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

291 lines
8.6 KiB
C++

// Copyright David Abrahams 2001.
// 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 MAKE_CONSTRUCTOR_DWA20011221_HPP
# define MAKE_CONSTRUCTOR_DWA20011221_HPP
# include <boost/python/detail/prefix.hpp>
# include <boost/python/default_call_policies.hpp>
# include <boost/python/args.hpp>
# include <boost/python/object_fwd.hpp>
# include <boost/python/object/function_object.hpp>
# include <boost/python/object/make_holder.hpp>
# include <boost/python/object/pointer_holder.hpp>
# include <boost/python/converter/context_result_converter.hpp>
# include <boost/python/detail/caller.hpp>
# include <boost/python/detail/none.hpp>
# include <boost/mpl/size.hpp>
# include <boost/mpl/int.hpp>
# include <boost/mpl/push_front.hpp>
# include <boost/mpl/pop_front.hpp>
# include <boost/mpl/assert.hpp>
namespace boost { namespace python {
namespace detail
{
template <class T>
struct install_holder : converter::context_result_converter
{
install_holder(PyObject* args_)
: m_self(PyTuple_GetItem(args_, 0)) {}
PyObject* operator()(T x) const
{
dispatch(x, is_pointer<T>());
return none();
}
private:
template <class U>
void dispatch(U* x, mpl::true_) const
{
#if __cplusplus < 201103L
std::auto_ptr<U> owner(x);
dispatch(owner, mpl::false_());
#else
std::unique_ptr<U> owner(x);
dispatch(std::move(owner), mpl::false_());
#endif
}
template <class Ptr>
void dispatch(Ptr x, mpl::false_) const
{
typedef typename pointee<Ptr>::type value_type;
typedef objects::pointer_holder<Ptr,value_type> holder;
typedef objects::instance<holder> instance_t;
void* memory = holder::allocate(this->m_self, offsetof(instance_t, storage), sizeof(holder));
try {
#if __cplusplus < 201103L
(new (memory) holder(x))->install(this->m_self);
#else
(new (memory) holder(std::move(x)))->install(this->m_self);
#endif
}
catch(...) {
holder::deallocate(this->m_self, memory);
throw;
}
}
PyObject* m_self;
};
struct constructor_result_converter
{
template <class T>
struct apply
{
typedef install_holder<T> type;
};
};
template <class BaseArgs, class Offset>
struct offset_args
{
offset_args(BaseArgs base_) : base(base_) {}
BaseArgs base;
};
template <int N, class BaseArgs, class Offset>
inline PyObject* get(mpl::int_<N>, offset_args<BaseArgs,Offset> const& args_)
{
return get(mpl::int_<(N+Offset::value)>(), args_.base);
}
template <class BaseArgs, class Offset>
inline unsigned arity(offset_args<BaseArgs,Offset> const& args_)
{
return arity(args_.base) - Offset::value;
}
template <class BasePolicy_ = default_call_policies>
struct constructor_policy : BasePolicy_
{
constructor_policy(BasePolicy_ base) : BasePolicy_(base) {}
// If the BasePolicy_ supplied a result converter it would be
// ignored; issue an error if it's not the default.
BOOST_MPL_ASSERT_MSG(
(is_same<
typename BasePolicy_::result_converter
, default_result_converter
>::value)
, MAKE_CONSTRUCTOR_SUPPLIES_ITS_OWN_RESULT_CONVERTER_THAT_WOULD_OVERRIDE_YOURS
, (typename BasePolicy_::result_converter)
);
typedef constructor_result_converter result_converter;
typedef offset_args<typename BasePolicy_::argument_package, mpl::int_<1> > argument_package;
};
template <class InnerSignature>
struct outer_constructor_signature
{
typedef typename mpl::pop_front<InnerSignature>::type inner_args;
typedef typename mpl::push_front<inner_args,object>::type outer_args;
typedef typename mpl::push_front<outer_args,void>::type type;
};
// ETI workaround
template <>
struct outer_constructor_signature<int>
{
typedef int type;
};
//
// These helper functions for make_constructor (below) do the raw work
// of constructing a Python object from some invokable entity. See
// <boost/python/detail/caller.hpp> for more information about how
// the Sig arguments is used.
