1 /* 2 * Copyright 2014 Google Inc. All rights reserved. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef FRUIT_META_ALGOS_H 18 #define FRUIT_META_ALGOS_H 19 20 #include <fruit/impl/fruit-config.h> 21 #include <fruit/impl/meta/immutable_map.h> 22 23 namespace fruit { 24 namespace impl { 25 namespace meta { 26 27 // We need a different (slower) implementation to workaround a Clang bug: 28 // https://llvm.org/bugs/show_bug.cgi?id=25669 29 // TODO: remove this once that bug is fixed (for the appropriate Clang versions). 30 #if FRUIT_HAS_CLANG_ARBITRARY_OVERLOAD_RESOLUTION_BUG 31 32 struct HasDuplicatesHelper { 33 template <typename... Types> 34 struct apply { 35 using type = Bool<false>; 36 }; 37 38 template <typename Type, typename... Types> 39 struct apply<Type, Types...> { 40 using type = Or(StaticOr<std::is_same<Type, Types>::value...>, Id<HasDuplicatesHelper(Types...)>); 41 }; 42 }; 43 44 struct HasDuplicates { 45 template <typename V> 46 struct apply; 47 48 template <typename... Types> 49 struct apply<Vector<Types...>> { 50 using type = HasDuplicatesHelper(Types...); 51 }; 52 }; 53 54 #else // !FRUIT_HAS_CLANG_ARBITRARY_OVERLOAD_RESOLUTION_BUG 55 56 // Checks if the given Vector has duplicated types. 57 struct HasDuplicates { 58 template <typename V> 59 struct apply; 60 61 template <typename... Types> 62 struct apply<Vector<Types...>> { 63 using M = VectorsToImmutableMap(Vector<Types...>, GenerateIntSequence(Int<sizeof...(Types)>)); 64 using type = Not(StaticAnd<Eval<ImmutableMapContainsKey(M, Types)>::value...>); 65 }; 66 }; 67 68 #endif // FRUIT_HAS_CLANG_ARBITRARY_OVERLOAD_RESOLUTION_BUG 69 70 } // namespace meta 71 } // namespace impl 72 } // namespace fruit 73 74 #endif // FRUIT_META_ALGOS_H 75