) {
+      m_memoryManager = that.m_memoryManager;
+      HandleOperations<T>::protect(m_memoryManager, this);
+  }
+
+  template <class S> Persistent(S* that) : Handle<T>(that)
+  {
+      m_memoryManager = HandleOperations<T>::protect(this);
+  }
+
+  /**
+   * "Casts" a plain handle which is known to be a persistent handle
+   * to a persistent handle.
+   */
+  template <class S> explicit Persistent(Handle<S> that)
+      : Handle<T>(*that)
+  {
+      m_memoryManager = HandleOperations<T>::protect(this);
+  }
+
+  template <class S> static Persistent<T> Cast(Persistent<S> that) {
+    return Persistent<T>(T::Cast(*that));
+  }
+
+  template <class S> Persistent<S> As() {
+    return Persistent<S>::Cast(*this);
+  }
+
+  /**
+   * Creates a new persistent handle for an existing local or
+   * persistent handle.
+   */
+  static Persistent<T> New(Handle<T> that)
+  {
+      Persistent<T> result;
+      result.Handle<T>::operator =(that);
+      result.m_memoryManager = HandleOperations<T>::protect(&result);
+      return result;
+  }
+
+  /**
+   * Releases the storage cell referenced by this persistent handle.
+   * Does not remove the reference to the cell from any handles.
+   * This handle's reference, and any other references to the storage
+   * cell remain and IsEmpty will still return false.
+   */
+  void Dispose() {
+       HandleOperations<T>::unProtect(m_memoryManager, this);
+       m_memoryManager = 0;
+       HandleOperations<T>::deref(this);
+       HandleOperations<T>::init(this);
+  }
+
+  void Dispose(Isolate*) {
+      Dispose();
+  }
+
+  /**
+   * Make the reference to this object weak.  When only weak handles
+   * refer to the object, the garbage collector will perform a
+   * callback to the given V8::WeakReferenceCallback function, passing
+   * it the object reference and the given parameters.
+   */
+  void MakeWeak(void* parameters, WeakReferenceCallback callback);
+public:
+  void *m_memoryManager;
+};
+
+
+ /**
+ * A stack-allocated class that governs a number of local handles.
+ * After a handle scope has been created, all local handles will be
+ * allocated within that handle scope until either the handle scope is
+ * deleted or another handle scope is created.  If there is already a
+ * handle scope and a new one is created, all allocations will take
+ * place in the new handle scope until it is deleted.  After that,
+ * new handles will again be allocated in the original handle scope.
+ *
+ * After the handle scope of a local handle has been deleted the
+ * garbage collector will no longer track the object stored in the
+ * handle and may deallocate it.  The behavior of accessing a handle
+ * for which the handle scope has been deleted is undefined.
+ */
+class V8EXPORT HandleScope {
+ public:
+  HandleScope() {}
+
+  ~HandleScope() {}
+
+  /**
+   * Closes the handle scope and returns the value as a handle in the
+   * previous scope, which is the new current scope after the call.
+   */
+  template <class T> Local<T> Close(Handle<T> value) { return Local<T>::New(value); }
+};
+
+
+// --- Special objects ---
+
+
+/**
+ * The superclass of values and API object templates.
+ */
+class V8EXPORT Data  : public QSharedData {
+};
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(Data)
+
+/**
+ * The origin, within a file, of a script.
+ */
+class V8EXPORT ScriptOrigin {
+public:
+  ScriptOrigin() : m_lineNumber(0), m_columnNumber(0) {}
+
+  ScriptOrigin(
+      Handle<Value> resource_name,
+      Handle<Integer> resource_line_offset = Handle<Integer>(),
+      Handle<Integer> resource_column_offset = Handle<Integer>());
+  Handle<Value> ResourceName() const;
+  Handle<Integer> ResourceLineOffset() const;
+  Handle<Integer> ResourceColumnOffset() const;
+private:
+  QString m_fileName;
+  int m_lineNumber, m_columnNumber;
+  friend class Script;
+};
+
+class ScriptData;
+
+/**
+ * A compiled JavaScript script.
+ */
+class V8EXPORT Script : public QSharedData {
+ public:
+  enum CompileFlags {
+      Default    = 0x00,
+      QmlMode    = 0x01,
+      NativeMode = 0x02
+  };
+
+  /**
+   * Compiles the specified script (context-independent).
+   *
+   * \param source Script source code.
+   * \param origin Script origin, owned by caller, no references are kept
+   *   when New() returns
+   * \param pre_data Pre-parsing data, as obtained by ScriptData::PreCompile()
+   *   using pre_data speeds compilation if it's done multiple times.
+   *   Owned by caller, no references are kept when New() returns.
+   * \param script_data Arbitrary data associated with script. Using
+   *   this has same effect as calling SetData(), but allows data to be
+   *   available to compile event handlers.
+   * \return Compiled script object (context independent; when run it
+   *   will use the currently entered context).
+   */
+  static Local<Script> New(Handle<String> source,
+                           ScriptOrigin* origin = NULL,
+                           ScriptData* pre_data = NULL,
+                           Handle<String> script_data = Handle<String>(),
+                           CompileFlags = Default);
+
+  /**
+   * Compiles the specified script using the specified file name
+   * object (typically a string) as the script's origin.
+   *
+   * \param source Script source code.
+   * \param file_name file name object (typically a string) to be used
+   *   as the script's origin.
+   * \return Compiled script object (context independent; when run it
+   *   will use the currently entered context).
+   */
+  static Local<Script> New(Handle<String> source,
+                           Handle<Value> file_name,
+                           CompileFlags = Default);
+
+  /**
+   * Compiles the specified script (bound to current context).
+   *
+   * \param source Script source code.
+   * \param origin Script origin, owned by caller, no references are kept
+   *   when Compile() returns
+   * \param pre_data Pre-parsing data, as obtained by ScriptData::PreCompile()
+   *   using pre_data speeds compilation if it's done multiple times.
+   *   Owned by caller, no references are kept when Compile() returns.
+   * \param script_data Arbitrary data associated with script. Using
+   *   this has same effect as calling SetData(), but makes data available
+   *   earlier (i.e. to compile event handlers).
+   * \return Compiled script object, bound to the context that was active
+   *   when this function was called.  When run it will always use this
+   *   context.
+   */
+  static Local<Script> Compile(Handle<String> source,
+                               ScriptOrigin* origin = NULL,
+                               ScriptData* pre_data = NULL,
+                               Handle<String> script_data = Handle<String>(),
+                               CompileFlags = Default);
+
+  /**
+   * Compiles the specified script using the specified file name
+   * object (typically a string) as the script's origin.
+   *
+   * \param source Script source code.
+   * \param file_name File name to use as script's origin
+   * \param script_data Arbitrary data associated with script. Using
+   *   this has same effect as calling SetData(), but makes data available
+   *   earlier (i.e. to compile event handlers).
+   * \return Compiled script object, bound to the context that was active
+   *   when this function was called.  When run it will always use this
+   *   context.
+   */
+  static Local<Script> Compile(Handle<String> source,
+                               Handle<Value> file_name,
+                               Handle<String> script_data = Handle<String>(),
+                               CompileFlags = Default);
+
+  /**
+   * Runs the script returning the resulting value.  If the script is
+   * context independent (created using ::New) it will be run in the
+   * currently entered context.  If it is context specific (created
+   * using ::Compile) it will be run in the context in which it was
+   * compiled.
+   */
+  Local<Value> Run();
+  Local<Value> Run(Handle<Object> qml);
+
+  /**
+   * Returns the script id value.
+   */
+  Local<Value> Id();
+
+  /**
+   * Associate an additional data object with the script. This is mainly used
+   * with the debugger as this data object is only available through the
+   * debugger API.
+   */
+  void SetData(Handle<String> data);
+
+private:
+  QString m_script;
+  ScriptOrigin m_origin;
+  CompileFlags m_flags;
+  Handle<Context> m_context;
+};
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(Script)
+
+/**
+ * An error message.
+ */
+class V8EXPORT Message : public QSharedData {
+ public:
+    Message(const QString &message, const QString &resourceName, int lineNumber)
+        : m_message(message), m_resourceName(resourceName), m_lineNumber(lineNumber) {}
+
+  Local<String> Get() const;
+  /**
+   * Returns the resource name for the script from where the function causing
+   * the error originates.
