variant.hpp

新版本TR1的stl

/* /////////////////////////////////////////////////////////////////////////
 * File:        comstl/util/variant.hpp (originally MOVriant.h/.cpp, ::SynesisCom)
 *
 * Purpose:     variant class.
 *
 * Created:     12th December 1996
 * Updated:     29th March 2007
 *
 * Home:        http://stlsoft.org/
 *
 * Copyright (c) 1996-2007, Matthew Wilson and Synesis Software
 * 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(s) of Matthew Wilson and Synesis Software nor the names of
 *   any 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.
 *
 * ////////////////////////////////////////////////////////////////////// */


/** \file comstl/util/variant.hpp
 *
 * \brief [C++ only; requires COM] Definition of the comstl::variant class
 *   (\ref group__library__utility__com "COM Utility" Library).
 */

#ifndef COMSTL_INCL_COMSTL_UTIL_HPP_COMSTL_VARIANT
#define COMSTL_INCL_COMSTL_UTIL_HPP_COMSTL_VARIANT

#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
# define _COMSTL_VER_COMSTL_UTIL_HPP_COMSTL_VARIANT_MAJOR      2
# define _COMSTL_VER_COMSTL_UTIL_HPP_COMSTL_VARIANT_MINOR      2
# define _COMSTL_VER_COMSTL_UTIL_HPP_COMSTL_VARIANT_REVISION   2
# define _COMSTL_VER_COMSTL_UTIL_HPP_COMSTL_VARIANT_EDIT       146
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */

/* /////////////////////////////////////////////////////////////////////////
 * Includes
 */

#ifndef COMSTL_INCL_COMSTL_H_COMSTL
# include <comstl/comstl.h>
#endif /* !COMSTL_INCL_COMSTL_H_COMSTL */
#ifndef COMSTL_INCL_COMSTL_STRING_H_BSTR_FUNCTIONS
# include <comstl/string/bstr_functions.h>
#endif /* !COMSTL_INCL_COMSTL_STRING_H_BSTR_FUNCTIONS */
#ifndef COMSTL_INCL_COMSTL_SHIMS_ACCESS_HPP_STRING
# include <comstl/shims/access/string.hpp>
#endif /* !COMSTL_INCL_COMSTL_SHIMS_ACCESS_HPP_STRING */
#ifdef STLSOFT_CF_EXCEPTION_SUPPORT
# ifndef COMSTL_INCL_COMSTL_ERROR_HPP_EXCEPTIONS
#  include <comstl/error/exceptions.hpp>
# endif /* !COMSTL_INCL_COMSTL_ERROR_HPP_EXCEPTIONS */
#endif /* !STLSOFT_CF_EXCEPTION_SUPPORT */
#ifndef COMSTL_INCL_COMSTL_UTIL_HPP_INTERFACE_TRAITS
# include <comstl/util/interface_traits.hpp>
#endif /* !COMSTL_INCL_COMSTL_UTIL_HPP_INTERFACE_TRAITS */
#ifndef STLSOFT_INCL_STLSOFT_UTIL_HPP_CONSTRAINTS
# include <stlsoft/util/constraints.hpp>
#endif /* !STLSOFT_INCL_STLSOFT_UTIL_HPP_CONSTRAINTS */

/* /////////////////////////////////////////////////////////////////////////
 * Namespace
 */

#ifndef _COMSTL_NO_NAMESPACE
# if defined(_STLSOFT_NO_NAMESPACE) || \
     defined(STLSOFT_DOCUMENTATION_SKIP_SECTION)
/* There is no stlsoft namespace, so must define ::comstl */
namespace comstl
{
# else
/* Define stlsoft::comstl_project */

namespace stlsoft
{

namespace comstl_project
{

# endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !_COMSTL_NO_NAMESPACE */

/* /////////////////////////////////////////////////////////////////////////
 * Classes
 */

/** \brief Facade for the COM VARIANT type
 *
 * \ingroup group__library__utility__com
 *
 * \remarks comstl::variant publicly derives from \c VARIANT as a measure
 *   of expedience, rather than as an act of design sophistication. Any
 *   manual manipulation of the instances, or their member variables, is
 *   at the user's risk. Notwithstanding, this is helped by the fact that
 *   comstl::variant declares no member variables and no virtual member
 *   functions - for most compilers this means that the Empty Derived
 *   Optimisation (see Section 12.4 of Imperfect C++) will apply.
 */
class variant
    : public VARIANT
{
/// Member Types
public:
    typedef variant         class_type;
    typedef cs_bool_t       bool_type;
    typedef cs_size_t       size_type;

/// Conversion
public:
	/** Default constructor
	 *
	 * Initialises the instance
	 *
	 * \post <code>assert(VT_EMPTY == this->vt)</code>
	 *
	 * \exception - Does not throw an exception
	 */
    variant();

	/** Copying constructor
	 *
	 * Initialises the instance with a copy of the given \c VARIANT
	 *
	 * \post <code>assert(rhs == *this)</code>
	 *
	 * \exception comstl::com_exception If the copy fails
	 */
    variant(VARIANT const& rhs);

