ecency-mobile/ios/Pods/boost-for-react-native/boost/python/data_members.hpp

319 lines
9.8 KiB
C++

// Copyright David Abrahams 2002.
// 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)
#ifndef DATA_MEMBERS_DWA2002328_HPP
# define DATA_MEMBERS_DWA2002328_HPP
# include <boost/python/detail/prefix.hpp>
# include <boost/python/handle.hpp>
# include <boost/python/return_value_policy.hpp>
# include <boost/python/return_by_value.hpp>
# include <boost/python/return_internal_reference.hpp>
# include <boost/python/make_function.hpp>
# include <boost/python/converter/builtin_converters.hpp>
# include <boost/python/detail/indirect_traits.hpp>
# include <boost/python/detail/not_specified.hpp>
# include <boost/python/detail/value_arg.hpp>
# include <boost/type_traits/add_const.hpp>
# include <boost/type_traits/add_reference.hpp>
# include <boost/type_traits/is_member_pointer.hpp>
# if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3003))
# include <boost/type_traits/remove_cv.hpp>
# endif
# include <boost/mpl/eval_if.hpp>
# include <boost/mpl/if.hpp>
# include <boost/mpl/vector/vector10.hpp>
# include <boost/detail/workaround.hpp>
namespace boost { namespace python {
//
// This file defines the make_getter and make_setter function
// families, which are responsible for turning pointers, references,
// and pointers-to-data-members into callable Python objects which
// can be used for attribute access on wrapped classes.
//
namespace detail
{
// A small function object which handles the getting and setting of
// data members.
template <class Data, class Class>
struct member
{
public:
member(Data Class::*which) : m_which(which) {}
Data& operator()(Class& c) const
{
return c.*m_which;
}
void operator()(Class& c, typename value_arg<Data>::type d) const
{
c.*m_which = d;
}
private:
Data Class::*m_which;
};
// A small function object which handles the getting and setting of
// non-member objects.
template <class Data>
struct datum
{
public:
datum(Data *which) : m_which(which) {}
Data& operator()() const
{
return *m_which;
}
void operator()(typename value_arg<Data>::type d) const
{
*m_which = d;
}
private:
Data *m_which;
};
//
// Helper metafunction for determining the default CallPolicy to use
// for attribute access. If T is a [reference to a] class type X
// whose conversion to python would normally produce a new copy of X
// in a wrapped X class instance (as opposed to types such as
// std::string, which are converted to native Python types, and
// smart pointer types which produce a wrapped class instance of the
// pointee type), to-python conversions will attempt to produce an
// object which refers to the original C++ object, rather than a
// copy. See default_member_getter_policy for rationale.
//
template <class T>
struct default_getter_by_ref
: mpl::and_<
mpl::bool_<
to_python_value<
typename value_arg<T>::type
>::uses_registry
>
, indirect_traits::is_reference_to_class<
typename value_arg<T>::type
>
>
{
};
// Metafunction computing the default CallPolicy to use for reading
// data members
//
// If it's a regular class type (not an object manager or other
// type for which we have to_python specializations, use
// return_internal_reference so that we can do things like
// x.y.z = 1
// and get the right result.
template <class T>
struct default_member_getter_policy
: mpl::if_<
default_getter_by_ref<T>
, return_internal_reference<>
, return_value_policy<return_by_value>
>
{};
// Metafunction computing the default CallPolicy to use for reading
// non-member data.
template <class T>
struct default_datum_getter_policy
: mpl::if_<
default_getter_by_ref<T>
, return_value_policy<reference_existing_object>
, return_value_policy<return_by_value>
>
{};
//
// make_getter helper function family -- These helpers to
// boost::python::make_getter are used to dispatch behavior. The
// third argument is a workaround for a CWPro8 partial ordering bug
// with pointers to data members. It should be convertible to
// mpl::true_ iff the first argument is a pointer-to-member, and
// mpl::false_ otherwise. The fourth argument is for compilers
// which don't support partial ordering at all and should always be
// passed 0L.
