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Diffstat (limited to 'boost/hana/detail/struct_macros.hpp.erb')
-rw-r--r-- | boost/hana/detail/struct_macros.hpp.erb | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/boost/hana/detail/struct_macros.hpp.erb b/boost/hana/detail/struct_macros.hpp.erb new file mode 100644 index 0000000000..b3675e82af --- /dev/null +++ b/boost/hana/detail/struct_macros.hpp.erb @@ -0,0 +1,185 @@ +<%# + This is an ERB [1] template file used to generate the + <boost/hana/detail/struct_macros.hpp> header. The maximum + number of members that can be handled by the macros can + be controlled with the 'MAX_NUMBER_OF_MEMBERS' variable, + which can be set when calling ERB to generate the header: + + export MAX_NUMBER_OF_MEMBERS=55; erb struct_macros.hpp.erb + + 'MAX_NUMBER_OF_MEMBERS' must be <= 62, otherwise an error is triggered. + In case 'MAX_NUMBER_OF_MEMBERS' is not specified, it defaults to 40. + + [1]: http://en.wikipedia.org/wiki/ERuby +%> + +<% + MAX_NUMBER_OF_MEMBERS = (ENV["MAX_NUMBER_OF_MEMBERS"] || 40).to_i + raise "MAX_NUMBER_OF_MEMBERS must be <= 62" if MAX_NUMBER_OF_MEMBERS > 62 +%> + +/*! +@file +Defines the `BOOST_HANA_DEFINE_STRUCT`, `BOOST_HANA_ADAPT_STRUCT`, and +`BOOST_HANA_ADAPT_ADT` macros. + +@copyright Louis Dionne 2013-2017 +Distributed under the Boost Software License, Version 1.0. +(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) + */ + +////////////////////////////////////////////////////////////////////////////// +// THIS FILE IS GENERATED FROM THE <boost/hana/detail/struct_macros.erb.hpp> +// ERB TEMPLATE. DO NOT EDIT THIS FILE DIRECTLY. +// +// THE ERB TEMPLATE CONTAINS INFORMATION ABOUT HOW TO REGENERATE THIS FILE. +////////////////////////////////////////////////////////////////////////////// + +#ifndef BOOST_HANA_DETAIL_STRUCT_MACROS_HPP +#define BOOST_HANA_DETAIL_STRUCT_MACROS_HPP + +#include <boost/hana/config.hpp> +#include <boost/hana/detail/preprocessor.hpp> +#include <boost/hana/pair.hpp> +#include <boost/hana/string.hpp> +#include <boost/hana/tuple.hpp> + +#include <cstddef> +#include <utility> + + +BOOST_HANA_NAMESPACE_BEGIN namespace struct_detail { + template <typename Memptr, Memptr ptr> + struct member_ptr { + template <typename T> + constexpr decltype(auto) operator()(T&& t) const + { return static_cast<T&&>(t).*ptr; } + }; + + constexpr std::size_t strlen(char const* s) { + std::size_t n = 0; + while (*s++ != '\0') + ++n; + return n; + } + + template <std::size_t n, typename Names, std::size_t ...i> + constexpr auto prepare_member_name_impl(std::index_sequence<i...>) { + return hana::string_c<hana::at_c<n>(Names::get())[i]...>; + } + + template <std::size_t n, typename Names> + constexpr auto prepare_member_name() { + constexpr std::size_t len = strlen(hana::at_c<n>(Names::get())); + return prepare_member_name_impl<n, Names>(std::make_index_sequence<len>{}); + } +} BOOST_HANA_NAMESPACE_END + +////////////////////////////////////////////////////////////////////////////// +// BOOST_HANA_ADAPT_STRUCT +////////////////////////////////////////////////////////////////////////////// +template <typename ...