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/* /////////////////////////////////////////////////////////////////////////
* File: stlsoft/conversion/literal_cast.hpp * * Purpose: Compile-time checking for literal conversions. * * Created: 5th September 2003 * Updated: 10th August 2009 * * Home: http://stlsoft.org/
* * Copyright (c) 2003-2009, 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/conversion/literal_cast.hpp
* * \brief [C++ only] Definition of the stlsoft::literal_cast cast class * (\ref group__library__conversion "Conversion" Library). */
#ifndef STLSOFT_INCL_STLSOFT_CONVERSION_HPP_LITERAL_CAST
#define STLSOFT_INCL_STLSOFT_CONVERSION_HPP_LITERAL_CAST
#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
# define STLSOFT_VER_STLSOFT_CONVERSION_HPP_LITERAL_CAST_MAJOR 4
# define STLSOFT_VER_STLSOFT_CONVERSION_HPP_LITERAL_CAST_MINOR 0
# define STLSOFT_VER_STLSOFT_CONVERSION_HPP_LITERAL_CAST_REVISION 4
# define STLSOFT_VER_STLSOFT_CONVERSION_HPP_LITERAL_CAST_EDIT 44
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */
/* /////////////////////////////////////////////////////////////////////////
* Auto-generation and compatibility */
/*
[<[STLSOFT-AUTO:NO-UNITTEST]>] */
/* /////////////////////////////////////////////////////////////////////////
* Includes */
#ifndef STLSOFT_INCL_STLSOFT_H_STLSOFT
# include <stlsoft/stlsoft.h>
#endif /* !STLSOFT_INCL_STLSOFT_H_STLSOFT */
#ifndef STLSOFT_INCL_STLSOFT_UTIL_H_LIMIT_TRAITS
# include <stlsoft/util/limit_traits.h>
#endif /* !STLSOFT_INCL_STLSOFT_UTIL_H_LIMIT_TRAITS */
/* /////////////////////////////////////////////////////////////////////////
* Namespace */
#ifndef _STLSOFT_NO_NAMESPACE
namespace stlsoft { #endif /* _STLSOFT_NO_NAMESPACE */
/* /////////////////////////////////////////////////////////////////////////
* Functions */
#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
# ifdef STLSOFT_CF_64BIT_INT_SUPPORT
typedef ss_sint64_t literal_cast_int_t; typedef ss_uint64_t invalid_int_t; # else /* ? STLSOFT_CF_64BIT_INT_SUPPORT */
typedef ss_sint32_t literal_cast_int_t; typedef ss_uint32_t invalid_int_t; # endif /* STLSOFT_CF_64BIT_INT_SUPPORT */
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */
#if 0
template< ss_typename_param_k T , literal_cast_int_t V > inline T literal_cast() { #if defined(STLSOFT_CF_MEMBER_CONSTANT_SUPPORT)
/* If member constants are supported, we can do compile-time assertions */ const int __literal_cast_value_too_large__ = V <= limit_traits<T>::maximum_value; const int __literal_cast_value_too_small__ = V >= limit_traits<T>::minimum_value;
STLSOFT_STATIC_ASSERT(__literal_cast_value_too_large__); STLSOFT_STATIC_ASSERT(__literal_cast_value_too_small__); #else /* ? STLSOFT_CF_MEMBER_CONSTANT_SUPPORT */
/* If not, then we are restricted to runtime assertions */ const int __literal_cast_value_too_large__ = V <= limit_traits<T>::maximum(); const int __literal_cast_value_too_small__ = V >= limit_traits<T>::minimum();
STLSOFT_MESSAGE_ASSERT("Literal cast value is too large", __literal_cast_value_too_large__); STLSOFT_MESSAGE_ASSERT("Literal cast value is too small", __literal_cast_value_too_small__); #endif /* STLSOFT_CF_MEMBER_CONSTANT_SUPPORT */
return T(V); } #else /* ? 0 */
/** \brief Provides compile-time validation for casts of literal values.
* * \ingroup group__library__conversion * * \param T The type to cast to * \param V The literal value to be cast * \code short s1 = stlsoft::literal_cast<short, 10>(); // Ok: 10 fits into short
short s2 = stlsoft::literal_cast<short, 1000000000>(); // Compile error: value too large for short
\endcode * * \note Thanks to Kevlin Henney (http://www.curbralan.com/) for insights
* into the solution. */ template< ss_typename_param_k T , literal_cast_int_t V > class literal_cast { public: operator T () const { #if defined(STLSOFT_CF_MEMBER_CONSTANT_SUPPORT)
/* If member constants are supported, we can do compile-time assertions */ const int __literal_cast_value_too_large__ = V <= limit_traits<T>::maximum_value; const int __literal_cast_value_too_small__ = V >= limit_traits<T>::minimum_value;
STLSOFT_STATIC_ASSERT(__literal_cast_value_too_large__); STLSOFT_STATIC_ASSERT(__literal_cast_value_too_small__); #else /* ? STLSOFT_CF_MEMBER_CONSTANT_SUPPORT */
/* If not, then we are restricted to runtime assertions */ const int __literal_cast_value_too_large__ = V <= limit_traits<T>::maximum(); const int __literal_cast_value_too_small__ = V >= limit_traits<T>::minimum();
STLSOFT_MESSAGE_ASSERT("Literal cast value is too large", __literal_cast_value_too_large__); STLSOFT_MESSAGE_ASSERT("Literal cast value is too small", __literal_cast_value_too_small__); #endif /* STLSOFT_CF_MEMBER_CONSTANT_SUPPORT */
return T(V); } };
#ifdef STLSOFT_CF_TEMPLATE_PARTIAL_SPECIALISATION_SUPPORT
/** Partial specialisation to
*/ template<literal_cast_int_t V> class literal_cast<invalid_int_t, V> { public: # if 0
literal_cast() { const int STLSOFT_LITERAL_CAST_INVALID_TYPE_WARNING = 0;
STLSOFT_STATIC_ASSERT(STLSOFT_LITERAL_CAST_INVALID_TYPE_WARNING); } # endif /* 0 */
private: operator invalid_int_t () const { const int __literal_cast_cannot_cast_to_largest_unsigned_integer_type__ = 0;
STLSOFT_STATIC_ASSERT(__literal_cast_cannot_cast_to_largest_unsigned_integer_type__);
return 0; }
# if defined(STLSOFT_COMPILER_IS_GCC)
public: static void f() {} # endif /* compiler */
}; #endif /* STLSOFT_CF_TEMPLATE_PARTIAL_SPECIALISATION_SUPPORT */
#endif /* 0 */
////////////////////////////////////////////////////////////////////////////
// Unit-testing
#ifdef STLSOFT_UNITTEST
# include "./unittest/literal_cast_unittest_.h"
#endif /* STLSOFT_UNITTEST */
/* ////////////////////////////////////////////////////////////////////// */
#ifndef _STLSOFT_NO_NAMESPACE
} // namespace stlsoft
#endif /* _STLSOFT_NO_NAMESPACE */
/* ////////////////////////////////////////////////////////////////////// */
#endif /* !STLSOFT_INCL_STLSOFT_CONVERSION_HPP_LITERAL_CAST */
/* ///////////////////////////// end of file //////////////////////////// */
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