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Diffstat (limited to 'third_party/abseil_cpp/absl/base/internal/invoke.h')
| -rw-r--r-- | third_party/abseil_cpp/absl/base/internal/invoke.h | 187 |
1 files changed, 0 insertions, 187 deletions
diff --git a/third_party/abseil_cpp/absl/base/internal/invoke.h b/third_party/abseil_cpp/absl/base/internal/invoke.h deleted file mode 100644 index 5c71f328234f..000000000000 --- a/third_party/abseil_cpp/absl/base/internal/invoke.h +++ /dev/null @@ -1,187 +0,0 @@ -// Copyright 2017 The Abseil Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// https://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. -// -// absl::base_internal::invoke(f, args...) is an implementation of -// INVOKE(f, args...) from section [func.require] of the C++ standard. -// -// [func.require] -// Define INVOKE (f, t1, t2, ..., tN) as follows: -// 1. (t1.*f)(t2, ..., tN) when f is a pointer to a member function of a class T -// and t1 is an object of type T or a reference to an object of type T or a -// reference to an object of a type derived from T; -// 2. ((*t1).*f)(t2, ..., tN) when f is a pointer to a member function of a -// class T and t1 is not one of the types described in the previous item; -// 3. t1.*f when N == 1 and f is a pointer to member data of a class T and t1 is -// an object of type T or a reference to an object of type T or a reference -// to an object of a type derived from T; -// 4. (*t1).*f when N == 1 and f is a pointer to member data of a class T and t1 -// is not one of the types described in the previous item; -// 5. f(t1, t2, ..., tN) in all other cases. -// -// The implementation is SFINAE-friendly: substitution failure within invoke() -// isn't an error. - -#ifndef ABSL_BASE_INTERNAL_INVOKE_H_ -#define ABSL_BASE_INTERNAL_INVOKE_H_ - -#include <algorithm> -#include <type_traits> -#include <utility> - -#include "absl/meta/type_traits.h" - -// The following code is internal implementation detail. See the comment at the -// top of this file for the API documentation. - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace base_internal { - -// The five classes below each implement one of the clauses from the definition -// of INVOKE. The inner class template Accept<F, Args...> checks whether the -// clause is applicable; static function template Invoke(f, args...) does the -// invocation. -// -// By separating the clause selection logic from invocation we make sure that -// Invoke() does exactly what the standard says. - -template <typename Derived> -struct StrippedAccept { - template <typename... Args> - struct Accept : Derived::template AcceptImpl<typename std::remove_cv< - typename std::remove_reference<Args>::type>::type...> {}; -}; - -// (t1.*f)(t2, ..., tN) when f is a pointer to a member function of a class T -// and t1 is an object of type T or a reference to an object of type T or a -// reference to an object of a type derived from T. -struct MemFunAndRef : StrippedAccept<MemFunAndRef> { - template <typename... Args> - struct AcceptImpl : std::false_type {}; - - template <typename MemFunType, typename C, typename Obj, typename... Args> - struct AcceptImpl<MemFunType C::*, Obj, Args...> - : std::integral_constant<bool, std::is_base_of<C, Obj>::value && - absl::is_function<MemFunType>::value> { - }; - - template <typename MemFun, typename Obj, typename... Args> - static decltype((std::declval<Obj>().* - std::declval<MemFun>())(std::declval<Args>()...)) - Invoke(MemFun&& mem_fun, Obj&& obj, Args&&... args) { - return (std::forward<Obj>(obj).* - std::forward<MemFun>(mem_fun))(std::forward<Args>(args)...); - } -}; - -// ((*t1).