36 lines
1.7 KiB
Plaintext
36 lines
1.7 KiB
Plaintext
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////
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Copyright 2017 Peter Dimov
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Distributed under the Boost Software License, Version 1.0.
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See 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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[#overview]
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# Overview
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Mp11 is a C++11 metaprogramming library for compile-time manipulation of data structures
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that contain types. It's based on template aliases and variadic templates and implements the
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approach outlined in the article
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<<simple_cxx11_metaprogramming.adoc#,"Simple {cpp} metaprogramming">>
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and <<simple_cxx11_metaprogramming_2.adoc#,its sequel>>. Reading these
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articles before proceeding with this documentation is _highly_ recommended.
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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::add_pointer_t, std::tuple<int, float>>`
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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<mp_list, std::tuple<int, float>>;
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and get `std::tuple<mp_list<int>, mp_list<float>>`.
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