tvl-depot/absl/flags/declare.h
Abseil Team 564001ae50 Export of internal Abseil changes
--
5448463d79c8473d29b6aae62359eaec09e517b0 by Greg Falcon <gfalcon@google.com>:

Rename absl_types_options.h to absl_alternate_options.h, to reflect that we are testing more than just types with this file.

PiperOrigin-RevId: 289099882

--
8008a5662d1b27c4ea442575405eb0538f63a636 by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 289097666

--
0e9398fae540bdb7dd752245b83456f3784c50ca by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 288985613
GitOrigin-RevId: 5448463d79c8473d29b6aae62359eaec09e517b0
Change-Id: I5bc1ee156294793cacf3acbc447c0ea27ce8af4f
2020-01-10 13:37:41 -05:00

66 lines
2.1 KiB
C++

//
// 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"
#include "absl/strings/string_view.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_