chromium/third_party/grpc/src/src/core/lib/gprpp/manual_constructor.h

//
//
// Copyright 2016 gRPC 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
//
//     http://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.
//
//

#ifndef GRPC_SRC_CORE_LIB_GPRPP_MANUAL_CONSTRUCTOR_H
#define GRPC_SRC_CORE_LIB_GPRPP_MANUAL_CONSTRUCTOR_H

// manually construct a region of memory with some type

#include <grpc/support/port_platform.h>

#include <stddef.h>

#include <type_traits>
#include <utility>

#include "src/core/lib/gprpp/construct_destruct.h"

namespace grpc_core {

// this contains templated helpers needed to implement the ManualConstructors
// in this file.
namespace manual_ctor_impl {

// is_one_of returns true it a class, Member, is present in a variadic list of
// classes, List.
template <class Member, class... List>
class is_one_of;

is_one_of<Member, Member, List...>;

is_one_of<Member, A, List...>;

is_one_of<Member>;

// max_size_of returns sizeof(Type) for the largest type in the variadic list
// of classes, Types.
template <class... Types>
class max_size_of;

max_size_of<A>;

max_size_of<A, B...>;

// max_size_of returns alignof(Type) for the largest type in the variadic list
// of classes, Types.
template <class... Types>
class max_align_of;

max_align_of<A>;

max_align_of<A, B...>;

}  // namespace manual_ctor_impl

template <typename Type>
class ManualConstructor { … };

}  // namespace grpc_core

#endif  // GRPC_SRC_CORE_LIB_GPRPP_MANUAL_CONSTRUCTOR_H