+   */
+  Handle<Value> GetScriptResourceName() const;
+
+  /**
+   * Returns the number, 1-based, of the line where the error occurred.
+   */
+  int GetLineNumber() const;
+
+private:
+  QString m_message;
+  QString m_resourceName;
+  int m_lineNumber;
+};
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(Message)
+
+/**
+ * Representation of a JavaScript stack trace. The information collected is a
+ * snapshot of the execution stack and the information remains valid after
+ * execution continues.
+ */
+class V8EXPORT StackTrace : public QSharedData
+{
+ public:
+  /**
+   * Flags that determine what information is placed captured for each
+   * StackFrame when grabbing the current stack trace.
+   */
+  enum StackTraceOptions {
+    kLineNumber = 1,
+    kColumnOffset = 1 << 1 | kLineNumber,
+    kScriptName = 1 << 2,
+    kFunctionName = 1 << 3,
+    kIsEval = 1 << 4,
+    kIsConstructor = 1 << 5,
+    kScriptNameOrSourceURL = 1 << 6,
+    kOverview = kLineNumber | kColumnOffset | kScriptName | kFunctionName,
+    kDetailed = kOverview | kIsEval | kIsConstructor | kScriptNameOrSourceURL
+  };
+
+  /**
+   * Returns a StackFrame at a particular index.
+   */
+  Local<StackFrame> GetFrame(uint32_t index) const;
+
+  /**
+   * Returns the number of StackFrames.
+   */
+  int GetFrameCount() const;
+
+  /**
+   * Returns StackTrace as a v8::Array that contains StackFrame objects.
+   */
+  Local<Array> AsArray();
+
+  /**
+   * Grab a snapshot of the current JavaScript execution stack.
+   *
+   * \param frame_limit The maximum number of stack frames we want to capture.
+   * \param options Enumerates the set of things we will capture for each
+   *   StackFrame.
+   */
+  static Local<StackTrace> CurrentStackTrace(
+      int frame_limit,
+      StackTraceOptions options = kOverview);
+
+  private:
+  QVector<Local<StackFrame> > frames;
+};
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(StackTrace)
+
+
+/**
+ * A single JavaScript stack frame.
+ */
+class V8EXPORT StackFrame : public QSharedData {
+ public:
+  /**
+   * Returns the number, 1-based, of the line for the associate function call.
+   * This method will return Message::kNoLineNumberInfo if it is unable to
+   * retrieve the line number, or if kLineNumber was not passed as an option
+   * when capturing the StackTrace.
+   */
+  int GetLineNumber() const;
+
+  /**
+   * Returns the 1-based column offset on the line for the associated function
+   * call.
+   * This method will return Message::kNoColumnInfo if it is unable to retrieve
+   * the column number, or if kColumnOffset was not passed as an option when
+   * capturing the StackTrace.
+   */
+  int GetColumn() const;
+
+  /**
+   * Returns the name of the resource that contains the script for the
+   * function for this StackFrame.
+   */
+  Local<String> GetScriptName() const;
+
+  /**
+   * Returns the name of the resource that contains the script for the
+   * function for this StackFrame or sourceURL value if the script name
+   * is undefined and its source ends with //@ sourceURL=... string.
+   */
+  Local<String> GetScriptNameOrSourceURL() const;
+
+  /**
+   * Returns the name of the function associated with this stack frame.
+   */
+  Local<String> GetFunctionName() const;
+
+private:
+  friend class StackTrace;
+  StackFrame(Handle<String> script, Handle<String> function, int line, int column);
+  int m_lineNumber;
+  int m_columnNumber;
+  Persistent<String> m_scriptName;
+  Persistent<String> m_functionName;
+};
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(StackFrame)
+
+// --- Value ---
+
+
+/**
+ * The superclass of all JavaScript values and objects.
+ */
+class V8EXPORT Value {
+ public:
+  /**
+   * Returns true if this value is the undefined value.  See ECMA-262
+   * 4.3.10.
+   */
+  bool IsUndefined() const;
+
+  /**
+   * Returns true if this value is the null value.  See ECMA-262
+   * 4.3.11.
+   */
+  bool IsNull() const;
+
+   /**
+   * Returns true if this value is true.
+   */
+  bool IsTrue() const;
+
+  /**
+   * Returns true if this value is false.
+   */
+  bool IsFalse() const;
+
+  /**
+   * Returns true if this value is an instance of the String type.
+   * See ECMA-262 8.4.
+   */
+  bool IsString() const;
+
+  /**
+   * Returns true if this value is a function.
+   */
+  bool IsFunction() const;
+
+  /**
+   * Returns true if this value is an array.
+   */
+  bool IsArray() const;
+
+  /**
+   * Returns true if this value is an object.
+   */
+  bool IsObject() const;
+
+  /**
+   * Returns true if this value is boolean.
+   */
+  bool IsBoolean() const;
+
+  /**
+   * Returns true if this value is a number.
+   */
+  bool IsNumber() const;
+
+  /**
+   * Returns true if this value is external.
+   */
+  bool IsExternal() const;
+
+  /**
+   * Returns true if this value is a 32-bit signed integer.
+   */
+  bool IsInt32() const;
+
+  /**
+   * Returns true if this value is a 32-bit unsigned integer.
+   */
+  bool IsUint32() const;
+
+  /**
+   * Returns true if this value is a Date.
+   */
+  bool IsDate() const;
+
+  /**
+   * Returns true if this value is a Boolean object.
+   */
+  bool IsBooleanObject() const;
+
+  /**
+   * Returns true if this value is a Number object.
+   */
+  bool IsNumberObject() const;
+
+  /**
+   * Returns true if this value is a String object.
+   */
+  bool IsStringObject() const;
+
+  /**
+   * Returns true if this value is a RegExp.
+   */
+  bool IsRegExp() const;
+
+  /**
+   * Returns true if this value is an Error.
+   */
+  bool IsError() const;
+
+  Local<Boolean> ToBoolean() const;
+  Local<Number> ToNumber() const;
+  Local<String> ToString() const;
+  Local<Object> ToObject() const;
+  Local<Integer> ToInteger() const;
+  Local<Uint32> ToUint32() const;
+  Local<Int32> ToInt32() const;
+
+  /**
+   * Attempts to convert a string to an array index.
+   * Returns an empty handle if the conversion fails.
+   */
+  Local<Uint32> ToArrayIndex() const;
+
+  bool BooleanValue() const;
+  double NumberValue() const;
+  int64_t IntegerValue() const;
+  uint32_t Uint32Value() const;
+  int32_t Int32Value() const;
+
+  /** JS == */
+  bool Equals(Handle<Value> that) const;
+  bool StrictEquals(Handle<Value> that) const;
+
+  static Handle<Value> NewFromInternalValue(quint64 val)
+  {
+      Handle<Value> res;
+      res.val = val;
+      return res;
+  }
+
+  QQmlJS::VM::Value vmValue() const;
+  static Handle<Value> fromVmValue(const QQmlJS::VM::Value &vmValue);
+
+};
+
+
+/**
+ * The superclass of primitive values.  See ECMA-262 4.3.2.
+ */
+class V8EXPORT Primitive : public Value { };
+
+
+/**
+ * A primitive boolean value (ECMA-262, 4.3.14).  Either the true
+ * or false value.
+ */
+class V8EXPORT Boolean : public Primitive {
+ public:
+  bool Value() const;
+  static Handle<Boolean> New(bool value);
+};
+
+
+/**
+ * A JavaScript string value (ECMA-262, 4.3.17).
+ */
+class V8EXPORT String : public Primitive {
+ public:
+  /**
+   * Returns the number of characters in this string.
+   */
+  int Length() const;
+
+
+  /**
+   * Returns the hash of this string.
+   */
+  uint32_t Hash() const;
+
+  struct CompleteHashData {
+    CompleteHashData() : length(0), hash(0), symbol_id(0) {}
+    int length;
+    uint32_t hash;
+    uint32_t symbol_id;
+  };
+
+  /**
+   * Returns the "complete" hash of the string.  This is
+   * all the information about the string needed to implement
+   * a very efficient hash keyed on the string.
