264 lines
		
	
	
		
			7.2 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
		
		
			
		
	
	
			264 lines
		
	
	
		
			7.2 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
|   | #ifndef BOOST_MP11_UTILITY_HPP_INCLUDED
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|  | #define BOOST_MP11_UTILITY_HPP_INCLUDED
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|  | 
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|  | // Copyright 2015-2020 Peter Dimov.
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|  | //
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|  | // Distributed under the Boost Software License, Version 1.0.
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|  | //
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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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|  | #include <boost/mp11/integral.hpp>
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|  | #include <boost/mp11/detail/mp_list.hpp>
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|  | #include <boost/mp11/detail/mp_fold.hpp>
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|  | #include <boost/mp11/detail/mp_front.hpp>
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|  | #include <boost/mp11/detail/mp_rename.hpp>
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|  | #include <boost/mp11/detail/config.hpp>
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|  | 
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|  | namespace boost | ||
|  | { | ||
|  | namespace mp11 | ||
|  | { | ||
|  | 
 | ||
|  | // mp_identity
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|  | template<class T> struct mp_identity | ||
|  | { | ||
|  |     using type = T; | ||
|  | }; | ||
|  | 
 | ||
|  | // mp_identity_t
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|  | template<class T> using mp_identity_t = typename mp_identity<T>::type; | ||
|  | 
 | ||
|  | // mp_inherit
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|  | template<class... T> struct mp_inherit: T... {}; | ||
|  | 
 | ||
|  | // mp_if, mp_if_c
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|  | namespace detail | ||
|  | { | ||
|  | 
 | ||
|  | template<bool C, class T, class... E> struct mp_if_c_impl | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template<class T, class... E> struct mp_if_c_impl<true, T, E...> | ||
|  | { | ||
|  |     using type = T; | ||
|  | }; | ||
|  | 
 | ||
|  | template<class T, class E> struct mp_if_c_impl<false, T, E> | ||
|  | { | ||
|  |     using type = E; | ||
|  | }; | ||
|  | 
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|  | } // namespace detail
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|  | 
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|  | template<bool C, class T, class... E> using mp_if_c = typename detail::mp_if_c_impl<C, T, E...>::type; | ||
|  | template<class C, class T, class... E> using mp_if = typename detail::mp_if_c_impl<static_cast<bool>(C::value), T, E...>::type; | ||
|  | 
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|  | // mp_valid
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|  | 
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|  | #if BOOST_MP11_WORKAROUND( BOOST_MP11_INTEL, != 0 ) // tested at 1800
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|  | 
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|  | // contributed by Roland Schulz in https://github.com/boostorg/mp11/issues/17
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|  | 
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|  | namespace detail | ||
|  | { | ||
|  | 
 | ||
|  | template<class...> using void_t = void; | ||
|  | 
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|  | template<class, template<class...> class F, class... T> | ||
|  | struct mp_valid_impl: mp_false {}; | ||
|  | 
 | ||
|  | template<template<class...> class F, class... T> | ||
|  | struct mp_valid_impl<void_t<F<T...>>, F, T...>: mp_true {}; | ||
|  | 
 | ||
|  | } // namespace detail
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|  | 
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|  | template<template<class...> class F, class... T> using mp_valid = typename detail::mp_valid_impl<void, F, T...>; | ||
|  | 
 | ||
|  | #else
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|  | 
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|  | // implementation by Bruno Dutra (by the name is_evaluable)
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|  | namespace detail | ||
|  | { | ||
|  | 
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|  | template<template<class...> class F, class... T> struct mp_valid_impl | ||
|  | { | ||
|  |     template<template<class...> class G, class = G<T...>> static mp_true check(int); | ||
|  |     template<template<class...> class> static mp_false check(...); | ||
|  | 
 | ||
|  |     using type = decltype(check<F>(0)); | ||
|  | }; | ||
|  | 
 | ||
|  | } // namespace detail
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|  | 
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|  | template<template<class...> class F, class... T> using mp_valid = typename detail::mp_valid_impl<F, T...>::type; | ||
|  | 
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|  | #endif
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|  | 