	/** Copy constructor
	 *
	 * \post <code>assert(rhs == *this)</code>
	 *
	 * \exception comstl::com_exception If the copy fails
	 */
    variant(class_type const& rhs);

	/** Copy assignment operator
	 *
	 * \post <code>assert(rhs == *this)</code>
	 *
	 * \exception comstl::com_exception If the copy fails
	 */
    class_type& operator =(class_type const& rhs);

	/** Conversion constructor
	 *
	 * Initialises the instance with the given boolean value
	 *
	 * \post <code>assert(VT_BOOL == this->vt)</code>
	 * \post <code>assert(b == (VARIANT_TRUE == this->boolVal))</code>
	 *
	 * \exception - Does not throw an exception
	 */
    variant(bool b);

	/** Conversion constructor
	 *
	 * Initialises the instance with the given short value
	 *
	 * \post <code>assert(VT_I2 == this->vt)</code>
	 * \post <code>assert(i == this->iVal)</code>
	 *
	 * \exception - Does not throw an exception
	 */
    variant(short i);

	/** Conversion constructor
	 *
	 * Initialises the instance with the given int value
	 *
	 * \post <code>assert(VT_I4 == this->vt)</code>
	 * \post <code>assert(i == this->lVal)</code>
	 *
	 * \exception - Does not throw an exception
	 */
    variant(int i);

	/** Conversion constructor
	 *
	 * Initialises the instance with the given long value
	 *
	 * \post <code>assert(VT_I4 == this->vt)</code>
	 * \post <code>assert(i == this->lVal)</code>
	 *
	 * \exception - Does not throw an exception
	 */
    variant(long i);

	/** Conversion constructor
	 *
	 * Initialises the instance with the given float value
	 *
	 * \post <code>assert(VT_R4 == this->vt)</code>
	 * \post <code>assert(r == this->fltVal)</code>
	 *
	 * \exception - Does not throw an exception
	 */
    variant(float r);

	/** Conversion constructor
	 *
	 * Initialises the instance with the given double value
	 *
	 * \post <code>assert(VT_R8 == this->vt)</code>
	 * \post <code>assert(r == this->dblVal)</code>
	 *
	 * \exception - Does not throw an exception
	 */
    variant(double r);

	/** Conversion constructor
	 *
	 * Initialises the instance with the given currency (CY) value
	 *
	 * \post <code>assert(VT_CY == this->vt)</code>
	 * \post <code>assert(r == this->cyVal)</code>
	 *
	 * \exception - Does not throw an exception
	 */
    variant(CY cy);
    variant(LPUNKNOWN punk, bool_type bAddRef);
    variant(LPDISPATCH pdisp, bool_type bAddRef);
    variant(cs_char_a_t const* s, int len = -1);
    variant(cs_char_w_t const* s, int len = -1);
    variant(VARIANT const& var, VARTYPE vt);

    ~variant() stlsoft_throw_0()
    {
        stlsoft_constraint_must_be_same_size(class_type, VARIANT);

        ::VariantClear(this);
    }

    void    clear();

/// Operations
public:
    HRESULT     try_conversion_copy(VARIANT const& var, VARTYPE vt);
    HRESULT     try_convert(VARTYPE vt);
    class_type  &convert(VARTYPE vt);

    HRESULT     QueryInterface(REFIID riid, void **ppv) const;

    template <ss_typename_param_k I>
    HRESULT QueryInterfaceValue(I **ppi)
    {
        return QueryInterface(IID_traits<I>::iid(), reinterpret_cast<void**>(ppi));
    }

public:
    void        swap(class_type& rhs);

/// Comparison
public:
    bool_type   equal(class_type const& rhs) const;
    bool_type   equal(VARIANT const& rhs) const;

/// Operators
public:

private:
    static void swap_(VARIANT& lhs, VARIANT& rhs);
    void handle_error_(char const* message, HRESULT hr);
};

/* /////////////////////////////////////////////////////////////////////////
 * String access shims
 */

// No string access shims are defined, because there're already a set
// defined for VARIANT, in comstl/shims/access/string.hpp, which is included
// by this file.

/* /////////////////////////////////////////////////////////////////////////
 * Operators
 */

inline cs_bool_t operator ==(variant const& lhs, variant const& rhs)
{
    return lhs.equal(rhs);
}

inline cs_bool_t operator !=(variant const& lhs, variant const& rhs)
{
    return !operator ==(lhs, rhs);
}

inline cs_bool_t operator ==(variant const& lhs, VARIANT const& rhs)
{
    return lhs.equal(rhs);
}

inline cs_bool_t operator !=(variant const& lhs, VARIANT const& rhs)
{
    return !operator ==(lhs, rhs);
}

inline cs_bool_t operator ==(VARIANT const& lhs, variant const& rhs)
{
    return rhs.equal(lhs);
}

inline cs_bool_t operator !=(VARIANT const& lhs, variant const& rhs)
{
    return !operator ==(lhs, rhs);
}

////////////////////////////////////////////////////////////////////////////
// Unit-testing

#ifdef STLSOFT_UNITTEST
# include "./unittest/variant_unittest_.h"