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/* /////////////////////////////////////////////////////////////////////////
* File: stlsoft/obsolete/first_class_promoter.hpp
*
* Purpose: Class template that allows built-in & aggregate types to be treated as 1st-class types.
*
* Created: 8th September 2002
* Updated: 10th August 2009
*
* Home: http://stlsoft.org/
*
* Copyright (c) 2002-2009, 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 stlsoft/obsolete/first_class_promoter.hpp
///
/// Class template that allows built-in & aggregate types to be treated as 1st-class types.
#ifndef STLSOFT_INCL_STLSOFT_OBSOLETE_HPP_FIRST_CLASS_PROMOTER
#define STLSOFT_INCL_STLSOFT_OBSOLETE_HPP_FIRST_CLASS_PROMOTER
#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
# define STLSOFT_VER_STLSOFT_OBSOLETE_HPP_FIRST_CLASS_PROMOTER_MAJOR 4
# define STLSOFT_VER_STLSOFT_OBSOLETE_HPP_FIRST_CLASS_PROMOTER_MINOR 0
# define STLSOFT_VER_STLSOFT_OBSOLETE_HPP_FIRST_CLASS_PROMOTER_REVISION 4
# define STLSOFT_VER_STLSOFT_OBSOLETE_HPP_FIRST_CLASS_PROMOTER_EDIT 51
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */
/* /////////////////////////////////////////////////////////////////////////
* Includes
*/
#ifndef STLSOFT_INCL_STLSOFT_H_STLSOFT
# include <stlsoft/stlsoft.h>
#endif /* !STLSOFT_INCL_STLSOFT_H_STLSOFT */
#ifndef STLSOFT_INCL_STLSOFT_UTIL_HPP_CONSTRAINTS
# include <stlsoft/util/constraints.hpp>
#endif /* !STLSOFT_INCL_STLSOFT_UTIL_HPP_CONSTRAINTS */
#ifndef STLSOFT_INCL_STLSOFT_META_HPP_YESNO
# include <stlsoft/meta/yesno.hpp> // for yes_type, no_type
#endif /* !STLSOFT_INCL_STLSOFT_META_HPP_YESNO */
#ifndef STLSOFT_INCL_STLSOFT_META_HPP_IS_FUNDAMENTAL_TYPE
# include <stlsoft/meta/is_fundamental_type.hpp>
#endif /* !STLSOFT_INCL_STLSOFT_META_HPP_IS_FUNDAMENTAL_TYPE */
#ifndef STLSOFT_INCL_H_STRING
# define STLSOFT_INCL_H_STRING
# include <string.h> // for memset()
#endif /* !STLSOFT_INCL_H_STRING */
/* /////////////////////////////////////////////////////////////////////////
* Namespace
*/
#ifndef _STLSOFT_NO_NAMESPACE
namespace stlsoft
{
#endif /* _STLSOFT_NO_NAMESPACE */
/* /////////////////////////////////////////////////////////////////////////
* TMP worker classes / functions
*/
#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
#ifndef _STLSOFT_NO_NAMESPACE
namespace first_class_promotion
{
#endif /* _STLSOFT_NO_NAMESPACE */
template<ss_bool_t INIT>
struct first_class_promoter_init_traits
{
typedef yes_type type;
};
STLSOFT_TEMPLATE_SPECIALISATION
struct first_class_promoter_init_traits<false>
{
typedef no_type type;
};
template<ss_typename_param_k T>
inline void first_class_promotion_do_init(T *t, yes_type, yes_type)
{
*t = T();
}
template<ss_typename_param_k T>
inline void first_class_promotion_do_init(T *t, yes_type, no_type)
{
::memset(t, 0, sizeof(T));
}
template<ss_typename_param_k T>
inline void first_class_promotion_do_init(T *, no_type, yes_type)
{}
template<ss_typename_param_k T>
inline void first_class_promotion_do_init(T *, no_type, no_type)
{}
template< ss_typename_param_k T
, ss_bool_t INIT
>
struct first_class_promoter_traits
{
typedef ss_typename_type_k first_class_promoter_init_traits<INIT>::type do_init_yesno_type;
#if defined(STLSOFT_COMPILER_IS_BORLAND) && \
__BORLANDC__ < 0x0564
enum { val = is_fundamental_type<T>::value };
typedef first_class_promoter_init_traits<val>::type is_fundamental_yesno_type;
#else /* ? compiler */
typedef ss_typename_type_k first_class_promoter_init_traits<is_fundamental_type<T>::value>::type is_fundamental_yesno_type;
#endif /* compiler */
static void initialise(T *value)
{
first_class_promotion_do_init(value, do_init_yesno_type(), is_fundamental_yesno_type());
}
};
#ifndef _STLSOFT_NO_NAMESPACE
} // namespace first_class_promotion
#endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */
/* /////////////////////////////////////////////////////////////////////////
* Classes
*/
// class first_class_promoter
/** \brief Promotes a basic type to a first-class type
*
* \ingroup group__library__obsolete
*
* This type can be used to promote a basic type (e.g. <code>int</code>) or a type that
* cannot be used as the base of an inheritance relationship (such as a union)
* to first class status.
