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 |
112 | |