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|  | template<class Q, class... T> using mp_valid_q = mp_valid<Q::template fn, T...>; | ||
|  | 
 | ||
|  | // mp_defer
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|  | namespace detail | ||
|  | { | ||
|  | 
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|  | template<template<class...> class F, class... T> struct mp_defer_impl | ||
|  | { | ||
|  |     using type = F<T...>; | ||
|  | }; | ||
|  | 
 | ||
|  | struct mp_no_type | ||
|  | { | ||
|  | }; | ||
|  | 
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|  | #if BOOST_MP11_WORKAROUND( BOOST_MP11_CUDA, >= 9000000 && BOOST_MP11_CUDA < 10000000 )
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|  | 
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|  | template<template<class...> class F, class... T> struct mp_defer_cuda_workaround | ||
|  | { | ||
|  |     using type = mp_if<mp_valid<F, T...>, detail::mp_defer_impl<F, T...>, detail::mp_no_type>; | ||
|  | }; | ||
|  | 
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|  | #endif
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|  | 
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|  | } // namespace detail
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|  | 
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|  | #if BOOST_MP11_WORKAROUND( BOOST_MP11_CUDA, >= 9000000 && BOOST_MP11_CUDA < 10000000 )
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|  | 
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|  | template<template<class...> class F, class... T> using mp_defer = typename detail::mp_defer_cuda_workaround< F, T...>::type; | ||
|  | 
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|  | #else
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|  | 
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|  | template<template<class...> class F, class... T> using mp_defer = mp_if<mp_valid<F, T...>, detail::mp_defer_impl<F, T...>, detail::mp_no_type>; | ||
|  | 
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|  | #endif
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|  | 
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|  | // mp_eval_if, mp_eval_if_c
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|  | namespace detail | ||
|  | { | ||
|  | 
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|  | template<bool C, class T, template<class...> class F, class... U> struct mp_eval_if_c_impl; | ||
|  | 
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|  | template<class T, template<class...> class F, class... U> struct mp_eval_if_c_impl<true, T, F, U...> | ||
|  | { | ||
|  |     using type = T; | ||
|  | }; | ||
|  | 
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|  | template<class T, template<class...> class F, class... U> struct mp_eval_if_c_impl<false, T, F, U...>: mp_defer<F, U...> | ||
|  | { | ||
|  | }; | ||
|  | 
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|  | } // namespace detail
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|  | 
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|  | template<bool C, class T, template<class...> class F, class... U> using mp_eval_if_c = typename detail::mp_eval_if_c_impl<C, T, F, U...>::type; | ||
|  | template<class C, class T, template<class...> class F, class... U> using mp_eval_if = typename detail::mp_eval_if_c_impl<static_cast<bool>(C::value), T, F, U...>::type; | ||
|  | template<class C, class T, class Q, class... U> using mp_eval_if_q = typename detail::mp_eval_if_c_impl<static_cast<bool>(C::value), T, Q::template fn, U...>::type; | ||
|  | 
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|  | // mp_eval_if_not
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|  | template<class C, class T, template<class...> class F, class... U> using mp_eval_if_not = mp_eval_if<mp_not<C>, T, F, U...>; | ||
|  | template<class C, class T, class Q, class... U> using mp_eval_if_not_q = mp_eval_if<mp_not<C>, T, Q::template fn, U...>; | ||
|  | 
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|  | // mp_eval_or
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|  | template<class T, template<class...> class F, class... U> using mp_eval_or = mp_eval_if_not<mp_valid<F, U...>, T, F, U...>; | ||
|  | template<class T, class Q, class... U> using mp_eval_or_q = mp_eval_or<T, Q::template fn, U...>; | ||
|  | 
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|  | // mp_valid_and_true
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|  | template<template<class...> class F, class... T> using mp_valid_and_true = mp_eval_or<mp_false, F, T...>; | ||
|  | template<class Q, class... T> using mp_valid_and_true_q = mp_valid_and_true<Q::template fn, T...>; | ||
|  | 
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|  | // mp_cond
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|  | 
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|  | // so elegant; so doesn't work
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|  | // template<class C, class T, class... E> using mp_cond = mp_eval_if<C, T, mp_cond, E...>;
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|  | 
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|  | namespace detail | ||
|  | { | ||
|  | 
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|  | template<class C, class T, class... E> struct mp_cond_impl; | ||
|  | 
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|  | } // namespace detail
