mirror of
https://github.com/dlang/phobos.git
synced 2025-05-07 11:37:24 +03:00
240 lines
7.5 KiB
C++
240 lines
7.5 KiB
C++
/* /////////////////////////////////////////////////////////////////////////////
|
|
* File: stlsoft_null.h
|
|
*
|
|
* Purpose: NULL_v template class.
|
|
*
|
|
* Created: 8th September 2002
|
|
* Updated: 24th November 2003
|
|
*
|
|
* Author: Matthew Wilson, Synesis Software Pty Ltd.
|
|
*
|
|
* License: (Licensed under the Synesis Software Standard Source License)
|
|
*
|
|
* Copyright (C) 2002-2003, Synesis Software Pty Ltd.
|
|
*
|
|
* All rights reserved.
|
|
*
|
|
* www: http://www.synesis.com.au/stlsoft
|
|
* http://www.stlsoft.org/
|
|
*
|
|
* email: submissions@stlsoft.org for submissions
|
|
* admin@stlsoft.org for other enquiries
|
|
*
|
|
* Redistribution and use in source and binary forms, with or
|
|
* without modification, are permitted provided that the following
|
|
* conditions are met:
|
|
*
|
|
* (i) Redistributions of source code must retain the above
|
|
* copyright notice and contact information, this list of
|
|
* conditions and the following disclaimer.
|
|
*
|
|
* (ii) Any derived versions of this software (howsoever modified)
|
|
* remain the sole property of Synesis Software.
|
|
*
|
|
* (iii) Any derived versions of this software (howsoever modified)
|
|
* remain subject to all these conditions.
|
|
*
|
|
* (iv) Neither the name of Synesis Software nor the names of any
|
|
* subdivisions, employees or agents of Synesis Software, nor the
|
|
* names of any other contributors to this software may be used to
|
|
* endorse or promote products derived from this software without
|
|
* specific prior written permission.
|
|
*
|
|
* This source code is provided by Synesis Software "as is" and any
|
|
* warranties, whether expressed or implied, including, but not
|
|
* limited to, the implied warranties of merchantability and
|
|
* fitness for a particular purpose are disclaimed. In no event
|
|
* shall the Synesis Software 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.
|
|
*
|
|
* ////////////////////////////////////////////////////////////////////////// */
|
|
|
|
|
|
#ifndef _STLSOFT_INCL_H_STLSOFT_NULL
|
|
#define _STLSOFT_INCL_H_STLSOFT_NULL
|
|
|
|
#ifndef __STLSOFT_DOCUMENTATION_SKIP_SECTION
|
|
#define _STLSOFT_VER_H_STLSOFT_NULL_MAJOR 1
|
|
#define _STLSOFT_VER_H_STLSOFT_NULL_MINOR 6
|
|
#define _STLSOFT_VER_H_STLSOFT_NULL_REVISION 1
|
|
#define _STLSOFT_VER_H_STLSOFT_NULL_EDIT 19
|
|
#endif /* !__STLSOFT_DOCUMENTATION_SKIP_SECTION */
|
|
|
|
/* /////////////////////////////////////////////////////////////////////////////
|
|
* Includes
|
|
*/
|
|
|
|
#ifndef _STLSOFT_INCL_H_STLSOFT
|
|
# include "stlsoft.h" // Include the STLSoft root header
|
|
#endif /* !_STLSOFT_INCL_H_STLSOFT */
|
|
|
|
/* _STLSOFT_NULL_v_DEFINED */
|
|
|
|
#ifdef _STLSOFT_NULL_v_DEFINED
|
|
# undef _STLSOFT_NULL_v_DEFINED
|
|
#endif /* _STLSOFT_NULL_v_DEFINED */
|
|
|
|
#define _STLSOFT_NULL_v_DEFINED
|
|
|
|
#if defined(__STLSOFT_COMPILER_IS_DMC)
|
|
//# if __DMC__ < 0x0832
|
|
# undef _STLSOFT_NULL_v_DEFINED
|
|
//# endif /* __DMC__ < 0x0832 */
|
|
#elif defined(__STLSOFT_COMPILER_IS_MSVC) && \
|
|
_MSC_VER < 1310
|
|
# undef _STLSOFT_NULL_v_DEFINED
|
|
#elif defined(__STLSOFT_COMPILER_IS_WATCOM)
|
|
# undef _STLSOFT_NULL_v_DEFINED
|
|
#endif /* compiler */
|
|
|
|
/* _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT */
|
|
|
|
#ifdef _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT
|
|
# undef _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT
|
|
#endif /* _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT */
|
|
|
|
#define _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT
|
|
|
|
#if defined(__STLSOFT_COMPILER_IS_GCC)
|
|
# undef _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT
|
|
#elif defined(__STLSOFT_COMPILER_IS_MWERKS)
|
|
# undef _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT
|
|
#endif /* compiler */
|
|
|
|
/* /////////////////////////////////////////////////////////////////////////////
|
|
* Namespace
|
|
*/
|
|
|
|
#ifndef _STLSOFT_NO_NAMESPACE
|
|
namespace stlsoft
|
|
{
|
|
#endif /* _STLSOFT_NO_NAMESPACE */
|
|
|
|
/* /////////////////////////////////////////////////////////////////////////////
|
|
* Classes
|
|
*/
|
|
|
|
#ifdef _STLSOFT_NULL_v_DEFINED
|
|
|
|
/// \brief Represents a type that can be an active replacement for NULL
|
|
///
|
|
/// This class can act as a replacement for the NULL macro, by being validly
|
|
/// assigned to or equated with pointer types only, as in
|
|
///
|
|
/// int i = NULL; // error
|
|
/// int *p = NULL; // OK
|
|
///
|
|
/// if(i == NULL) {} // error
|
|
/// if(NULL == i) {} // error
|
|
///
|
|
/// if(p == NULL) {} // OK
|
|
/// if(NULL == p) {} // OK
|
|
///
|
|
///
|
|
/// When used via inclusion of the file stlsoft_nulldef.h, the macro NULL is
|
|
/// redefined as NULL_v(), such that expressions containing NULL will be valid
|
|
/// against pointers only.