//
// @group make_constructor_aux {
template <class F, class CallPolicies, class Sig>
object make_constructor_aux(
F f // An object that can be invoked by detail::invoke()
, CallPolicies const& p // CallPolicies to use in the invocation
, Sig const& // An MPL sequence of argument types expected by F
)
{
typedef typename outer_constructor_signature<Sig>::type outer_signature;
typedef constructor_policy<CallPolicies> inner_policy;
return objects::function_object(
objects::py_function(
detail::caller<F,inner_policy,Sig>(f, inner_policy(p))
, outer_signature()
)
);
}
// As above, except that it accepts argument keywords. NumKeywords
// is used only for a compile-time assertion to make sure the user
// doesn't pass more keywords than the function can accept. To
// disable all checking, pass mpl::int_<0> for NumKeywords.
template <class F, class CallPolicies, class Sig, class NumKeywords>
object make_constructor_aux(
F f
, CallPolicies const& p
, Sig const&
, detail::keyword_range const& kw // a [begin,end) pair of iterators over keyword names
, NumKeywords // An MPL integral type wrapper: the size of kw
)
{
enum { arity = mpl::size<Sig>::value - 1 };
typedef typename detail::error::more_keywords_than_function_arguments<
NumKeywords::value, arity
>::too_many_keywords assertion BOOST_ATTRIBUTE_UNUSED;
typedef typename outer_constructor_signature<Sig>::type outer_signature;
typedef constructor_policy<CallPolicies> inner_policy;
return objects::function_object(
objects::py_function(
detail::caller<F,inner_policy,Sig>(f, inner_policy(p))
, outer_signature()
)
, kw
);
}
// }
//
// These dispatch functions are used to discriminate between the
// cases when the 3rd argument is keywords or when it is a
// signature.
//
// @group Helpers for make_constructor when called with 3 arguments. {
//
template <class F, class CallPolicies, class Keywords>
object make_constructor_dispatch(F f, CallPolicies const& policies, Keywords const& kw, mpl::true_)
{
return detail::make_constructor_aux(
f
, policies
, detail::get_signature(f)
, kw.range()
, mpl::int_<Keywords::size>()
);
}
template <class F, class CallPolicies, class Signature>
object make_constructor_dispatch(F f, CallPolicies const& policies, Signature const& sig, mpl::false_)
{
return detail::make_constructor_aux(
f
, policies
, sig
);
}
// }
}
// These overloaded functions wrap a function or member function
// pointer as a Python object, using optional CallPolicies,
// Keywords, and/or Signature. @group {
//
template <class F>
object make_constructor(F f)
{
return detail::make_constructor_aux(
f,default_call_policies(), detail::get_signature(f));
}
template <class F, class CallPolicies>
object make_constructor(F f, CallPolicies const& policies)
{
return detail::make_constructor_aux(
f, policies, detail::get_signature(f));
}
template <class F, class CallPolicies, class KeywordsOrSignature>
object make_constructor(
F f
, CallPolicies const& policies
, KeywordsOrSignature const& keywords_or_signature)
{
typedef typename
detail::is_reference_to_keywords<KeywordsOrSignature&>::type
is_kw;
return detail::make_constructor_dispatch(
f
, policies
, keywords_or_signature
, is_kw()
);
}
template <class F, class CallPolicies, class Keywords, class Signature>
object make_constructor(
F f
, CallPolicies const& policies
, Keywords const& kw
, Signature const& sig
)
{
return detail::make_constructor_aux(
f
, policies
, sig
, kw.range()
, mpl::int_<Keywords::size>()
);
}
// }
}}
#endif // MAKE_CONSTRUCTOR_DWA20011221_HPP