+   *
+   * The members of CompleteHashData are:
+   *    length: The length of the string.  Equivalent to Length()
+   *    hash: The hash of the string.  Equivalent to Hash()
+   *    symbol_id: If the string is a sequential symbol, the symbol
+   *        id, otherwise 0.  If the symbol ids of two strings are
+   *        the same (and non-zero) the two strings are identical.
+   *        If the symbol ids are different the strings may still be
+   *        identical, but an Equals() check must be performed.
+   */
+  CompleteHashData CompleteHash() const;
+
+  /**
+   * Compute a hash value for the passed UTF16 string
+   * data.
+   */
+  static uint32_t ComputeHash(uint16_t *string, int length);
+  static uint32_t ComputeHash(char *string, int length);
+
+  /**
+   * Returns true if this string is equal to the external
+   * string data provided.
+   */
+  bool Equals(uint16_t *string, int length);
+  bool Equals(char *string, int length);
+  bool Equals(Handle<Value> that) const {
+    return v8::Value::Equals(that);
+  }
+
+  /**
+   * Write the contents of the string to an external buffer.
+   * If no arguments are given, expects the buffer to be large
+   * enough to hold the entire string and NULL terminator. Copies
+   * the contents of the string and the NULL terminator into the
+   * buffer.
+   *
+   * WriteUtf8 will not write partial UTF-8 sequences, preferring to stop
+   * before the end of the buffer.
+   *
+   * Copies up to length characters into the output buffer.
+   * Only null-terminates if there is enough space in the buffer.
+   *
+   * \param buffer The buffer into which the string will be copied.
+   * \param start The starting position within the string at which
+   * copying begins.
+   * \param length The number of characters to copy from the string.  For
+   *    WriteUtf8 the number of bytes in the buffer.
+   * \param nchars_ref The number of characters written, can be NULL.
+   * \param options Various options that might affect performance of this or
+   *    subsequent operations.
+   * \return The number of characters copied to the buffer excluding the null
+   *    terminator.  For WriteUtf8: The number of bytes copied to the buffer
+   *    including the null terminator (if written).
+   */
+  enum WriteOptions {
+    NO_OPTIONS = 0,
+    HINT_MANY_WRITES_EXPECTED = 1,
+    NO_NULL_TERMINATION = 2,
+    PRESERVE_ASCII_NULL = 4
+  };
+
+  uint16_t GetCharacter(int index);
+
+  // 16-bit character codes.
+  int Write(uint16_t* buffer,
+            int start = 0,
+            int length = -1,
+            int options = NO_OPTIONS) const;
+
+  /**
+   * A zero length string.
+   */
+  static v8::Local<v8::String> Empty();
+  static v8::Local<v8::String> Empty(Isolate* isolate);
+
+  /**
+   * Returns true if the string is external
+   */
+  bool IsExternal() const;
+
+  class V8EXPORT ExternalStringResourceBase {  // NOLINT
+   public:
+    virtual ~ExternalStringResourceBase() {}
+
+   protected:
+    ExternalStringResourceBase() {}
+
+    /**
+     * Internally V8 will call this Dispose method when the external string
+     * resource is no longer needed. The default implementation will use the
+     * delete operator. This method can be overridden in subclasses to
+     * control how allocated external string resources are disposed.
+     */
+    virtual void Dispose() { delete this; }
+
+  };
+
+  /**
+   * An ExternalStringResource is a wrapper around a two-byte string
+   * buffer that resides outside V8's heap. Implement an
+   * ExternalStringResource to manage the life cycle of the underlying
+   * buffer.  Note that the string data must be immutable.
+   */
+  class V8EXPORT ExternalStringResource
+      : public ExternalStringResourceBase {
+   public:
+    /**
+     * Override the destructor to manage the life cycle of the underlying
+     * buffer.
+     */
+    virtual ~ExternalStringResource() {}
+
+    /**
+     * The string data from the underlying buffer.
+     */
+    virtual const uint16_t* data() const = 0;
+
+    /**
+     * The length of the string. That is, the number of two-byte characters.
+     */
+    virtual size_t length() const = 0;
+
+   protected:
+    ExternalStringResource() {}
+  };
+
+  /**
+   * Get the ExternalStringResource for an external string.  Returns
+   * NULL if IsExternal() doesn't return true.
+   */
+  ExternalStringResource* GetExternalStringResource() const;
+
+  static String* Cast(v8::Value* obj);
+
+  /**
+   * Allocates a new string from either UTF-8 encoded or ASCII data.
+   * The second parameter 'length' gives the buffer length.
+   * If the data is UTF-8 encoded, the caller must
+   * be careful to supply the length parameter.
+   * If it is not given, the function calls
+   * 'strlen' to determine the buffer length, it might be
+   * wrong if 'data' contains a null character.
+   */
+  static Local<String> New(const char* data, int length = -1);
+
+  /** Allocates a new string from 16-bit character codes.*/
+  static Local<String> New(const uint16_t* data, int length = -1);
+
+  /** Creates a symbol. Returns one if it exists already.*/
+  static Local<String> NewSymbol(const char* data, int length = -1);
+
+  static Local<String> New(QQmlJS::VM::String *s);
+
+  /**
+   * Creates a new external string using the data defined in the given
+   * resource. When the external string is no longer live on V8's heap the
+   * resource will be disposed by calling its Dispose method. The caller of
+   * this function should not otherwise delete or modify the resource. Neither
+   * should the underlying buffer be deallocated or modified except through the
+   * destructor of the external string resource.
+   */
+  static Local<String> NewExternal(ExternalStringResource* resource);
+
+  /**
+   * Converts an object to an ASCII string.
+   * Useful if you want to print the object.
+   * If conversion to a string fails (eg. due to an exception in the toString()
+   * method of the object) then the length() method returns 0 and the * operator
+   * returns NULL.
+   */
+  class V8EXPORT AsciiValue {
+   public:
+    explicit AsciiValue(Handle<v8::Value> obj);
+    ~AsciiValue() {}
+    char* operator*() { return str.data(); }
+    const char* operator*() const { return str.constData(); }
+    int length() const { return str.length(); }
+   private:
+    QByteArray str;
+
+    // Disallow copying and assigning.
+    AsciiValue(const AsciiValue&);
+    void operator=(const AsciiValue&);
+  };
+
+  /**
+   * Converts an object to a two-byte string.
+   * If conversion to a string fails (eg. due to an exception in the toString()
+   * method of the object) then the length() method returns 0 and the * operator
+   * returns NULL.
+   */
+  class V8EXPORT Value {
+   public:
+    explicit Value(Handle<v8::Value> obj);
+    ~Value() {}
+    uint16_t* operator*() { return (uint16_t *)str.data(); }
+    const uint16_t* operator*() const { return str.utf16(); }
+    int length() const { return str.length(); }
+   private:
+    QString str;
+
+    // Disallow copying and assigning.
+    Value(const Value&);
+    void operator=(const Value&);
+  };
+
+      QString asQString() const;
+      QQmlJS::VM::String *asVMString() const;
+};
+
+
+/**
+ * A JavaScript number value (ECMA-262, 4.3.20)
+ */
+class V8EXPORT Number : public Primitive {
+ public:
+  double Value() const;
+  static Local<Number> New(double value);
+  static Number* Cast(v8::Value* obj);
+};
+
+
+/**
+ * A JavaScript value representing a signed integer.
+ */
+class V8EXPORT Integer : public Number {
+ public:
+  static Local<Integer> New(int32_t value);
+  static Local<Integer> NewFromUnsigned(uint32_t value);
+  static Local<Integer> New(int32_t value, Isolate*);
+  static Local<Integer> NewFromUnsigned(uint32_t value, Isolate*);
+  int64_t Value() const;
+  static Integer* Cast(v8::Value* obj);
+};
+
+
+/**
+ * A JavaScript value representing a 32-bit signed integer.
+ */
+class V8EXPORT Int32 : public Integer {
+ public:
+  int32_t Value() const;
+ private:
+  Int32();
+};
+
+
+/**
+ * A JavaScript value representing a 32-bit unsigned integer.
