mirror of
https://github.com/ecency/ecency-mobile.git
synced 2024-12-04 07:05:20 +03:00
79 lines
2.8 KiB
C++
79 lines
2.8 KiB
C++
// boost polymorphic_pointer_cast.hpp header file ----------------------------------------------//
|
|
// (C) Copyright Boris Rasin and Antony Polukhin 2014-2015.
|
|
// Distributed under the Boost
|
|
// Software License, Version 1.0. (See accompanying file
|
|
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|
|
|
// See http://www.boost.org/libs/conversion for Documentation.
|
|
|
|
#ifndef BOOST_CONVERSION_POLYMORPHIC_POINTER_CAST_HPP
|
|
#define BOOST_CONVERSION_POLYMORPHIC_POINTER_CAST_HPP
|
|
|
|
# include <boost/config.hpp>
|
|
# include <boost/assert.hpp>
|
|
# include <boost/pointer_cast.hpp>
|
|
# include <boost/throw_exception.hpp>
|
|
# include <boost/utility/declval.hpp>
|
|
# ifdef BOOST_NO_CXX11_DECLTYPE
|
|
# include <boost/typeof/typeof.hpp>
|
|
# endif
|
|
|
|
#ifdef BOOST_HAS_PRAGMA_ONCE
|
|
# pragma once
|
|
#endif
|
|
|
|
namespace boost
|
|
{
|
|
// See the documentation for descriptions of how to choose between
|
|
// static_pointer_cast<>, dynamic_pointer_cast<>, polymorphic_pointer_cast<> and polymorphic_pointer_downcast<>
|
|
|
|
// polymorphic_pointer_downcast --------------------------------------------//
|
|
|
|
// BOOST_ASSERT() checked polymorphic downcast. Crosscasts prohibited.
|
|
// Supports any type with static_pointer_cast/dynamic_pointer_cast functions:
|
|
// built-in pointers, std::shared_ptr, boost::shared_ptr, boost::intrusive_ptr, etc.
|
|
|
|
// WARNING: Because this cast uses BOOST_ASSERT(), it violates
|
|
// the One Definition Rule if used in multiple translation units
|
|
// where BOOST_DISABLE_ASSERTS, BOOST_ENABLE_ASSERT_HANDLER
|
|
// NDEBUG are defined inconsistently.
|
|
|
|
// Contributed by Boris Rasin
|
|
|
|
namespace detail
|
|
{
|
|
template <typename Target, typename Source>
|
|
struct dynamic_pointer_cast_result
|
|
{
|
|
#ifdef BOOST_NO_CXX11_DECLTYPE
|
|
BOOST_TYPEOF_NESTED_TYPEDEF_TPL(nested, dynamic_pointer_cast<Target>(boost::declval<Source>()))
|
|
typedef typename nested::type type;
|
|
#else
|
|
typedef decltype(dynamic_pointer_cast<Target>(boost::declval<Source>())) type;
|
|
#endif
|
|
};
|
|
}
|
|
|
|
template <typename Target, typename Source>
|
|
inline typename detail::dynamic_pointer_cast_result<Target, Source>::type
|
|
polymorphic_pointer_downcast (const Source& x)
|
|
{
|
|
BOOST_ASSERT(dynamic_pointer_cast<Target> (x) == x);
|
|
return static_pointer_cast<Target> (x);
|
|
}
|
|
|
|
template <typename Target, typename Source>
|
|
inline typename detail::dynamic_pointer_cast_result<Target, Source>::type
|
|
polymorphic_pointer_cast (const Source& x)
|
|
{
|
|
typename detail::dynamic_pointer_cast_result<Target, Source>::type tmp
|
|
= dynamic_pointer_cast<Target> (x);
|
|
if ( !tmp ) boost::throw_exception( std::bad_cast() );
|
|
|
|
return tmp;
|
|
}
|
|
|
|
} // namespace boost
|
|
|
|
#endif // BOOST_CONVERSION_POLYMORPHIC_POINTER_CAST_HPP
|