> +struct BOOST_HANA_ADAPT_STRUCT_must_be_called_in_the_global_namespace; + +#define BOOST_HANA_ADAPT_STRUCT(...) \ + template <> \ + struct BOOST_HANA_ADAPT_STRUCT_must_be_called_in_the_global_namespace<>; \ + BOOST_HANA_ADAPT_STRUCT_IMPL(BOOST_HANA_PP_NARG(__VA_ARGS__), __VA_ARGS__)\ + static_assert(true, "force the usage of a trailing semicolon") \ +/**/ + +#define BOOST_HANA_ADAPT_STRUCT_IMPL(N, ...) \ + BOOST_HANA_PP_CONCAT(BOOST_HANA_ADAPT_STRUCT_IMPL_, N)(__VA_ARGS__) + +<% (0..MAX_NUMBER_OF_MEMBERS).each do |n| %> +#define BOOST_HANA_ADAPT_STRUCT_IMPL_<%= n+1 %>(TYPE <%= (1..n).map { |i| ", m#{i}" }.join %>) \ + namespace boost { namespace hana { \ + template <> \ + struct accessors_impl<TYPE> { \ + static constexpr auto apply() { \ + struct member_names { \ + static constexpr auto get() { \ + return ::boost::hana::make_tuple( \ + <%= (1..n).map { |i| "BOOST_HANA_PP_STRINGIZE(m#{i})" }.join(', ') %> \ + ); \ + } \ + }; \ + return ::boost::hana::make_tuple( \ + <%= (1..n).map { |i| "::boost::hana::make_pair(::boost::hana::struct_detail::prepare_member_name<#{i-1}, member_names>(), ::boost::hana::struct_detail::member_ptr<decltype(&TYPE::m#{i}), &TYPE::m#{i}>{})" }.join(', ') %>\ + ); \ + } \ + }; \ + }} \ +/**/ +<% end %> + +////////////////////////////////////////////////////////////////////////////// +// BOOST_HANA_ADAPT_ADT +////////////////////////////////////////////////////////////////////////////// +template <typename ...> +struct BOOST_HANA_ADAPT_ADT_must_be_called_in_the_global_namespace; + +#define BOOST_HANA_ADAPT_ADT(...) \ + template <> \ + struct BOOST_HANA_ADAPT_ADT_must_be_called_in_the_global_namespace<>; \ + BOOST_HANA_ADAPT_ADT_IMPL(BOOST_HANA_PP_NARG(__VA_ARGS__), __VA_ARGS__) \ + static_assert(true, "force the usage of a trailing semicolon") \ +/**/ + +#define BOOST_HANA_ADAPT_ADT_IMPL(N, ...) \ + BOOST_HANA_PP_CONCAT(BOOST_HANA_ADAPT_ADT_IMPL_, N)(__VA_ARGS__) + +<% (0..MAX_NUMBER_OF_MEMBERS).each do |n| %> +#define BOOST_HANA_ADAPT_ADT_IMPL_<%= n+1 %>(TYPE <%= (1..n).map { |i| ", m#{i}" }.join %>) \ + namespace boost { namespace hana { \ + template <> \ + struct accessors_impl<TYPE> { \ + template <typename ...> \ + static constexpr auto apply() { \ + struct member_names { \ + static constexpr auto get() { \ + return ::boost::hana::make_tuple( \ + <%= (1..n).map { |i| "BOOST_HANA_PP_STRINGIZE(BOOST_HANA_PP_FRONT m#{i})" }.join(', ') %>\ + ); \ + } \ + }; \ + return ::boost::hana::make_tuple( \ + <%= (1..n).map { |i| "::boost::hana::make_pair(::boost::hana::struct_detail::prepare_member_name<#{i-1}, member_names>(), BOOST_HANA_PP_DROP_FRONT m#{i})" }.join(', ') %>\ + ); \ + } \ + }; \ + }} \ +/**/ +<% end %> + +////////////////////////////////////////////////////////////////////////////// +// BOOST_HANA_DEFINE_STRUCT +////////////////////////////////////////////////////////////////////////////// +#define BOOST_HANA_DEFINE_STRUCT(...) \ + BOOST_HANA_DEFINE_STRUCT_IMPL(BOOST_HANA_PP_NARG(__VA_ARGS__), __VA_ARGS__) + +#define BOOST_HANA_DEFINE_STRUCT_IMPL(N, ...) \ + BOOST_HANA_PP_CONCAT(BOOST_HANA_DEFINE_STRUCT_IMPL_, N)(__VA_ARGS__) + +<% (0..MAX_NUMBER_OF_MEMBERS).each do |n| %> +#define BOOST_HANA_DEFINE_STRUCT_IMPL_<%= n+1 %>(TYPE <%= (1..n).map { |i| ", m#{i}" }.join %>) \ + <%= (1..n).map { |i| "BOOST_HANA_PP_DROP_BACK m#{i} BOOST_HANA_PP_BACK m#{i};" }.join(' ') %> \ + \ + struct hana_accessors_impl { \ + static constexpr auto apply() { \ + struct member_names { \ + static constexpr auto get() { \ + return ::boost::hana::make_tuple( \ + <%= (1..n).map { |i| "BOOST_HANA_PP_STRINGIZE(BOOST_HANA_PP_BACK m#{i})" }.join(', ') %>\ + ); \ + } \ + }; \ + return ::boost::hana::make_tuple( \ + <%= (1..n).map { |i| "::boost::hana::make_pair(::boost::hana::struct_detail::prepare_member_name<#{i-1}, member_names>(), ::boost::hana::struct_detail::member_ptr<decltype(&TYPE::BOOST_HANA_PP_BACK m#{i}), &TYPE::BOOST_HANA_PP_BACK m#{i}>{})" }.join(', ') %>\ + ); \ + } \ + } \ +/**/ +<% end %> + +#endif // !BOOST_HANA_DETAIL_STRUCT_MACROS_HPP |