+ */
+class V8EXPORT Uint32 : public Integer {
+ public:
+  uint32_t Value() const;
+ private:
+  Uint32();
+};
+
+
+enum PropertyAttribute {
+  None       = 0,
+  ReadOnly   = 1 << 0,
+  DontEnum   = 1 << 1,
+  DontDelete = 1 << 2
+};
+
+/**
+ * Accessor[Getter|Setter] are used as callback functions when
+ * setting|getting a particular property. See Object and ObjectTemplate's
+ * method SetAccessor.
+ */
+typedef Handle<Value> (*AccessorGetter)(Local<String> property,
+                                        const AccessorInfo& info);
+
+
+typedef void (*AccessorSetter)(Local<String> property,
+                               Local<Value> value,
+                               const AccessorInfo& info);
+
+
+/**
+ * Access control specifications.
+ *
+ * Some accessors should be accessible across contexts.  These
+ * accessors have an explicit access control parameter which specifies
+ * the kind of cross-context access that should be allowed.
+ *
+ * Additionally, for security, accessors can prohibit overwriting by
+ * accessors defined in JavaScript.  For objects that have such
+ * accessors either locally or in their prototype chain it is not
+ * possible to overwrite the accessor by using __defineGetter__ or
+ * __defineSetter__ from JavaScript code.
+ */
+enum AccessControl {
+  DEFAULT               = 0,
+  ALL_CAN_READ          = 1,
+  ALL_CAN_WRITE         = 1 << 1,
+  PROHIBITS_OVERWRITING = 1 << 2
+};
+
+
+/**
+ * A JavaScript object (ECMA-262, 4.3.3)
+ */
+class V8EXPORT Object : public Value {
+ public:
+    bool Set(Handle<Value> key,
+             Handle<Value> value,
+             PropertyAttribute attribs = None);
+
+  bool Set(uint32_t index,
+                    Handle<Value> value);
+
+  Local<Value> Get(Handle<Value> key);
+
+  Local<Value> Get(uint32_t index);
+
+  // TODO(1245389): Replace the type-specific versions of these
+  // functions with generic ones that accept a Handle<Value> key.
+  bool Has(Handle<String> key);
+
+  bool Delete(Handle<String> key);
+
+  bool Has(uint32_t index);
+
+  bool Delete(uint32_t index);
+
+  bool SetAccessor(Handle<String> name,
+                   AccessorGetter getter,
+                   AccessorSetter setter = 0,
+                   Handle<Value> data = Handle<Value>(),
+                   AccessControl settings = DEFAULT,
+                   PropertyAttribute attribute = None);
+
+  /**
+   * Returns an array containing the names of the enumerable properties
+   * of this object, including properties from prototype objects.  The
+   * array returned by this method contains the same values as would
+   * be enumerated by a for-in statement over this object.
+   */
+  Local<Array> GetPropertyNames();
+
+  /**
+   * This function has the same functionality as GetPropertyNames but
+   * the returned array doesn't contain the names of properties from
+   * prototype objects.
+   */
+  Local<Array> GetOwnPropertyNames();
+
+  /**
+   * Get the prototype object.  This does not skip objects marked to
+   * be skipped by __proto__ and it does not consult the security
+   * handler.
+   */
+  Local<Value> GetPrototype();
+
+  /**
+   * Set the prototype object.  This does not skip objects marked to
+   * be skipped by __proto__ and it does not consult the security
+   * handler.
+   */
+  bool SetPrototype(Handle<Value> prototype);
+
+  /** Gets the value in an internal field. */
+  Local<Value> GetInternalField(int index);
+  /** Sets the value in an internal field. */
+  void SetInternalField(int index, Handle<Value> value);
+
+  class V8EXPORT ExternalResource { // NOLINT
+   public:
+    ExternalResource() {}
+    virtual ~ExternalResource() {}
+
+    virtual void Dispose() { delete this; }
+
+   private:
+    // Disallow copying and assigning.
+    ExternalResource(const ExternalResource&);
+    void operator=(const ExternalResource&);
+  };
+
+  void SetExternalResource(ExternalResource *);
+  ExternalResource *GetExternalResource();
+
+  // Testers for local properties.
+  bool HasOwnProperty(Handle<String> key);
+
+  /**
+   * Returns the identity hash for this object. The current implementation
+   * uses a hidden property on the object to store the identity hash.
+   *
+   * The return value will never be 0. Also, it is not guaranteed to be
+   * unique.
+   */
+  int GetIdentityHash();
+
+  /**
+   * Access hidden properties on JavaScript objects. These properties are
+   * hidden from the executing JavaScript and only accessible through the V8
+   * C++ API. Hidden properties introduced by V8 internally (for example the
+   * identity hash) are prefixed with "v8::".
+   */
+  bool SetHiddenValue(Handle<String> key, Handle<Value> value);
+  Local<Value> GetHiddenValue(Handle<String> key);
+
+  /**
+   * Clone this object with a fast but shallow copy.  Values will point
+   * to the same values as the original object.
+   */
+  Local<Object> Clone();
+
+
+  /**
+   * Checks whether a callback is set by the
+   * ObjectTemplate::SetCallAsFunctionHandler method.
+   * When an Object is callable this method returns true.
+   */
+  bool IsCallable();
+
+  /**
+   * Call an Object as a function if a callback is set by the
+   * ObjectTemplate::SetCallAsFunctionHandler method.
+   */
+  Local<Value> CallAsFunction(Handle<Object> recv,
+                              int argc,
+                              Handle<Value> argv[]);
+
+  /**
+   * Call an Object as a constructor if a callback is set by the
+   * ObjectTemplate::SetCallAsFunctionHandler method.
+   * Note: This method behaves like the Function::NewInstance method.
+   */
+  Local<Value> CallAsConstructor(int argc,
+                                 Handle<Value> argv[]);
+
+  static Local<Object> New();
+  static Object* Cast(Value* obj);
+};
+
+
+/**
+ * An instance of the built-in array constructor (ECMA-262, 15.4.2).
+ */
+class V8EXPORT Array : public Object {
+ public:
+  uint32_t Length() const;
+
+  /**
+   * Creates a JavaScript array with the given length. If the length
+   * is negative the returned array will have length 0.
+   */
+  static Local<Array> New(int length = 0);
+
+  static Array* Cast(Value* obj);
+};
+
+
+/**
+ * A JavaScript function object (ECMA-262, 15.3).
+ */
+class V8EXPORT Function : public Object {
+ public:
+  Local<Object> NewInstance() const;
+  Local<Object> NewInstance(int argc, Handle<Value> argv[]) const;
+  Local<Value> Call(Handle<Object> recv,
+                    int argc,
+                    Handle<Value> argv[]);
+  Handle<Value> GetName() const;
+
+  ScriptOrigin GetScriptOrigin() const;
+  static Function* Cast(Value* obj);
+};
+
+
+/**
+ * An instance of the built-in Date constructor (ECMA-262, 15.9).
+ */
+class V8EXPORT Date : public Object {
+ public:
+  static Local<Value> New(double time);
+
+  /**
+   * A specialization of Value::NumberValue that is more efficient
+   * because we know the structure of this object.
+   */
+  double NumberValue() const;
+
+  static Date* Cast(v8::Value* obj);
+
+  /**
+   * Notification that the embedder has changed the time zone,
+   * daylight savings time, or other date / time configuration
+   * parameters.  V8 keeps a cache of various values used for
+   * date / time computation.  This notification will reset
+   * those cached values for the current context so that date /
+   * time configuration changes would be reflected in the Date
+   * object.
+   *
+   * This API should not be called more than needed as it will
+   * negatively impact the performance of date operations.
+   */
+  static void DateTimeConfigurationChangeNotification();
+
+};
+
+
+/**
+ * A Number object (ECMA-262, 4.3.21).
+ */
+class V8EXPORT NumberObject : public Object {
+ public:
+  static Local<Value> New(double value);
+
+  /**
+   * Returns the Number held by the object.
+   */
+  double NumberValue() const;
+
+  static NumberObject* Cast(v8::Value* obj);
+
+};
+
+
+/**
+ * A Boolean object (ECMA-262, 4.3.15).
