xref: /aosp_15_r20/external/google-fruit/include/fruit/impl/meta/fold.h (revision a65addddcf69f38db5b288d787b6b7571a57bb8f) 
1*a65addddSAndroid Build Coastguard Worker /*
2*a65addddSAndroid Build Coastguard Worker  * Copyright 2014 Google Inc. All rights reserved.
3*a65addddSAndroid Build Coastguard Worker  *
4*a65addddSAndroid Build Coastguard Worker  * Licensed under the Apache License, Version 2.0 (the "License");
5*a65addddSAndroid Build Coastguard Worker  * you may not use this file except in compliance with the License.
6*a65addddSAndroid Build Coastguard Worker  * You may obtain a copy of the License at
7*a65addddSAndroid Build Coastguard Worker  *
8*a65addddSAndroid Build Coastguard Worker  *     http://www.apache.org/licenses/LICENSE-2.0
9*a65addddSAndroid Build Coastguard Worker  *
10*a65addddSAndroid Build Coastguard Worker  * Unless required by applicable law or agreed to in writing, software
11*a65addddSAndroid Build Coastguard Worker  * distributed under the License is distributed on an "AS IS" BASIS,
12*a65addddSAndroid Build Coastguard Worker  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13*a65addddSAndroid Build Coastguard Worker  * See the License for the specific language governing permissions and
14*a65addddSAndroid Build Coastguard Worker  * limitations under the License.
15*a65addddSAndroid Build Coastguard Worker  */
16*a65addddSAndroid Build Coastguard Worker 
17*a65addddSAndroid Build Coastguard Worker #ifndef FRUIT_META_FOLD_H
18*a65addddSAndroid Build Coastguard Worker #define FRUIT_META_FOLD_H
19*a65addddSAndroid Build Coastguard Worker 
20*a65addddSAndroid Build Coastguard Worker #include <functional>
21*a65addddSAndroid Build Coastguard Worker 
22*a65addddSAndroid Build Coastguard Worker namespace fruit {
23*a65addddSAndroid Build Coastguard Worker namespace impl {
24*a65addddSAndroid Build Coastguard Worker namespace meta {
25*a65addddSAndroid Build Coastguard Worker 
26*a65addddSAndroid Build Coastguard Worker struct Fold {
27*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue, typename... Types>
28*a65addddSAndroid Build Coastguard Worker   struct apply;
29*a65addddSAndroid Build Coastguard Worker 
30*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue>
31*a65addddSAndroid Build Coastguard Worker   struct apply<F, InitialValue> {
32*a65addddSAndroid Build Coastguard Worker     using type = InitialValue;
33*a65addddSAndroid Build Coastguard Worker   };
34*a65addddSAndroid Build Coastguard Worker 
35*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue, typename T0>
36*a65addddSAndroid Build Coastguard Worker   struct apply<F, InitialValue, T0> {
37*a65addddSAndroid Build Coastguard Worker     using type = typename F::template apply<InitialValue, T0>::type;
38*a65addddSAndroid Build Coastguard Worker   };
39*a65addddSAndroid Build Coastguard Worker 
40*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue, typename T0, typename T1>
41*a65addddSAndroid Build Coastguard Worker   struct apply<F, InitialValue, T0, T1> {
42*a65addddSAndroid Build Coastguard Worker     using type =
43*a65addddSAndroid Build Coastguard Worker         typename F::template apply<typename DoEval<typename F::template apply<InitialValue, T0>::type>::type, T1>::type;
44*a65addddSAndroid Build Coastguard Worker   };
45*a65addddSAndroid Build Coastguard Worker 
46*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue, typename T0, typename T1, typename T2>
47*a65addddSAndroid Build Coastguard Worker   struct apply<F, InitialValue, T0, T1, T2> {
48*a65addddSAndroid Build Coastguard Worker     using type = typename F::template apply<
49*a65addddSAndroid Build Coastguard Worker         typename DoEval<typename F::template apply<
50*a65addddSAndroid Build Coastguard Worker             typename DoEval<typename F::template apply<InitialValue, T0>::type>::type, T1>::type>::type,
51*a65addddSAndroid Build Coastguard Worker         T2>::type;
52*a65addddSAndroid Build Coastguard Worker   };
53*a65addddSAndroid Build Coastguard Worker 
54*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue, typename T0, typename T1, typename T2, typename T3>
55*a65addddSAndroid Build Coastguard Worker   struct apply<F, InitialValue, T0, T1, T2, T3> {
56*a65addddSAndroid Build Coastguard Worker     using type = typename F::template apply<
57*a65addddSAndroid Build Coastguard Worker         typename DoEval<typename F::template apply<
58*a65addddSAndroid Build Coastguard Worker             typename DoEval<typename F::template apply<
59*a65addddSAndroid Build Coastguard Worker                 typename DoEval<typename F::template apply<InitialValue, T0>::type>::type, T1>::type>::type,
60*a65addddSAndroid Build Coastguard Worker             T2>::type>::type,
61*a65addddSAndroid Build Coastguard Worker         T3>::type;
62*a65addddSAndroid Build Coastguard Worker   };
63*a65addddSAndroid Build Coastguard Worker 
64*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue, typename T0, typename T1, typename T2, typename T3, typename T4>
65*a65addddSAndroid Build Coastguard Worker   struct apply<F, InitialValue, T0, T1, T2, T3, T4> {
66*a65addddSAndroid Build Coastguard Worker     using type = typename F::template apply<