*
* \param T The basic type
*
*/
template< ss_typename_param_k T
, ss_bool_t INIT = false
>
class first_class_promoter
{
public:
/// The value type
typedef T value_type;
/// The type of the current parameterisation
typedef first_class_promoter<T> class_type;
/// The pointer type
typedef T* pointer;
/// The non-mutating (const) pointer type
typedef T const* const_pointer;
/// The reference type
typedef T& reference;
/// The non-mutating (const) reference type
typedef T const& const_reference;
// Construction
public:
/// Default constructor
///
/// \note The internal member of the \c value_type is <i><b>not</b></i>
/// initialised, for efficiency, if INIT is false (the default)
first_class_promoter()
{
#ifndef _STLSOFT_NO_NAMESPACE
using namespace first_class_promotion;
#endif /* _STLSOFT_NO_NAMESPACE */
first_class_promoter_traits<T, INIT>::initialise(&m_value);
}
/// Copy constructor
first_class_promoter(class_type const& rhs)
: m_value(rhs.m_value)
{}
/// Initialise an instance from an instance of the promoted type
#ifdef STLSOFT_CF_MEMBER_TEMPLATE_CTOR_SUPPORT
template <ss_typename_param_k U>
ss_explicit_k first_class_promoter(U& value)
: m_value(value)
{}
#else /* ? STLSOFT_CF_MEMBER_TEMPLATE_CTOR_SUPPORT */
ss_explicit_k first_class_promoter(value_type const& value)
: m_value(value)
{}
#endif // STLSOFT_CF_MEMBER_TEMPLATE_CTOR_SUPPORT
/// Destructor
~first_class_promoter() stlsoft_throw_0()
{
// This class shouldn't be used for 1st class types, so constrain to
// non-class types, or trivial class types.
//
// It is put in a static assert merely to persuade recalcitrant
// compilers to desist
stlsoft_constraint_must_be_pod(value_type);
// Check the assumption that this veneer is of zero size. The runtime
// assert is included for those compilers that do not implement
// compile-time asserts.
STLSOFT_STATIC_ASSERT(sizeof(class_type) == sizeof(value_type));
#if defined(STLSOFT_COMPILER_IS_WATCOM)
STLSOFT_ASSERT(sizeof(class_type) == sizeof(value_type));
#else /* ? compiler */
STLSOFT_MESSAGE_ASSERT("first_class_promoter used for inappropriate type", sizeof(class_type) == sizeof(value_type));
#endif /* compiler */
}
/// Copy assignment operator
class_type& operator =(class_type const& rhs)
{
m_value = rhs.m_value;
return *this;
}
/// Assignment operator, taking an instance of the promoted type
class_type& operator =(value_type const& value)
{
m_value = value;
return *this;
}
// Accessors
public:
/// Provides a non-mutable (const) reference to the promoted type member
const_reference base_type_value() const
{
return m_value;
}
/// Provides a mutable reference to the promoted type member
reference base_type_value()
{
return m_value;
}
// Operators
public:
/// Implicit conversion operator to a reference to the promoted type member
operator reference()
{
return m_value;
}
/// Implicit conversion operator to a non-mutable (const) reference to the promoted type member
operator const_reference() const
{
return m_value;
}
/// Address-of operator, providing pointer access to the promoted type member
pointer operator &()
{
return &m_value;
}
/// Address-of operator, providing non-mutable (const) pointer access to the promoted type member
const_pointer operator &() const
{
return &m_value;
}
// Members
private:
T m_value;
};
/* ////////////////////////////////////////////////////////////////////// */
#ifndef _STLSOFT_NO_NAMESPACE
} // namespace stlsoft
#endif /* _STLSOFT_NO_NAMESPACE */
/* ////////////////////////////////////////////////////////////////////// */
#endif /* !STLSOFT_INCL_STLSOFT_OBSOLETE_HPP_FIRST_CLASS_PROMOTER */
/* ///////////////////////////// end of file //////////////////////////// */