+ */
+class V8EXPORT BooleanObject : public Object {
+ public:
+  static Local<Value> New(bool value);
+
+  /**
+   * Returns the Boolean held by the object.
+   */
+  bool BooleanValue() const;
+
+  static BooleanObject* Cast(v8::Value* obj);
+
+};
+
+
+/**
+ * A String object (ECMA-262, 4.3.18).
+ */
+class V8EXPORT StringObject : public Object {
+ public:
+  static Local<Value> New(Handle<String> value);
+
+  /**
+   * Returns the String held by the object.
+   */
+  Local<String> StringValue() const;
+
+  static StringObject* Cast(v8::Value* obj);
+
+};
+
+
+/**
+ * An instance of the built-in RegExp constructor (ECMA-262, 15.10).
+ */
+class V8EXPORT RegExp : public Object {
+ public:
+  /**
+   * Regular expression flag bits. They can be or'ed to enable a set
+   * of flags.
+   */
+  enum Flags {
+    kNone = 0,
+    kGlobal = 1,
+    kIgnoreCase = 2,
+    kMultiline = 4
+  };
+
+  /**
+   * Creates a regular expression from the given pattern string and
+   * the flags bit field. May throw a JavaScript exception as
+   * described in ECMA-262, 15.10.4.1.
+   *
+   * For example,
+   *   RegExp::New(v8::String::New("foo"),
+   *               static_cast<RegExp::Flags>(kGlobal | kMultiline))
+   * is equivalent to evaluating "/foo/gm".
+   */
+  static Local<RegExp> New(Handle<String> pattern,
+                           Flags flags);
+
+  /**
+   * Returns the value of the source property: a string representing
+   * the regular expression.
+   */
+  Local<String> GetSource() const;
+
+  /**
+   * Returns the flags bit field.
+   */
+  Flags GetFlags() const;
+
+  static RegExp* Cast(v8::Value* obj);
+
+};
+
+
+/**
+ * A JavaScript value that wraps a C++ void*.  This type of value is
+ * mainly used to associate C++ data structures with JavaScript
+ * objects.
+ *
+ * The Wrap function V8 will return the most optimal Value object wrapping the
+ * C++ void*. The type of the value is not guaranteed to be an External object
+ * and no assumptions about its type should be made. To access the wrapped
+ * value Unwrap should be used, all other operations on that object will lead
+ * to unpredictable results.
+ */
+class V8EXPORT External : public Value {
+ public:
+  static Local<Value> Wrap(void* data);
+  static void* Unwrap(Handle<Value> obj);
+
+  static Local<External> New(void* value);
+  static External* Cast(Value* obj);
+  void* Value() const;
+};
+
+
+// --- Templates ---
+
+
+/**
+ * The superclass of object and function templates.
+ */
+class V8EXPORT Template : public Data {
+ public:
+  /** Adds a property to each instance created by this template.*/
+  void Set(Handle<String> name, Handle<Value> value,
+           PropertyAttribute attributes = None);
+  void Set(const char* name, Handle<Value> value);
+
+  struct Property {
+      Persistent<String> name;
+      Persistent<Value> value;
+      PropertyAttribute attributes;
+  };
+  QVector<Property> m_properties;
+ };
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(Template)
+
+/**
+ * The argument information given to function call callbacks.  This
+ * class provides access to information about the context of the call,
+ * including the receiver, the number and values of arguments, and
+ * the holder of the function.
+ */
+class V8EXPORT Arguments {
+ public:
+    Arguments(const QQmlJS::VM::Value *args, int argc, const QQmlJS::VM::Value &thisObject, bool isConstructor,
+              const Persistent<Value> &data);
+  int Length() const;
+  Local<Value> operator[](int i) const;
+  Local<Object> This() const;
+  Local<Object> Holder() const;
+  bool IsConstructCall() const;
+  Local<Value> Data() const;
+  Isolate* GetIsolate() const;
+
+private:
+  QVector<Persistent<Value> > m_args;
+  Persistent<Object> m_thisObject;
+  bool m_isConstructor;
+  Persistent<Value> m_data;
+};
+
+
+/**
+ * The information passed to an accessor callback about the context
+ * of the property access.
+ */
+class V8EXPORT AccessorInfo {
+ public:
+  AccessorInfo(const QQmlJS::VM::Value &thisObject, const Persistent<Value> &data);
+  Isolate* GetIsolate() const;
+  Local<Value> Data() const;
+  Local<Object> This() const;
+  Local<Object> Holder() const;
+private:
+  Persistent<Value> m_this;
+  Persistent<Value> m_data;
+};
+
+
+typedef Handle<Value> (*InvocationCallback)(const Arguments& args);
+
+/**
+ * NamedProperty[Getter|Setter] are used as interceptors on object.
+ * See ObjectTemplate::SetNamedPropertyHandler.
+ */
+typedef Handle<Value> (*NamedPropertyGetter)(Local<String> property,
+                                             const AccessorInfo& info);
+
+
+/**
+ * Returns the value if the setter intercepts the request.
+ * Otherwise, returns an empty handle.
+ */
+typedef Handle<Value> (*NamedPropertySetter)(Local<String> property,
+                                             Local<Value> value,
+                                             const AccessorInfo& info);
+
+/**
+ * Returns a non-empty handle if the interceptor intercepts the request.
+ * The result is an integer encoding property attributes (like v8::None,
+ * v8::DontEnum, etc.)
+ */
+typedef Handle<Integer> (*NamedPropertyQuery)(Local<String> property,
+                                              const AccessorInfo& info);
+
+
+/**
+ * Returns a non-empty handle if the deleter intercepts the request.
+ * The return value is true if the property could be deleted and false
+ * otherwise.
+ */
+typedef Handle<Boolean> (*NamedPropertyDeleter)(Local<String> property,
+                                                const AccessorInfo& info);
+
+/**
+ * Returns an array containing the names of the properties the named
+ * property getter intercepts.
+ */
+typedef Handle<Array> (*NamedPropertyEnumerator)(const AccessorInfo& info);
+
+
+/**
+ * Returns the value of the property if the getter intercepts the
+ * request.  Otherwise, returns an empty handle.
+ */
+typedef Handle<Value> (*IndexedPropertyGetter)(uint32_t index,
+                                               const AccessorInfo& info);
+
+
+/**
+ * Returns the value if the setter intercepts the request.
+ * Otherwise, returns an empty handle.
+ */
+typedef Handle<Value> (*IndexedPropertySetter)(uint32_t index,
+                                               Local<Value> value,
+                                               const AccessorInfo& info);
+
+
+/**
+ * Returns a non-empty handle if the interceptor intercepts the request.
+ * The result is an integer encoding property attributes.
+ */
+typedef Handle<Integer> (*IndexedPropertyQuery)(uint32_t index,
+                                                const AccessorInfo& info);
+
+/**
+ * Returns a non-empty handle if the deleter intercepts the request.
+ * The return value is true if the property could be deleted and false
+ * otherwise.
+ */
+typedef Handle<Boolean> (*IndexedPropertyDeleter)(uint32_t index,
+                                                  const AccessorInfo& info);
+
+/**
+ * Returns an array containing the indices of the properties the
+ * indexed property getter intercepts.
+ */
+typedef Handle<Array> (*IndexedPropertyEnumerator)(const AccessorInfo& info);
+
+
+/**
+ * A FunctionTemplate is used to create functions at runtime. There
+ * can only be one function created from a FunctionTemplate in a
+ * context.  The lifetime of the created function is equal to the
+ * lifetime of the context.  So in case the embedder needs to create
+ * temporary functions that can be collected using Scripts is
+ * preferred.
+ *
+ * A FunctionTemplate can have properties, these properties are added to the
+ * function object when it is created.
+ *
+ * A FunctionTemplate has a corresponding instance template which is
+ * used to create object instances when the function is used as a
+ * constructor. Properties added to the instance template are added to
+ * each object instance.
+ *
+ * A FunctionTemplate can have a prototype template. The prototype template
+ * is used to create the prototype object of the function.
