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Diffstat (limited to 'boost/hof/detail/callable_base.hpp')
-rw-r--r-- | boost/hof/detail/callable_base.hpp | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/boost/hof/detail/callable_base.hpp b/boost/hof/detail/callable_base.hpp new file mode 100644 index 0000000000..b214043e0b --- /dev/null +++ b/boost/hof/detail/callable_base.hpp @@ -0,0 +1,65 @@ +/*============================================================================= + Copyright (c) 2015 Paul Fultz II + callable_base.h + 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 BOOST_HOF_GUARD_CALLABLE_BASE_H +#define BOOST_HOF_GUARD_CALLABLE_BASE_H + +#include <boost/hof/detail/delegate.hpp> +#include <boost/hof/detail/result_of.hpp> +#include <boost/hof/apply.hpp> + +#ifndef BOOST_HOF_CALLABLE_BASE_USE_TEMPLATE_ALIAS +#if (defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ < 7) +#define BOOST_HOF_CALLABLE_BASE_USE_TEMPLATE_ALIAS 0 +#else +#define BOOST_HOF_CALLABLE_BASE_USE_TEMPLATE_ALIAS 1 +#endif +#endif + +namespace boost { namespace hof { namespace detail { + +template<class F> +struct non_class_function +{ + F f; + BOOST_HOF_DELEGATE_CONSTRUCTOR(non_class_function, F, f) + + template<class... Ts> + constexpr BOOST_HOF_SFINAE_RESULT(apply_f, id_<F>, id_<Ts>...) + operator()(Ts&&... xs) const BOOST_HOF_SFINAE_RETURNS + ( + boost::hof::apply(f, BOOST_HOF_FORWARD(Ts)(xs)...) + ); +}; + +template<class F> +struct callable_base_type +: std::conditional<(BOOST_HOF_IS_CLASS(F) && !BOOST_HOF_IS_FINAL(F) && !BOOST_HOF_IS_POLYMORPHIC(F)), F, non_class_function<F>> +{}; + +#if BOOST_HOF_CALLABLE_BASE_USE_TEMPLATE_ALIAS +template<class F> +using callable_base = typename callable_base_type<F>::type; +#else +template<class F> +struct callable_base +: callable_base_type<F>::type +{ + typedef typename callable_base_type<F>::type base; + BOOST_HOF_INHERIT_CONSTRUCTOR(callable_base, base) +}; + +template<class F> +struct callable_base_type<callable_base<F>> +: callable_base_type<F> +{}; + +#endif + +}}} // namespace boost::hof + +#endif |