forked from boostorg/mp11
41 lines
1.5 KiB
Plaintext
41 lines
1.5 KiB
Plaintext
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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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[section:function Helper Metafunctions, `<boost/mp11/function.hpp>`]
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[section `mp_and<T...>`]
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template<class... T> using mp_and = /*...*/;
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`mp_and<T...>` is an alias for the first type `U` in `T...` for which `mp_to_bool<U>` is `mp_false`.
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If no such type exists, the last one is returned. `mp_and<>` is `mp_true`. Similar to `std::conjunction` in C++17.
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[endsect]
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[section `mp_all<T...>`]
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template<class... T> using mp_all = /*...*/;
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`mp_all<T...>` is `mp_true` if `mp_to_bool<U>` is `mp_true` for all types `U` in `T...`, `mp_false` otherwise. Same as
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`mp_and`, but does not perform short-circuit evaluation. `mp_and<mp_false, void>` is `mp_false`, but `mp_all<mp_false, void>`
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is an error because `void` does not have a nested `value`. The upside is that `mp_all` is faster.
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[endsect]
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[section `mp_or<T...>`]
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template<class... T> using mp_or = /*...*/;
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`mp_or<T...>` is an alias for the first type `U` in `T...` for which `mp_to_bool<U>` is `mp_true`.
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If no such type exists, the last one is returned. `mp_or<>` is `mp_false`. Similar to `std::disjunction` in C++17.
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[endsect]
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[section `mp_any<T...>`]
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template<class... T> using mp_any = /*...*/;
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`mp_any<T...>` is `mp_true` if `mp_to_bool<U>` is `mp_true` for any type `U` in `T...`, `mp_false` otherwise. Same as
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`mp_or`, but does not perform short-circuit evaluation.
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[endsect]
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[endsect]
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