+ *
+ * The following example shows how to use a FunctionTemplate:
+ *
+ * \code
+ *    v8::Local<v8::FunctionTemplate> t = v8::FunctionTemplate::New();
+ *    t->Set("func_property", v8::Number::New(1));
+ *
+ *    v8::Local<v8::Template> proto_t = t->PrototypeTemplate();
+ *    proto_t->Set("proto_method", v8::FunctionTemplate::New(InvokeCallback));
+ *    proto_t->Set("proto_const", v8::Number::New(2));
+ *
+ *    v8::Local<v8::ObjectTemplate> instance_t = t->InstanceTemplate();
+ *    instance_t->SetAccessor("instance_accessor", InstanceAccessorCallback);
+ *    instance_t->SetNamedPropertyHandler(PropertyHandlerCallback, ...);
+ *    instance_t->Set("instance_property", Number::New(3));
+ *
+ *    v8::Local<v8::Function> function = t->GetFunction();
+ *    v8::Local<v8::Object> instance = function->NewInstance();
+ * \endcode
+ *
+ * Let's use "function" as the JS variable name of the function object
+ * and "instance" for the instance object created above.  The function
+ * and the instance will have the following properties:
+ *
+ * \code
+ *   func_property in function == true;
+ *   function.func_property == 1;
+ *
+ *   function.prototype.proto_method() invokes 'InvokeCallback'
+ *   function.prototype.proto_const == 2;
+ *
+ *   instance instanceof function == true;
+ *   instance.instance_accessor calls 'InstanceAccessorCallback'
+ *   instance.instance_property == 3;
+ * \endcode
+ *
+ * A FunctionTemplate can inherit from another one by calling the
+ * FunctionTemplate::Inherit method.  The following graph illustrates
+ * the semantics of inheritance:
+ *
+ * \code
+ *   FunctionTemplate Parent  -> Parent() . prototype -> { }
+ *     ^                                                  ^
+ *     | Inherit(Parent)                                  | .__proto__
+ *     |                                                  |
+ *   FunctionTemplate Child   -> Child()  . prototype -> { }
+ * \endcode
+ *
+ * A FunctionTemplate 'Child' inherits from 'Parent', the prototype
+ * object of the Child() function has __proto__ pointing to the
+ * Parent() function's prototype object. An instance of the Child
+ * function has all properties on Parent's instance templates.
+ *
+ * Let Parent be the FunctionTemplate initialized in the previous
+ * section and create a Child FunctionTemplate by:
+ *
+ * \code
+ *   Local<FunctionTemplate> parent = t;
+ *   Local<FunctionTemplate> child = FunctionTemplate::New();
+ *   child->Inherit(parent);
+ *
+ *   Local<Function> child_function = child->GetFunction();
+ *   Local<Object> child_instance = child_function->NewInstance();
+ * \endcode
+ *
+ * The Child function and Child instance will have the following
+ * properties:
+ *
+ * \code
+ *   child_func.prototype.__proto__ == function.prototype;
+ *   child_instance.instance_accessor calls 'InstanceAccessorCallback'
+ *   child_instance.instance_property == 3;
+ * \endcode
+ */
+class V8EXPORT FunctionTemplate : public Template {
+ public:
+  /** Creates a function template.*/
+  static Local<FunctionTemplate> New(
+      InvocationCallback callback = 0,
+      Handle<Value> data = Handle<Value>());
+  /** Returns the unique function instance in the current execution context.*/
+  Local<Function> GetFunction();
+
+  /** Get the InstanceTemplate. */
+  Local<ObjectTemplate> InstanceTemplate();
+
+  /**
+   * A PrototypeTemplate is the template used to create the prototype object
+   * of the function created by this template.
+   */
+  Local<ObjectTemplate> PrototypeTemplate();
+
+private:
+  FunctionTemplate(InvocationCallback callback, Handle<Value> data);
+  friend class V4V8Function;
+  InvocationCallback m_callback;
+  Persistent<Value> m_data;
+  Local<ObjectTemplate> m_instanceTemplate;
+  Local<ObjectTemplate> m_prototypeTemplate;
+};
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(FunctionTemplate)
+
+
+/**
+ * An ObjectTemplate is used to create objects at runtime.
+ *
+ * Properties added to an ObjectTemplate are added to each object
+ * created from the ObjectTemplate.
+ */
+class V8EXPORT ObjectTemplate : public Template {
+ public:
+  /** Creates an ObjectTemplate. */
+  static Local<ObjectTemplate> New();
+
+  /** Creates a new instance of this template.*/
+  Local<Object> NewInstance();
+
+  /**
+   * Sets an accessor on the object template.
+   *
+   * Whenever the property with the given name is accessed on objects
+   * created from this ObjectTemplate the getter and setter callbacks
+   * are called instead of getting and setting the property directly
+   * on the JavaScript object.
+   *
+   * \param name The name of the property for which an accessor is added.
+   * \param getter The callback to invoke when getting the property.
+   * \param setter The callback to invoke when setting the property.
+   * \param data A piece of data that will be passed to the getter and setter
+   *   callbacks whenever they are invoked.
+   * \param settings Access control settings for the accessor. This is a bit
+   *   field consisting of one of more of
+   *   DEFAULT = 0, ALL_CAN_READ = 1, or ALL_CAN_WRITE = 2.
+   *   The default is to not allow cross-context access.
+   *   ALL_CAN_READ means that all cross-context reads are allowed.
+   *   ALL_CAN_WRITE means that all cross-context writes are allowed.
+   *   The combination ALL_CAN_READ | ALL_CAN_WRITE can be used to allow all
+   *   cross-context access.
+   * \param attribute The attributes of the property for which an accessor
+   *   is added.
+   * \param signature The signature describes valid receivers for the accessor
+   *   and is used to perform implicit instance checks against them. If the
+   *   receiver is incompatible (i.e. is not an instance of the constructor as
+   *   defined by FunctionTemplate::HasInstance()), an implicit TypeError is
+   *   thrown and no callback is invoked.
+   */
+  void SetAccessor(Handle<String> name,
+                   AccessorGetter getter,
+                   AccessorSetter setter = 0,
+                   Handle<Value> data = Handle<Value>(),
+                   AccessControl settings = DEFAULT,
+                   PropertyAttribute attribute = None);
+
+  /**
+   * Sets a named property handler on the object template.
+   *
+   * Whenever a named property is accessed on objects created from
+   * this object template, the provided callback is invoked instead of
+   * accessing the property directly on the JavaScript object.
+   *
+   * \param getter The callback to invoke when getting a property.
+   * \param setter The callback to invoke when setting a property.
+   * \param query The callback to invoke to check if a property is present,
+   *   and if present, get its attributes.
+   * \param deleter The callback to invoke when deleting a property.
+   * \param enumerator The callback to invoke to enumerate all the named
+   *   properties of an object.
+   * \param data A piece of data that will be passed to the callbacks
+   *   whenever they are invoked.
+   */
+  void SetNamedPropertyHandler(NamedPropertyGetter getter,
+                               NamedPropertySetter setter = 0,
+                               NamedPropertyQuery query = 0,
+                               NamedPropertyDeleter deleter = 0,
+                               NamedPropertyEnumerator enumerator = 0,
+                               Handle<Value> data = Handle<Value>());
+  void SetFallbackPropertyHandler(NamedPropertyGetter getter,
+                                  NamedPropertySetter setter = 0,
+                                  NamedPropertyQuery query = 0,
+                                  NamedPropertyDeleter deleter = 0,
+                                  NamedPropertyEnumerator enumerator = 0,
+                                  Handle<Value> data = Handle<Value>());
+
+  /**
+   * Sets an indexed property handler on the object template.
+   *
+   * Whenever an indexed property is accessed on objects created from
+   * this object template, the provided callback is invoked instead of
+   * accessing the property directly on the JavaScript object.
+   *
+   * \param getter The callback to invoke when getting a property.
+   * \param setter The callback to invoke when setting a property.
+   * \param query The callback to invoke to check if an object has a property.
+   * \param deleter The callback to invoke when deleting a property.
+   * \param enumerator The callback to invoke to enumerate all the indexed
+   *   properties of an object.
+   * \param data A piece of data that will be passed to the callbacks
+   *   whenever they are invoked.
