211 lines
6.7 KiB
C++
211 lines
6.7 KiB
C++
// Boost result_of library
|
|
|
|
// Copyright Douglas Gregor 2004. Use, modification and
|
|
// distribution is subject to 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)
|
|
|
|
// For more information, see http://www.boost.org/libs/utility
|
|
#ifndef BOOST_RESULT_OF_HPP
|
|
#define BOOST_RESULT_OF_HPP
|
|
|
|
#include <boost/config.hpp>
|
|
#include <boost/preprocessor/cat.hpp>
|
|
#include <boost/preprocessor/iteration/iterate.hpp>
|
|
#include <boost/preprocessor/repetition/enum_params.hpp>
|
|
#include <boost/preprocessor/repetition/enum_trailing_params.hpp>
|
|
#include <boost/preprocessor/repetition/enum_binary_params.hpp>
|
|
#include <boost/preprocessor/repetition/enum_shifted_params.hpp>
|
|
#include <boost/preprocessor/facilities/intercept.hpp>
|
|
#include <boost/detail/workaround.hpp>
|
|
#include <boost/mpl/has_xxx.hpp>
|
|
#include <boost/mpl/if.hpp>
|
|
#include <boost/mpl/eval_if.hpp>
|
|
#include <boost/mpl/bool.hpp>
|
|
#include <boost/mpl/identity.hpp>
|
|
#include <boost/mpl/or.hpp>
|
|
#include <boost/type_traits/is_class.hpp>
|
|
#include <boost/type_traits/is_pointer.hpp>
|
|
#include <boost/type_traits/is_member_function_pointer.hpp>
|
|
#include <boost/type_traits/remove_cv.hpp>
|
|
#include <boost/type_traits/remove_reference.hpp>
|
|
#include <boost/utility/declval.hpp>
|
|
#include <boost/utility/enable_if.hpp>
|
|
|
|
#ifndef BOOST_RESULT_OF_NUM_ARGS
|
|
# define BOOST_RESULT_OF_NUM_ARGS 16
|
|
#endif
|
|
|
|
// Use the decltype-based version of result_of by default if the compiler
|
|
// supports N3276 <http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2011/n3276.pdf>.
|
|
// The user can force the choice by defining BOOST_RESULT_OF_USE_DECLTYPE,
|
|
// BOOST_RESULT_OF_USE_TR1, or BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK but not more than one!
|
|
#if (defined(BOOST_RESULT_OF_USE_DECLTYPE) && defined(BOOST_RESULT_OF_USE_TR1)) || \
|
|
(defined(BOOST_RESULT_OF_USE_DECLTYPE) && defined(BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK)) || \
|
|
(defined(BOOST_RESULT_OF_USE_TR1) && defined(BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK))
|
|
# error More than one of BOOST_RESULT_OF_USE_DECLTYPE, BOOST_RESULT_OF_USE_TR1 and \
|
|
BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK cannot be defined at the same time.
|
|
#endif
|
|
|
|
#if defined(BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK) && defined(BOOST_MPL_CFG_NO_HAS_XXX_TEMPLATE)
|
|
# error Cannot fallback to decltype if BOOST_MPL_CFG_NO_HAS_XXX_TEMPLATE is not defined.
|
|
#endif
|
|
|
|
#ifndef BOOST_RESULT_OF_USE_TR1
|
|
# ifndef BOOST_RESULT_OF_USE_DECLTYPE
|
|
# ifndef BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK
|
|
# ifndef BOOST_NO_CXX11_DECLTYPE_N3276 // this implies !defined(BOOST_NO_CXX11_DECLTYPE)
|
|
# define BOOST_RESULT_OF_USE_DECLTYPE
|
|
# else
|
|
# define BOOST_RESULT_OF_USE_TR1
|
|
# endif
|
|
# endif
|
|
# endif
|
|
#endif
|
|
|
|
namespace boost {
|
|
|
|
template<typename F> struct result_of;
|
|
template<typename F> struct tr1_result_of; // a TR1-style implementation of result_of
|
|
|
|
#if !defined(BOOST_NO_SFINAE)
|
|
namespace detail {
|
|
|
|
BOOST_MPL_HAS_XXX_TRAIT_DEF(result_type)
|
|
|
|
// Work around a nvcc bug by only defining has_result when it's needed.
|
|
#ifdef BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK
|
|
BOOST_MPL_HAS_XXX_TEMPLATE_DEF(result)
|
|
#endif
|
|
|
|
template<typename F, typename FArgs, bool HasResultType> struct tr1_result_of_impl;
|
|
|
|
template<typename F> struct cpp0x_result_of;
|
|
|
|
#ifdef BOOST_NO_SFINAE_EXPR
|
|
|
|
// There doesn't seem to be any other way to turn this off such that the presence of
|
|
// the user-defined operator,() below doesn't cause spurious warning all over the place,
|
|
// so unconditionally turn it off.
