Abseil Common Libraries (C++) (grcp 依赖)
https://abseil.io/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
65 lines
2.0 KiB
65 lines
2.0 KiB
// |
|
// Copyright 2019 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. |
|
// |
|
// ----------------------------------------------------------------------------- |
|
// File: declare.h |
|
// ----------------------------------------------------------------------------- |
|
// |
|
// This file defines the ABSL_DECLARE_FLAG macro, allowing you to declare an |
|
// `absl::Flag` for use within a translation unit. You should place this |
|
// declaration within the header file associated with the .cc file that defines |
|
// and owns the `Flag`. |
|
|
|
#ifndef ABSL_FLAGS_DECLARE_H_ |
|
#define ABSL_FLAGS_DECLARE_H_ |
|
|
|
#include "absl/base/config.h" |
|
|
|
namespace absl { |
|
ABSL_NAMESPACE_BEGIN |
|
namespace flags_internal { |
|
|
|
// absl::Flag<T> represents a flag of type 'T' created by ABSL_FLAG. |
|
template <typename T> |
|
class Flag; |
|
|
|
} // namespace flags_internal |
|
|
|
// Flag |
|
// |
|
// Forward declaration of the `absl::Flag` type for use in defining the macro. |
|
#if defined(_MSC_VER) && !defined(__clang__) |
|
template <typename T> |
|
class Flag; |
|
#else |
|
template <typename T> |
|
using Flag = flags_internal::Flag<T>; |
|
#endif |
|
|
|
ABSL_NAMESPACE_END |
|
} // namespace absl |
|
|
|
// ABSL_DECLARE_FLAG() |
|
// |
|
// This macro is a convenience for declaring use of an `absl::Flag` within a |
|
// translation unit. This macro should be used within a header file to |
|
// declare usage of the flag within any .cc file including that header file. |
|
// |
|
// The ABSL_DECLARE_FLAG(type, name) macro expands to: |
|
// |
|
// extern absl::Flag<type> FLAGS_name; |
|
#define ABSL_DECLARE_FLAG(type, name) extern ::absl::Flag<type> FLAGS_##name |
|
|
|
#endif // ABSL_FLAGS_DECLARE_H_
|
|
|