//
#if BOOST_WORKAROUND(__EDG_VERSION__, <= 238)
template <class D, class P>
inline object make_getter(D& d, P& p, mpl::false_, ...);
#endif
// Handle non-member pointers with policies
template <class D, class Policies>
inline object make_getter(D* d, Policies const& policies, mpl::false_, int)
{
return python::make_function(
detail::datum<D>(d), policies, mpl::vector1<D&>()
);
}
// Handle non-member pointers without policies
template <class D>
inline object make_getter(D* d, not_specified, mpl::false_, long)
{
typedef typename default_datum_getter_policy<D>::type policies;
return detail::make_getter(d, policies(), mpl::false_(), 0);
}
// Handle pointers-to-members with policies
template <class C, class D, class Policies>
inline object make_getter(D C::*pm, Policies const& policies, mpl::true_, int)
{
#if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3003))
typedef typename remove_cv<C>::type Class;
#else
typedef C Class;
#endif
return python::make_function(
detail::member<D,Class>(pm)
, policies
, mpl::vector2<D&,Class&>()
);
}
// Handle pointers-to-members without policies
template <class C, class D>
inline object make_getter(D C::*pm, not_specified, mpl::true_, long)
{
typedef typename default_member_getter_policy<D>::type policies;
return detail::make_getter(pm, policies(), mpl::true_(), 0);
}
// Handle references
template <class D, class P>
inline object make_getter(D& d, P& p, mpl::false_, ...)
{
// Just dispatch to the handler for pointer types.
return detail::make_getter(&d, p, mpl::false_(), 0L);
}
//
// make_setter helper function family -- These helpers to
// boost::python::make_setter are used to dispatch behavior. The
// third argument is for compilers which don't support partial
// ordering at all and should always be passed 0.
//
// Handle non-member pointers
template <class D, class Policies>
inline object make_setter(D* p, Policies const& policies, mpl::false_, int)
{
return python::make_function(
detail::datum<D>(p), policies, mpl::vector2<void,D const&>()
);
}
// Handle pointers-to-members
template <class C, class D, class Policies>
inline object make_setter(D C::*pm, Policies const& policies, mpl::true_, int)
{
return python::make_function(
detail::member<D,C>(pm)
, policies
, mpl::vector3<void, C&, D const&>()
);
}
// Handle references
template <class D, class Policies>
inline object make_setter(D& x, Policies const& policies, mpl::false_, ...)
{
return detail::make_setter(&x, policies, mpl::false_(), 0L);
}
}
//
// make_getter function family -- build a callable object which
// retrieves data through the first argument and is appropriate for
// use as the `get' function in Python properties . The second,
// policies argument, is optional. We need both D& and D const&
// overloads in order be able to handle rvalues.
//
template <class D, class Policies>
inline object make_getter(D& d, Policies const& policies)
{
return detail::make_getter(d, policies, is_member_pointer<D>(), 0L);
}
template <class D, class Policies>
inline object make_getter(D const& d, Policies const& policies)
{
return detail::make_getter(d, policies, is_member_pointer<D>(), 0L);
}
template <class D>
inline object make_getter(D& x)
{
detail::not_specified policy
= detail::not_specified(); // suppress a SunPro warning
return detail::make_getter(x, policy, is_member_pointer<D>(), 0L);
}
# if !BOOST_WORKAROUND(__EDG_VERSION__, <= 238)
template <class D>
inline object make_getter(D const& d)
{
detail::not_specified policy
= detail::not_specified(); // Suppress a SunPro warning
return detail::make_getter(d, policy, is_member_pointer<D>(), 0L);
}
# endif
//
// make_setter function family -- build a callable object which
// writes data through the first argument and is appropriate for
// use as the `set' function in Python properties . The second,
// policies argument, is optional. We need both D& and D const&
// overloads in order be able to handle rvalues.
//
template <class D, class Policies>
inline object make_setter(D& x, Policies const& policies)
{
return detail::make_setter(x, policies, is_member_pointer<D>(), 0);
}
template <class D, class Policies>
inline object make_setter(D const& x, Policies const& policies)
{
return detail::make_setter(x, policies, is_member_pointer<D>(), 0);
}
template <class D>
inline object make_setter(D& x)
{
return detail::make_setter(x, default_call_policies(), is_member_pointer<D>(), 0);
}
# if !BOOST_WORKAROUND(__EDG_VERSION__, <= 238)
template <class D>
inline object make_setter(D const& x)
{
return detail::make_setter(x, default_call_policies(), is_member_pointer<D>(), 0);
}
# endif
}} // namespace boost::python
#endif // DATA_MEMBERS_DWA2002328_HPP