67*a65addddSAndroid Build Coastguard Worker         typename DoEval<typename F::template apply<
68*a65addddSAndroid Build Coastguard Worker             typename DoEval<typename F::template apply<
69*a65addddSAndroid Build Coastguard Worker                 typename DoEval<typename F::template apply<
70*a65addddSAndroid Build Coastguard Worker                     typename DoEval<typename F::template apply<InitialValue, T0>::type>::type, T1>::type>::type,
71*a65addddSAndroid Build Coastguard Worker                 T2>::type>::type,
72*a65addddSAndroid Build Coastguard Worker             T3>::type>::type,
73*a65addddSAndroid Build Coastguard Worker         T4>::type;
74*a65addddSAndroid Build Coastguard Worker   };
75*a65addddSAndroid Build Coastguard Worker 
76*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue, typename T0, typename T1, typename T2, typename T3, typename T4,
77*a65addddSAndroid Build Coastguard Worker             typename... Types>
78*a65addddSAndroid Build Coastguard Worker   struct apply<F, InitialValue, T0, T1, T2, T3, T4, Types...> {
79*a65addddSAndroid Build Coastguard Worker     using type = Fold(
80*a65addddSAndroid Build Coastguard Worker         F, typename F::template apply<
81*a65addddSAndroid Build Coastguard Worker                typename DoEval<typename F::template apply<
82*a65addddSAndroid Build Coastguard Worker                    typename DoEval<typename F::template apply<
83*a65addddSAndroid Build Coastguard Worker                        typename DoEval<typename F::template apply<
84*a65addddSAndroid Build Coastguard Worker                            typename DoEval<typename F::template apply<InitialValue, T0>::type>::type, T1>::type>::type,
85*a65addddSAndroid Build Coastguard Worker                        T2>::type>::type,
86*a65addddSAndroid Build Coastguard Worker                    T3>::type>::type,
87*a65addddSAndroid Build Coastguard Worker                T4>::type,
88*a65addddSAndroid Build Coastguard Worker         Types...);
89*a65addddSAndroid Build Coastguard Worker   };
90*a65addddSAndroid Build Coastguard Worker 
91*a65addddSAndroid Build Coastguard Worker   // Optimized specialization, processing 10 values at a time.
92*a65addddSAndroid Build Coastguard Worker   template <typename F, typename InitialValue, typename T0, typename T1, typename T2, typename T3, typename T4,
93*a65addddSAndroid Build Coastguard Worker             typename T5, typename T6, typename T7, typename T8, typename T9, typename... Types>
94*a65addddSAndroid Build Coastguard Worker   struct apply<F, InitialValue, T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, Types...> {
95*a65addddSAndroid Build Coastguard Worker     using type = Fold(
96*a65addddSAndroid Build Coastguard Worker         F,
97*a65addddSAndroid Build Coastguard Worker         typename F::template apply<
98*a65addddSAndroid Build Coastguard Worker             typename DoEval<typename F::template apply<
99*a65addddSAndroid Build Coastguard Worker                 typename DoEval<typename F::template apply<
100*a65addddSAndroid Build Coastguard Worker                     typename DoEval<typename F::template apply<
101*a65addddSAndroid Build Coastguard Worker                         typename DoEval<typename F::template apply<
102*a65addddSAndroid Build Coastguard Worker                             typename DoEval<typename F::template apply<
103*a65addddSAndroid Build Coastguard Worker                                 typename DoEval<typename F::template apply<
104*a65addddSAndroid Build Coastguard Worker                                     typename DoEval<typename F::template apply<
105*a65addddSAndroid Build Coastguard Worker                                         typename DoEval<typename F::template apply<
106*a65addddSAndroid Build Coastguard Worker                                             typename DoEval<typename F::template apply<InitialValue, T0>::type>::type,
107*a65addddSAndroid Build Coastguard Worker                                             T1>::type>::type,
108*a65addddSAndroid Build Coastguard Worker                                         T2>::type>::type,
109*a65addddSAndroid Build Coastguard Worker                                     T3>::type>::type,
110*a65addddSAndroid Build Coastguard Worker                                 T4>::type>::type,
111*a65addddSAndroid Build Coastguard Worker                             T5>::type>::type,
112*a65addddSAndroid Build Coastguard Worker                         T6>::type>::type,
113*a65addddSAndroid Build Coastguard Worker                     T7>::type>::type,
114*a65addddSAndroid Build Coastguard Worker                 T8>::type>::type,
115*a65addddSAndroid Build Coastguard Worker             T9>::type,
116*a65addddSAndroid Build Coastguard Worker         Types...);
117*a65addddSAndroid Build Coastguard Worker   };
118*a65addddSAndroid Build Coastguard Worker };
119*a65addddSAndroid Build Coastguard Worker 
120*a65addddSAndroid Build Coastguard Worker } // namespace meta
121*a65addddSAndroid Build Coastguard Worker } // namespace impl
122*a65addddSAndroid Build Coastguard Worker } // namespace fruit
123*a65addddSAndroid Build Coastguard Worker 
124*a65addddSAndroid Build Coastguard Worker #endif // FRUIT_META_FOLD_H
125