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|  | 
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|  | template<class C, class T, class... E> using mp_cond = typename detail::mp_cond_impl<C, T, E...>::type; | ||
|  | 
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|  | namespace detail | ||
|  | { | ||
|  | 
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|  | template<class C, class T, class... E> using mp_cond_ = mp_eval_if<C, T, mp_cond, E...>; | ||
|  | 
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|  | template<class C, class T, class... E> struct mp_cond_impl: mp_defer<mp_cond_, C, T, E...> | ||
|  | { | ||
|  | }; | ||
|  | 
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|  | } // namespace detail
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|  | 
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|  | // mp_quote
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|  | template<template<class...> class F> struct mp_quote | ||
|  | { | ||
|  |     // the indirection through mp_defer works around the language inability
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|  |     // to expand T... into a fixed parameter list of an alias template
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|  | 
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|  |     template<class... T> using fn = typename mp_defer<F, T...>::type; | ||
|  | }; | ||
|  | 
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|  | // mp_quote_trait
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|  | template<template<class...> class F> struct mp_quote_trait | ||
|  | { | ||
|  |     template<class... T> using fn = typename F<T...>::type; | ||
|  | }; | ||
|  | 
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|  | // mp_invoke_q
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|  | #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1900 )
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|  | 
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|  | namespace detail | ||
|  | { | ||
|  | 
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|  | template<class Q, class... T> struct mp_invoke_q_impl: mp_defer<Q::template fn, T...> {}; | ||
|  | 
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|  | } // namespace detail
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|  | 
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|  | template<class Q, class... T> using mp_invoke_q = typename detail::mp_invoke_q_impl<Q, T...>::type; | ||
|  | 
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|  | #elif BOOST_MP11_WORKAROUND( BOOST_MP11_GCC, < 50000 )
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|  | 
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|  | template<class Q, class... T> using mp_invoke_q = typename mp_defer<Q::template fn, T...>::type; | ||
|  | 
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|  | #else
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|  | 
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|  | template<class Q, class... T> using mp_invoke_q = typename Q::template fn<T...>; | ||
|  | 
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|  | #endif
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|  | 
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|  | // mp_not_fn<P>
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|  | template<template<class...> class P> struct mp_not_fn | ||
|  | { | ||
|  |     template<class... T> using fn = mp_not< mp_invoke_q<mp_quote<P>, T...> >; | ||
|  | }; | ||
|  | 
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|  | template<class Q> using mp_not_fn_q = mp_not_fn<Q::template fn>; | ||
|  | 
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|  | // mp_compose
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|  | namespace detail | ||
|  | { | ||
|  | 
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|  | template<class L, class Q> using mp_compose_helper = mp_list< mp_apply_q<Q, L> >; | ||
|  | 
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|  | } // namespace detail
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|  | 
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|  | #if !BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1900 )
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|  | 
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|  | template<template<class...> class... F> struct mp_compose | ||
|  | { | ||
|  |     template<class... T> using fn = mp_front< mp_fold<mp_list<mp_quote<F>...>, mp_list<T...>, detail::mp_compose_helper> >; | ||
|  | }; | ||
|  | 
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|  | #endif
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|  | 
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|  | template<class... Q> struct mp_compose_q | ||
|  | { | ||
|  |     template<class... T> using fn = mp_front< mp_fold<mp_list<Q...>, mp_list<T...>, detail::mp_compose_helper> >; | ||
|  | }; | ||
|  | 
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|  | } // namespace mp11
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|  | } // namespace boost
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|  | 
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|  | #endif // #ifndef BOOST_MP11_UTILITY_HPP_INCLUDED
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