ceph/src/boost/boost/mp11/bind.hpp

   1 #ifndef BOOST_MP11_BIND_HPP_INCLUDED
   2 #define BOOST_MP11_BIND_HPP_INCLUDED
   3
   4 //  Copyright 2017, 2018 Peter Dimov.
   5 //
   6 //  Distributed under the Boost Software License, Version 1.0.
   7 //
   8 //  See accompanying file LICENSE_1_0.txt or copy at
   9 //  http://www.boost.org/LICENSE_1_0.txt
  10
  11 #include <boost/mp11/algorithm.hpp>
  12 #include <boost/mp11/utility.hpp>
  13 #include <cstddef>
  14
  15 namespace boost
  16 {
  17 namespace mp11
  18 {
  19
  20 // mp_bind_front
  21 template<template<class...> class F, class... T> struct mp_bind_front
  22 {
  23     // the indirection through mp_defer works around the language inability
  24     // to expand U... into a fixed parameter list of an alias template
  25
  26     template<class... U> using fn = typename mp_defer<F, T..., U...>::type;
  27 };
  28
  29 template<class Q, class... T> using mp_bind_front_q = mp_bind_front<Q::template fn, T...>;
  30
  31 // mp_bind_back
  32 template<template<class...> class F, class... T> struct mp_bind_back
  33 {
  34     template<class... U> using fn = typename mp_defer<F, U..., T...>::type;
  35 };
  36
  37 template<class Q, class... T> using mp_bind_back_q = mp_bind_back<Q::template fn, T...>;
  38
  39 // mp_arg
  40 template<std::size_t I> struct mp_arg
  41 {
  42     template<class... T> using fn = mp_at_c<mp_list<T...>, I>;
  43 };
  44
  45 using _1 = mp_arg<0>;
  46 using _2 = mp_arg<1>;
  47 using _3 = mp_arg<2>;
  48 using _4 = mp_arg<3>;
  49 using _5 = mp_arg<4>;
  50 using _6 = mp_arg<5>;
  51 using _7 = mp_arg<6>;
  52 using _8 = mp_arg<7>;
  53 using _9 = mp_arg<8>;
  54
  55 // mp_bind
  56 template<template<class...> class F, class... T> struct mp_bind;
  57
  58 namespace detail
  59 {
  60
  61 template<class V, class... T> struct eval_bound_arg
  62 {
  63     using type = V;
  64 };
  65
  66 template<std::size_t I, class... T> struct eval_bound_arg<mp_arg<I>, T...>
  67 {
  68     using type = typename mp_arg<I>::template fn<T...>;
  69 };
  70
  71 template<template<class...> class F, class... U, class... T> struct eval_bound_arg<mp_bind<F, U...>, T...>
  72 {
  73     using type = typename mp_bind<F, U...>::template fn<T...>;
  74 };
  75
  76 template<template<class...> class F, class... U, class... T> struct eval_bound_arg<mp_bind_front<F, U...>, T...>
  77 {
  78     using type = typename mp_bind_front<F, U...>::template fn<T...>;
  79 };
  80
  81 template<template<class...> class F, class... U, class... T> struct eval_bound_arg<mp_bind_back<F, U...>, T...>
  82 {
  83     using type = typename mp_bind_back<F, U...>::template fn<T...>;
  84 };
  85
  86 } // namespace detail
  87
  88 template<template<class...> class F, class... T> struct mp_bind
  89 {
  90 #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, == 1915 )
  91 private:
  92
  93     template<class... U> struct _f { using type = F<typename detail::eval_bound_arg<T, U...>::type...>; };
  94
  95 public:
  96
  97     template<class... U> using fn = typename _f<U...>::type;
  98
  99 #else
 100
 101     template<class... U> using fn = F<typename detail::eval_bound_arg<T, U...>::type...>;
 102
 103 #endif
 104 };
 105
 106 template<class Q, class... T> using mp_bind_q = mp_bind<Q::template fn, T...>;
 107
 108 } // namespace mp11
 109 } // namespace boost
 110
 111 #endif // #ifndef BOOST_MP11_BIND_HPP_INCLUDED