*f)(t2, ..., tN) when f is a pointer to a member function of a -// class T and t1 is not one of the types described in the previous item. -struct MemFunAndPtr : StrippedAccept<MemFunAndPtr> { - template <typename... Args> - struct AcceptImpl : std::false_type {}; - - template <typename MemFunType, typename C, typename Ptr, typename... Args> - struct AcceptImpl<MemFunType C::*, Ptr, Args...> - : std::integral_constant<bool, !std::is_base_of<C, Ptr>::value && - absl::is_function<MemFunType>::value> { - }; - - template <typename MemFun, typename Ptr, typename... Args> - static decltype(((*std::declval<Ptr>()).* - std::declval<MemFun>())(std::declval<Args>()...)) - Invoke(MemFun&& mem_fun, Ptr&& ptr, Args&&... args) { - return ((*std::forward<Ptr>(ptr)).* - std::forward<MemFun>(mem_fun))(std::forward<Args>(args)...); - } -}; - -// t1.*f when N == 1 and f is a pointer to member data of a class T and t1 is -// an object of type T or a reference to an object of type T or a reference -// to an object of a type derived from T. -struct DataMemAndRef : StrippedAccept<DataMemAndRef> { - template <typename... Args> - struct AcceptImpl : std::false_type {}; - - template <typename R, typename C, typename Obj> - struct AcceptImpl<R C::*, Obj> - : std::integral_constant<bool, std::is_base_of<C, Obj>::value && - !absl::is_function<R>::value> {}; - - template <typename DataMem, typename Ref> - static decltype(std::declval<Ref>().*std::declval<DataMem>()) Invoke( - DataMem&& data_mem, Ref&& ref) { - return std::forward<Ref>(ref).*std::forward<DataMem>(data_mem); - } -}; - -// (*t1).*f when N == 1 and f is a pointer to member data of a class T and t1 -// is not one of the types described in the previous item. -struct DataMemAndPtr : StrippedAccept<DataMemAndPtr> { - template <typename... Args> - struct AcceptImpl : std::false_type {}; - - template <typename R, typename C, typename Ptr> - struct AcceptImpl<R C::*, Ptr> - : std::integral_constant<bool, !std::is_base_of<C, Ptr>::value && - !absl::is_function<R>::value> {}; - - template <typename DataMem, typename Ptr> - static decltype((*std::declval<Ptr>()).*std::declval<DataMem>()) Invoke( - DataMem&& data_mem, Ptr&& ptr) { - return (*std::forward<Ptr>(ptr)).*std::forward<DataMem>(data_mem); - } -}; - -// f(t1, t2, ..., tN) in all other cases. -struct Callable { - // Callable doesn't have Accept because it's the last clause that gets picked - // when none of the previous clauses are applicable. - template <typename F, typename... Args> - static decltype(std::declval<F>()(std::declval<Args>()...)) Invoke( - F&& f, Args&&... args) { - return std::forward<F>(f)(std::forward<Args>(args)...); - } -}; - -// Resolves to the first matching clause. -template <typename... Args> -struct Invoker { - typedef typename std::conditional< - MemFunAndRef::Accept<Args...>::value, MemFunAndRef, - typename std::conditional< - MemFunAndPtr::Accept<Args...>::value, MemFunAndPtr, - typename std::conditional< - DataMemAndRef::Accept<Args...>::value, DataMemAndRef, - typename std::conditional<DataMemAndPtr::Accept<Args...>::value, - DataMemAndPtr, Callable>::type>::type>:: - type>::type type; -}; - -// The result type of Invoke<F, Args...>. -template <typename F, typename... Args> -using invoke_result_t = decltype(Invoker<F, Args...>::type::Invoke( - std::declval<F>(), std::declval<Args>()...)); - -// Invoke(f, args...) is an implementation of INVOKE(f, args...) from section -// [func.require] of the C++ standard. -template <typename F, typename... Args> -invoke_result_t<F, Args...> invoke(F&& f, Args&&... args) { - return Invoker<F, Args...>::type::Invoke(std::forward<F>(f), - std::forward<Args>(args)...); -} -} // namespace base_internal -ABSL_NAMESPACE_END -} // namespace absl - -#endif // ABSL_BASE_INTERNAL_INVOKE_H_ |