|
|
struct NULL_v
|
|
{
|
|
// Construction
|
|
public:
|
|
/// Default constructor
|
|
NULL_v()
|
|
{}
|
|
|
|
/// Static creation
|
|
public:
|
|
static NULL_v create()
|
|
{
|
|
return NULL_v();
|
|
}
|
|
|
|
// Conversion
|
|
public:
|
|
/// Implicit conversion operator (convertible to any pointer type)
|
|
///
|
|
/// \param T The type of the pointer to which an instance will be convertible
|
|
template <ss_typename_param_k T>
|
|
operator T *() const
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#ifdef _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT
|
|
/// Implicit conversion operator (convertible to any pointer type)
|
|
///
|
|
/// \param T The type of the pointer to which an instance will be convertible
|
|
template <ss_typename_param_k T2, ss_typename_param_k C>
|
|
operator T2 C::*() const
|
|
{
|
|
return 0;
|
|
}
|
|
#endif /* _STLSOFT_NULL_v_DEFINED_PTR_TO_MEMBER_SUPPORT */
|
|
|
|
/// Evaluates whether an instance of a type is null
|
|
///
|
|
/// \param rhs A reference arbitrary type which will be compared to null
|
|
template <ss_typename_param_k T>
|
|
ss_bool_t equals(T const &rhs) const
|
|
{
|
|
return rhs == 0;
|
|
}
|
|
|
|
// Not to be implemented
|
|
private:
|
|
void operator &() const;
|
|
|
|
NULL_v(NULL_v const &);
|
|
NULL_v const &operator =(NULL_v const &);
|
|
};
|
|
|
|
#if 1
|
|
/// operator == for NULL_v and an arbitrary type
|
|
template <ss_typename_param_k T>
|
|
inline ss_bool_t operator ==(NULL_v const &lhs, T const &rhs)
|
|
{
|
|
return lhs.equals(rhs);
|
|
}
|
|
|
|
/// operator == for an arbitrary type and NULL_v
|
|
template <ss_typename_param_k T>
|
|
inline ss_bool_t operator ==(T const &lhs, NULL_v const &rhs)
|
|
{
|
|
return rhs.equals(lhs);
|
|
}
|
|
|
|
/// operator != for NULL_v and an arbitrary type
|
|
template <ss_typename_param_k T>
|
|
inline ss_bool_t operator !=(NULL_v const &lhs, T const &rhs)
|
|
{
|
|
return !lhs.equals(rhs);
|
|
}
|
|
|
|
/// operator != for an arbitrary type and NULL_v
|
|
template <ss_typename_param_k T>
|
|
inline ss_bool_t operator !=(T const &lhs, NULL_v const &rhs)
|
|
{
|
|
return !rhs.equals(lhs);
|
|
}
|
|
#endif /* 0 */
|
|
|
|
#endif /* _STLSOFT_NULL_v_DEFINED */
|
|
|
|
/* ////////////////////////////////////////////////////////////////////////// */
|
|
|
|
#ifndef _STLSOFT_NO_NAMESPACE
|
|
} // namespace stlsoft
|
|
#endif /* _STLSOFT_NO_NAMESPACE */
|
|
|
|
/* ////////////////////////////////////////////////////////////////////////// */
|
|
|
|
#endif /* !_STLSOFT_INCL_H_STLSOFT_NULL */
|
|
|
|
/* ////////////////////////////////////////////////////////////////////////// */
|