+   */
+  void SetIndexedPropertyHandler(IndexedPropertyGetter getter,
+                                 IndexedPropertySetter setter = 0,
+                                 IndexedPropertyQuery query = 0,
+                                 IndexedPropertyDeleter deleter = 0,
+                                 IndexedPropertyEnumerator enumerator = 0,
+                                 Handle<Value> data = Handle<Value>());
+
+  /**
+   * Gets the number of internal fields for objects generated from
+   * this template.
+   */
+  int InternalFieldCount();
+
+  /**
+   * Sets the number of internal fields for objects generated from
+   * this template.
+   */
+  void SetInternalFieldCount(int value);
+
+  /**
+   * Sets whether the object can store an "external resource" object.
+   */
+  bool HasExternalResource();
+  void SetHasExternalResource(bool value);
+
+  /**
+   * Mark object instances of the template as using the user object
+   * comparison callback.
+   */
+  void MarkAsUseUserObjectComparison();
+
+  struct Accessor {
+      Persistent<Value> getter;
+      Persistent<Value> setter;
+      Persistent<String> name;
+      PropertyAttribute attribute;
+  };
+
+  QVector<Accessor> m_accessors;
+
+  NamedPropertyGetter m_namedPropertyGetter;
+  NamedPropertySetter m_namedPropertySetter;
+  NamedPropertyQuery m_namedPropertyQuery;
+  NamedPropertyDeleter m_namedPropertyDeleter;
+  NamedPropertyEnumerator m_namedPropertyEnumerator;
+  Persistent<Value> m_namedPropertyData;
+
+  NamedPropertyGetter m_fallbackPropertyGetter;
+  NamedPropertySetter m_fallbackPropertySetter;
+  NamedPropertyQuery m_fallbackPropertyQuery;
+  NamedPropertyDeleter m_fallbackPropertyDeleter;
+  NamedPropertyEnumerator m_fallbackPropertyEnumerator;
+  Persistent<Value> m_fallbackPropertyData;
+
+  IndexedPropertyGetter m_indexedPropertyGetter;
+  IndexedPropertySetter m_indexedPropertySetter;
+  IndexedPropertyQuery m_indexedPropertyQuery;
+  IndexedPropertyDeleter m_indexedPropertyDeleter;
+  IndexedPropertyEnumerator m_indexedPropertyEnumerator;
+  Persistent<Value> m_indexedPropertyData;
+
+  bool m_useUserComparison;
+  private:
+  ObjectTemplate();
+ };
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(ObjectTemplate)
+
+// --- Statics ---
+
+
+Handle<Primitive> V8EXPORT Undefined();
+Handle<Primitive> V8EXPORT Null();
+Handle<Boolean> V8EXPORT True();
+Handle<Boolean> V8EXPORT False();
+
+inline Handle<Primitive> Undefined(Isolate*) { return Undefined(); }
+inline Handle<Primitive> Null(Isolate*) { return Null(); }
+inline Handle<Boolean> True(Isolate*) { return True(); }
+inline Handle<Boolean> False(Isolate*) { return False(); }
+
+
+
+// --- Exceptions ---
+
+
+/**
+ * Schedules an exception to be thrown when returning to JavaScript.  When an
+ * exception has been scheduled it is illegal to invoke any JavaScript
+ * operation; the caller must return immediately and only after the exception
+ * has been handled does it become legal to invoke JavaScript operations.
+ */
+Handle<Value> V8EXPORT ThrowException(Handle<Value> exception);
+
+/**
+ * Create new error objects by calling the corresponding error object
+ * constructor with the message.
+ */
+class V8EXPORT Exception {
+ public:
+  static Local<Value> ReferenceError(Handle<String> message);
+  static Local<Value> SyntaxError(Handle<String> message);
+  static Local<Value> TypeError(Handle<String> message);
+  static Local<Value> Error(Handle<String> message);
+};
+
+
+// --- User Object Comparison Callback ---
+typedef bool (*UserObjectComparisonCallback)(Local<Object> lhs,
+                                             Local<Object> rhs);
+
+// --- Garbage Collection Callbacks ---
+
+/**
+ * Applications can register callback functions which will be called
+ * before and after a garbage collection.  Allocations are not
+ * allowed in the callback functions, you therefore cannot manipulate
+ * objects (set or delete properties for example) since it is possible
+ * such operations will result in the allocation of objects.
+ */
+enum GCType {
+  kGCTypeScavenge = 1 << 0,
+  kGCTypeMarkSweepCompact = 1 << 1,
+  kGCTypeAll = kGCTypeScavenge | kGCTypeMarkSweepCompact
+};
+
+enum GCCallbackFlags {
+  kNoGCCallbackFlags = 0,
+  kGCCallbackFlagCompacted = 1 << 0
+};
+
+typedef void (*GCPrologueCallback)(GCType type, GCCallbackFlags flags);
+typedef void (*GCCallback)();
+
+
+
+/**
+ * Isolate represents an isolated instance of the V8 engine.  V8
+ * isolates have completely separate states.  Objects from one isolate
+ * must not be used in other isolates.  When V8 is initialized a
+ * default isolate is implicitly created and entered.  The embedder
+ * can create additional isolates and use them in parallel in multiple
+ * threads.  An isolate can be entered by at most one thread at any
+ * given time.  The Locker/Unlocker API must be used to synchronize.
+ */
+class V8EXPORT Isolate {
+ public:
+    Isolate();
+    ~Isolate();
+  /**
+   * Stack-allocated class which sets the isolate for all operations
+   * executed within a local scope.
+   */
+  class V8EXPORT Scope {
+   public:
+    explicit Scope(Isolate* isolate) : isolate_(isolate) {
+      isolate->Enter();
+    }
+
+    ~Scope() { isolate_->Exit(); }
+
+   private:
+    Isolate* const isolate_;
+
+    // Prevent copying of Scope objects.
+    Scope(const Scope&);
+    Scope& operator=(const Scope&);
+  };
+
+  /**
+   * Creates a new isolate.  Does not change the currently entered
+   * isolate.
+   *
+   * When an isolate is no longer used its resources should be freed
+   * by calling Dispose().  Using the delete operator is not allowed.
+   */
+  static Isolate* New();
+
+  /**
+   * Returns the entered isolate for the current thread or NULL in
+   * case there is no current isolate.
+   */
+  static Isolate* GetCurrent();
+
+  /**
+   * Methods below this point require holding a lock (using Locker) in
+   * a multi-threaded environment.
+   */
+
+  /**
+   * Sets this isolate as the entered one for the current thread.
+   * Saves the previously entered one (if any), so that it can be
+   * restored when exiting.  Re-entering an isolate is allowed.
+   */
+  void Enter();
+
+  /**
+   * Exits this isolate by restoring the previously entered one in the
+   * current thread.  The isolate may still stay the same, if it was
+   * entered more than once.
+   *
+   * Requires: this == Isolate::GetCurrent().
+   */
+  void Exit();
+
+  /**
+   * Disposes the isolate.  The isolate must not be entered by any
+   * thread to be disposable.
+   */
+  void Dispose();
+
+  /**
+   * Associate embedder-specific data with the isolate
+   */
+  void SetData(void* data);
+
+  /**
+   * Retrieve embedder-specific data from the isolate.
+   * Returns NULL if SetData has never been called.
+   */
+  void* GetData();
+
+  Context *GetCurrentContext() { return m_contextStack.top(); }
+  void setException(const QQmlJS::VM::Value &ex);
+
+  private:
+      friend class Context;
+      friend class TryCatch;
+      Isolate* m_lastIsolate;
+      QStack<Context*> m_contextStack;
+      TryCatch *tryCatch;
+};
+
+
+/**
+ * Container class for static utility functions.
+ */
+class V8EXPORT V8 {
+ public:
+
+  /**
+   * Sets V8 flags from a string.
+   */
+  static void SetFlagsFromString(const char* str, int length);
+
+  /** Callback for user object comparisons */
+  static void SetUserObjectComparisonCallbackFunction(UserObjectComparisonCallback);
+
+  /**
+   * Enables the host application to receive a notification before a
+   * garbage collection.  Allocations are not allowed in the
+   * callback function, you therefore cannot manipulate objects (set
+   * or delete properties for example) since it is possible such
+   * operations will result in the allocation of objects. It is possible
+   * to specify the GCType filter for your callback. But it is not possible to
+   * register the same callback function two times with different
+   * GCType filters.
