1 /*! 2 @file 3 Forward declares `boost::hana::basic_tuple`. 4 5 @copyright Louis Dionne 2013-2017 6 Distributed under the Boost Software License, Version 1.0. 7 (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) 8 */ 9 10 #ifndef BOOST_HANA_FWD_BASIC_TUPLE_HPP 11 #define BOOST_HANA_FWD_BASIC_TUPLE_HPP 12 13 #include <boost/hana/config.hpp> 14 #include <boost/hana/fwd/core/make.hpp> 15 16 17 BOOST_HANA_NAMESPACE_BEGIN 18 //! @ingroup group-datatypes 19 //! Stripped down version of `hana::tuple`. 20 //! 21 //! Whereas `hana::tuple` aims to provide an interface somewhat close to a 22 //! `std::tuple`, `basic_tuple` provides the strict minimum required to 23 //! implement a closure with maximum compile-time efficiency. 24 //! 25 //! @note 26 //! When you use a container, remember not to make assumptions about its 27 //! representation, unless the documentation gives you those guarantees. 28 //! More details [in the tutorial](@ref tutorial-containers-types). 29 //! 30 //! 31 //! Modeled concepts 32 //! ---------------- 33 //! `Sequence`, and all the concepts it refines 34 template <typename ...Xs> 35 struct basic_tuple; 36 37 //! Tag representing `hana::basic_tuple`. 38 //! @relates hana::basic_tuple 39 struct basic_tuple_tag { }; 40 41 #ifdef BOOST_HANA_DOXYGEN_INVOKED 42 //! Function object for creating a `basic_tuple`. 43 //! @relates hana::basic_tuple 44 //! 45 //! Given zero or more objects `xs...`, `make<basic_tuple_tag>` returns a 46 //! new `basic_tuple` containing those objects. The elements are held by 47 //! value inside the resulting tuple, and they are hence copied or moved 48 //! in. This is analogous to `std::make_tuple` for creating `basic_tuple`s. 49 //! 50 //! 51 //! Example 52 //! ------- 53 //! @include example/basic_tuple/make.cpp 54 template <> __anon55475f2b0102(auto&& ...xs) 55 constexpr auto make<basic_tuple_tag> = [](auto&& ...xs) { 56 return basic_tuple<std::decay_t<decltype(xs)>...>{forwarded(xs)...}; 57 }; 58 #endif 59 60 //! Alias to `make<basic_tuple_tag>`; provided for convenience. 61 //! @relates hana::basic_tuple 62 //! 63 //! 64 //! Example 65 //! ------- 66 //! @include example/basic_tuple/make.cpp 67 constexpr auto make_basic_tuple = make<basic_tuple_tag>; 68 BOOST_HANA_NAMESPACE_END 69 70 #endif // !BOOST_HANA_FWD_BASIC_TUPLE_HPP 71