1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef BASE_CALLBACK_FORWARD_H_
6#define BASE_CALLBACK_FORWARD_H_
7
8namespace base {
9namespace internal {
10
11// CopyMode is used to control the copyablity of a Callback.
12// MoveOnly indicates the Callback is not copyable but movable, and Copyable
13// indicates it is copyable and movable.
14enum class CopyMode {
15  MoveOnly,
16  Copyable,
17};
18
19enum class RepeatMode {
20  Once,
21  Repeating,
22};
23
24}  // namespace internal
25
26template <typename Signature,
27          internal::CopyMode copy_mode = internal::CopyMode::Copyable,
28          internal::RepeatMode repeat_mode = internal::RepeatMode::Repeating>
29class Callback;
30
31// Syntactic sugar to make Callback<void()> easier to declare since it
32// will be used in a lot of APIs with delayed execution.
33using Closure = Callback<void()>;
34
35template <typename Signature>
36using OnceCallback = Callback<Signature,
37                              internal::CopyMode::MoveOnly,
38                              internal::RepeatMode::Once>;
39template <typename Signature>
40using RepeatingCallback = Callback<Signature,
41                                   internal::CopyMode::Copyable,
42                                   internal::RepeatMode::Repeating>;
43using OnceClosure = OnceCallback<void()>;
44using RepeatingClosure = RepeatingCallback<void()>;
45
46}  // namespace base
47
48#endif  // BASE_CALLBACK_FORWARD_H_
49