+   */
+  static void AddGCPrologueCallback(
+      GCPrologueCallback callback, GCType gc_type_filter = kGCTypeAll);
+
+  /**
+   * This function removes callback which was installed by
+   * AddGCPrologueCallback function.
+   */
+  static void RemoveGCPrologueCallback(GCPrologueCallback callback);
+
+  /**
+   * Allows the host application to declare implicit references between
+   * the objects: if |parent| is alive, all |children| are alive too.
+   * After each garbage collection, all implicit references
+   * are removed.  It is intended to be used in the before-garbage-collection
+   * callback function.
+   */
+  static void AddImplicitReferences(Persistent<Object> parent,
+                                    Persistent<Value>* children,
+                                    size_t length);
+
+  /**
+   * Initializes from snapshot if possible. Otherwise, attempts to
+   * initialize from scratch.  This function is called implicitly if
+   * you use the API without calling it first.
+   */
+  static bool Initialize();
+
+  /**
+   * Releases any resources used by v8 and stops any utility threads
+   * that may be running.  Note that disposing v8 is permanent, it
+   * cannot be reinitialized.
+   *
+   * It should generally not be necessary to dispose v8 before exiting
+   * a process, this should happen automatically.  It is only necessary
+   * to use if the process needs the resources taken up by v8.
+   */
+  static bool Dispose();
+
+  /**
+   * Optional notification that the embedder is idle.
+   * V8 uses the notification to reduce memory footprint.
+   * This call can be used repeatedly if the embedder remains idle.
+   * Returns true if the embedder should stop calling IdleNotification
+   * until real work has been done.  This indicates that V8 has done
+   * as much cleanup as it will be able to do.
+   *
+   * The hint argument specifies the amount of work to be done in the function
+   * on scale from 1 to 1000. There is no guarantee that the actual work will
+   * match the hint.
+   */
+  static bool IdleNotification(int hint = 1000);
+
+  /**
+   * Optional notification that the system is running low on memory.
+   * V8 uses these notifications to attempt to free memory.
+   */
+  static void LowMemoryNotification();
+};
+
+/**
+ * An external exception handler.
+ */
+class V8EXPORT TryCatch {
+ public:
+  /**
+   * Creates a new try/catch block and registers it with v8.
+   */
+  TryCatch();
+
+  /**
+   * Unregisters and deletes this try/catch block.
+   */
+  ~TryCatch();
+
+  /**
+   * Returns true if an exception has been caught by this try/catch block.
+   */
+  bool HasCaught() const;
+
+  /**
+   * Throws the exception caught by this TryCatch in a way that avoids
+   * it being caught again by this same TryCatch.  As with ThrowException
+   * it is illegal to execute any JavaScript operations after calling
+   * ReThrow; the caller must return immediately to where the exception
+   * is caught.
+   */
+  Handle<Value> ReThrow();
+
+  /**
+   * Returns the exception caught by this try/catch block.  If no exception has
+   * been caught an empty handle is returned.
+   *
+   * The returned handle is valid until this TryCatch block has been destroyed.
+   */
+  Local<Value> Exception() const;
+
+  /**
+   * Returns the message associated with this exception.  If there is
+   * no message associated an empty handle is returned.
+   *
+   * The returned handle is valid until this TryCatch block has been
+   * destroyed.
+   */
+  Local<v8::Message> Message() const;
+
+  /**
+   * Clears any exceptions that may have been caught by this try/catch block.
+   * After this method has been called, HasCaught() will return false.
+   *
+   * It is not necessary to clear a try/catch block before using it again; if
+   * another exception is thrown the previously caught exception will just be
+   * overwritten.  However, it is often a good idea since it makes it easier
+   * to determine which operation threw a given exception.
+   */
+  void Reset();
+
+private:
+    friend class Isolate;
+    TryCatch *parent;
+    bool hasCaughtException;
+    Local<Value> exception;
+};
+
+
+// --- Context ---
+class V8EXPORT ExtensionConfiguration;
+
+/**
+ * A sandboxed execution context with its own set of built-in objects
+ * and functions.
+ */
+class V8EXPORT Context : public QSharedData {
+ public:
+    Context();
+    ~Context();
+
+    static Local<Context> Adopt(Context *p)
+    {
+        Local<Context> l;
+        l.object = p;
+        l.object->ref.ref();
+        return l;
+    }
+  /**
+   * Returns the global proxy object or global object itself for
+   * detached contexts.
+   *
+   * Global proxy object is a thin wrapper whose prototype points to
+   * actual context's global object with the properties like Object, etc.
+   * This is done that way for security reasons (for more details see
+   * https://wiki.mozilla.org/Gecko:SplitWindow).
+   *
+   * Please note that changes to global proxy object prototype most probably
+   * would break VM---v8 expects only global object as a prototype of
+   * global proxy object.
+   *
+   * If DetachGlobal() has been invoked, Global() would return actual global
+   * object until global is reattached with ReattachGlobal().
+   */
+  Local<Object> Global();
+
+  /** Creates a new context.
+   *
+   * Returns a persistent handle to the newly allocated context. This
+   * persistent handle has to be disposed when the context is no
+   * longer used so the context can be garbage collected.
+   *
+   * \param extensions An optional extension configuration containing
+   * the extensions to be installed in the newly created context.
+   *
+   * \param global_template An optional object template from which the
+   * global object for the newly created context will be created.
+   *
+   * \param global_object An optional global object to be reused for
+   * the newly created context. This global object must have been
+   * created by a previous call to Context::New with the same global
+   * template. The state of the global object will be completely reset
+   * and only object identify will remain.
+   */
+  static Persistent<Context> New(
+      ExtensionConfiguration* extensions = NULL,
+      Handle<ObjectTemplate> global_template = Handle<ObjectTemplate>(),
+      Handle<Value> global_object = Handle<Value>());
+
+  /** Returns the context that is on the top of the stack. */
+  static Local<Context> GetCurrent();
+
+  /**
+   * Returns the context of the calling JavaScript code.  That is the
+   * context of the top-most JavaScript frame.  If there are no
+   * JavaScript frames an empty handle is returned.
+   */
+  static Local<Context> GetCalling();
+  static Local<Object> GetCallingQmlGlobal();
+  static Local<Value> GetCallingScriptData();
+
+  /**
+   * Enter this context.  After entering a context, all code compiled
+   * and run is compiled and run in this context.  If another context
+   * is already entered, this old context is saved so it can be
+   * restored when the new context is exited.
+   */
+  void Enter();
+
+  /**
+   * Exit this context.  Exiting the current context restores the
+   * context that was in place when entering the current context.
+   */
+  void Exit();
+
+  /**
+   * Associate an additional data object with the context. This is mainly used
+   * with the debugger to provide additional information on the context through
+   * the debugger API.
+   */
+  void SetData(Handle<Value> data);
+  Local<Value> GetData();
+
+  /**
+   * Stack-allocated class which sets the execution context for all
+   * operations executed within a local scope.
+   */
+  class Scope {
+   public:
+    explicit Scope(Handle<Context> context) : context_(context) {
+      context_->Enter();
+    }
+    ~Scope() { context_->Exit(); }
+   private:
+    Handle<Context> context_;
+  };
+
+  QQmlJS::VM::ExecutionEngine *GetEngine();
+
+private:
+  Context* m_lastContext;
+  struct Private;
+  Private *d;
+  friend class Value;
+  friend class Script;
+  friend class Object;
+  friend class Function;
+};
+
+DEFINE_REFCOUNTED_HANDLE_OPERATIONS(Context)
+
+template<typename T>
+void Persistent<T>::MakeWeak(void* parameters, WeakReferenceCallback callback)
+{
+    Q_UNUSED(parameters);
+    Q_UNUSED(callback);
+
+    Q_UNIMPLEMENTED();
+}
+
+
+
+}  // namespace v8
+
+
+#undef V8EXPORT
+#undef TYPE_CHECK
+
+
+#endif  // V8_H_