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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 //////////////////////////// */
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