|
|
#if BOOST_MSVC
|
|
# pragma warning(disable: 4913) // user defined binary operator ',' exists but no overload could convert all operands, default built-in binary operator ',' used
|
|
#endif
|
|
|
|
struct result_of_private_type {};
|
|
|
|
struct result_of_weird_type {
|
|
friend result_of_private_type operator,(result_of_private_type, result_of_weird_type);
|
|
};
|
|
|
|
typedef char result_of_yes_type; // sizeof(result_of_yes_type) == 1
|
|
typedef char (&result_of_no_type)[2]; // sizeof(result_of_no_type) == 2
|
|
|
|
template<typename T>
|
|
result_of_no_type result_of_is_private_type(T const &);
|
|
result_of_yes_type result_of_is_private_type(result_of_private_type);
|
|
|
|
template<typename C>
|
|
struct result_of_callable_class : C {
|
|
result_of_callable_class();
|
|
typedef result_of_private_type const &(*pfn_t)(...);
|
|
operator pfn_t() const volatile;
|
|
};
|
|
|
|
template<typename C>
|
|
struct result_of_wrap_callable_class {
|
|
typedef result_of_callable_class<C> type;
|
|
};
|
|
|
|
template<typename C>
|
|
struct result_of_wrap_callable_class<C const> {
|
|
typedef result_of_callable_class<C> const type;
|
|
};
|
|
|
|
template<typename C>
|
|
struct result_of_wrap_callable_class<C volatile> {
|
|
typedef result_of_callable_class<C> volatile type;
|
|
};
|
|
|
|
template<typename C>
|
|
struct result_of_wrap_callable_class<C const volatile> {
|
|
typedef result_of_callable_class<C> const volatile type;
|
|
};
|
|
|
|
template<typename C>
|
|
struct result_of_wrap_callable_class<C &> {
|
|
typedef typename result_of_wrap_callable_class<C>::type &type;
|
|
};
|
|
|
|
template<typename F, bool TestCallability = true> struct cpp0x_result_of_impl;
|
|
|
|
#else // BOOST_NO_SFINAE_EXPR
|
|
|
|
template<typename T>
|
|
struct result_of_always_void
|
|
{
|
|
typedef void type;
|
|
};
|
|
|
|
template<typename F, typename Enable = void> struct cpp0x_result_of_impl {};
|
|
|
|
#endif // BOOST_NO_SFINAE_EXPR
|
|
|
|
template<typename F>
|
|
struct result_of_void_impl
|
|
{
|
|
typedef void type;
|
|
};
|
|
|
|
template<typename R>
|
|
struct result_of_void_impl<R (*)(void)>
|
|
{
|
|
typedef R type;
|
|
};
|
|
|
|
template<typename R>
|
|
struct result_of_void_impl<R (&)(void)>
|
|
{
|
|
typedef R type;
|
|
};
|
|
|
|
// Determine the return type of a function pointer or pointer to member.
|
|
template<typename F, typename FArgs>
|
|
struct result_of_pointer
|
|
: tr1_result_of_impl<typename remove_cv<F>::type, FArgs, false> { };
|
|
|
|
template<typename F, typename FArgs>
|
|
struct tr1_result_of_impl<F, FArgs, true>
|
|
{
|
|
typedef typename F::result_type type;
|
|
};
|
|
|
|
template<typename FArgs>
|
|
struct is_function_with_no_args : mpl::false_ {};
|
|
|
|
template<typename F>
|
|
struct is_function_with_no_args<F(void)> : mpl::true_ {};
|
|
|
|
template<typename F, typename FArgs>
|
|
struct result_of_nested_result : F::template result<FArgs>
|
|
{};
|
|
|
|
template<typename F, typename FArgs>
|
|
struct tr1_result_of_impl<F, FArgs, false>
|
|
: mpl::if_<is_function_with_no_args<FArgs>,
|
|
result_of_void_impl<F>,
|
|
result_of_nested_result<F, FArgs> >::type
|
|
{};
|
|
|
|
} // end namespace detail
|
|
|
|
#define BOOST_PP_ITERATION_PARAMS_1 (3,(0,BOOST_RESULT_OF_NUM_ARGS,<boost/utility/detail/result_of_iterate.hpp>))
|
|
#include BOOST_PP_ITERATE()
|
|
|
|
#else
|
|
# define BOOST_NO_RESULT_OF 1
|
|
#endif
|
|
|
|
}
|
|
|
|
#endif // BOOST_RESULT_OF_HPP
|