/*

 *  This file is part of the KDE libraries

 *  Copyright (C) 1999-2001 Harri Porten (porten@kde.org)

 *  Copyright (C) 2001 Peter Kelly (pmk@post.com)

 *  Copyright (C) 2003 Apple Computer, Inc.

 *

 *  This library is free software; you can redistribute it and/or

 *  modify it under the terms of the GNU Library General Public

 *  License as published by the Free Software Foundation; either

 *  version 2 of the License, or (at your option) any later version.

 *

 *  This library is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 *  Library General Public License for more details.

 *

 *  You should have received a copy of the GNU Library General Public License

 *  along with this library; see the file COPYING.LIB.  If not, write to

 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

 *  Boston, MA 02110-1301, USA.

 *

 */

#ifndef ExecState_H

#define ExecState_H

#include "value.h"

#include "types.h"

#include "CommonIdentifiers.h"

namespace KJS {

    class Context;

    class Interpreter;

    class Interpreter;

    class FunctionImp;

    class GlobalFuncImp;

  /**

   * Represents the current state of script execution. This object allows you

   * obtain a handle the interpreter that is currently executing the script,

   * and also the current execution context.

   */

  class ExecState {

    friend class Interpreter;

    friend class FunctionImp;

    friend class GlobalFuncImp;

  public:

    /**

     * Returns the interpreter associated with this execution state

     *

     * @return The interpreter executing the script

     */

    Interpreter* dynamicInterpreter() const { return m_interpreter; }

    /**

     * Returns the interpreter associated with the current scope's

     * global object

     *

     * @return The interpreter currently in scope

     */

    IMPORT Interpreter* lexicalInterpreter() const;

    /**

     * Returns the execution context associated with this execution state

     *

     * @return The current execution state context

     */

    Context* context() const { return m_context; }

    void setException(JSValue* e) { m_exception = e; }

    void clearException() { m_exception = 0; }

    JSValue* exception() const { return m_exception; }

    JSValue** exceptionSlot() { return &m_exception; }

    bool hadException() const { return !!m_exception; }

    // This is a workaround to avoid accessing the global variables for these identifiers in

    // important property lookup functions, to avoid taking PIC branches in Mach-O binaries

    const CommonIdentifiers& propertyNames() const { return *m_propertyNames; }

  private:

    ExecState(Interpreter* interp, Context* con)

        : m_interpreter(interp)

        , m_context(con)

        , m_exception(0)

        , m_propertyNames(CommonIdentifiers::shared())

    { 

    }

    Interpreter* m_interpreter;

    Context* m_context;

    JSValue* m_exception;

    CommonIdentifiers* m_propertyNames;

  };

} // namespace KJS

#endif // ExecState_H