forked from boostorg/mp11
30 lines
1.5 KiB
Plaintext
30 lines
1.5 KiB
Plaintext
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[/
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/ Copyright 2017 Peter Dimov
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/
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/ Distributed under the Boost Software License, Version 1.0. (See
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/ accompanying file LICENSE_1_0.txt or copy at
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/ http://www.boost.org/LICENSE_1_0.txt)
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/]
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Mp11 is a C++11 metaprogramming library based on template aliases and variadic templates.
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It implements the approach outlined in the article
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[@http://pdimov.com/cpp2/simple_cxx11_metaprogramming.html Simple C++11 metaprogramming]
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([@http://pdimov.com/cpp2/simple_cxx11_metaprogramming_2.html part 2]).
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The general principles upon which Mp11 is built are that algorithms and metafunctions are
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template aliases of the form `F<T...>` and data structures are lists of the form `L<T...>`,
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with the library placing no requirements on `L`. `mp_list<T...>` is the built-in list type,
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but `std::tuple<T...>`, `std::pair<T1, T2>` and `std::variant<T...>` are also perfectly
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legitimate list types, although of course `std:pair<T1, T2>`, due to having exactly two elements,
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is not resizeable and will consequently not work with algorithms that need to add or remove
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elements.
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Another distinguishing feature of this approach is that lists (`L<T...>`) have the same form as
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metafunctions (`F<T...>`) and can therefore be used as such. For example, applying `std::add_pointer_t`
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to the list `std::tuple<int, float>` by way of `mp_transform<std::tuple<int, float>, std::add_pointer_t>`
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gives us `std::tuple<int*, float*>`, but we can also apply `mp_list` to the same tuple:
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using R = mp_transform<std::tuple<int, float>, mp_list>;
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and get `std::tuple<mp_list<int>, mp_list<float>>`.
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