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Diffstat (limited to 'boost/callable_traits/args.hpp')
-rw-r--r-- | boost/callable_traits/args.hpp | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/boost/callable_traits/args.hpp b/boost/callable_traits/args.hpp new file mode 100644 index 0000000000..6dcaaccc12 --- /dev/null +++ b/boost/callable_traits/args.hpp @@ -0,0 +1,97 @@ +/* + +@Copyright Barrett Adair 2015-2017 +Distributed under the Boost Software License, Version 1.0. +(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) + +*/ + +#ifndef BOOST_CLBL_TRTS_ARGS_HPP +#define BOOST_CLBL_TRTS_ARGS_HPP + +#include <boost/callable_traits/detail/core.hpp> + +namespace boost { namespace callable_traits { + +//[ args_hpp +/*`[section:ref_args args] +[heading Header] +``#include <boost/callable_traits/args.hpp>`` +[heading Definition] +*/ + +template<typename T, template<class...> class Container = std::tuple> +using args_t = //see below +//<- + detail::try_but_fail_if_invalid< + typename detail::traits< + detail::shallow_decay<T>>::template expand_args<Container>, + cannot_expand_the_parameter_list_of_first_template_argument>; + +namespace detail { + + template<typename T, template<class...> class Container, + typename = std::false_type> + struct args_impl {}; + + template<typename T, template<class...> class Container> + struct args_impl <T, Container, typename std::is_same< + args_t<T, Container>, detail::dummy>::type> + { + using type = args_t<T, Container>; + }; +} + +//-> + +template<typename T, + template<class...> class Container = std::tuple> +struct args : detail::args_impl<T, Container> {}; + +//<- +}} // namespace boost::callable_traits +//-> + +/*` +[heading Constraints] +* `T` must be one of the following: + * function + * function pointer + * function reference + * member function pointer + * member data pointer + * user-defined type with a non-overloaded `operator()` + * type of a non-generic lambda + +[heading Behavior] +* When the constraints are violated, a substitution failure occurs. +* When `T` is a function, function pointer, or function reference, the aliased type is `Container` instantiated with the function's parameter types. +* When `T` is a function object, the aliased type is `Container` instantiated with the `T::operator()` parameter types. +* When `T` is a member function pointer, the aliased type is a `Container` instantiation, where the first type argument is a reference to the parent class of `T`, qualified according to the member qualifiers on `T`, such that the first type is equivalent to `boost::callable_traits::qualified_class_of_t<T>`. The subsequent type arguments, if any, are the parameter types of the member function. +* When `T` is a member data pointer, the aliased type is `Container` with a single element, which is a `const` reference to the parent class of `T`. + +[heading Input/Output Examples] +[table + [[`T`] [`args_t<T>`]] + [[`void(float, char, int)`] [`std::tuple<float, char, int>`]] + [[`void(*)(float, char, int)`] [`std::tuple<float, char, int`]] + [[`void(&)(float, char, int)`] [`std::tuple<float, char, int`]] + [[`void(float, char, int) const &&`][`std::tuple<float, char, int>`]] + [[`void(*)()`] [`std::tuple<>`]] + [[`void(foo::* const &)(float, char, int)`] [`std::tuple<foo&, float, char, int>`]] + [[`int(foo::*)(int) const`] [`std::tuple<const foo&, int>`]] + [[`void(foo::*)() volatile &&`] [`std::tuple<volatile foo &&>`]] + [[`int foo::*`] [`std::tuple<const foo&>`]] + [[`const int foo::*`] [`std::tuple<const foo&>`]] + [[`int`] [(substitution failure)]] + [[`int (*const)()`] [(substitution failure)]] +] + +[heading Example Program] +[import ../example/args.cpp] +[args] +[endsect] +*/ +//] + +#endif // #ifndef BOOST_CLBL_TRTS_ARGS_HPP |