LeechCraft  0.6.70-13729-g7046a9d2a7
Modular cross-platform feature rich live environment.
util.h
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29 
30 #pragma once
31 
32 #include <memory>
33 #include <functional>
34 #include <stdexcept>
35 
36 namespace LC
37 {
38 namespace Util
39 {
40  namespace detail
41  {
42  using DefaultScopeGuardDeleter = std::function<void ()>;
43 
44  class [[nodiscard]] SharedScopeGuard
45  {
46  std::shared_ptr<void> Guard_;
47  public:
48  template<typename F>
49  SharedScopeGuard (const F& f)
50  : Guard_ { nullptr, [f] (void*) { f (); } }
51  {
52  }
53 
54  SharedScopeGuard () = delete;
55 
56  SharedScopeGuard (const SharedScopeGuard&) = default;
57  SharedScopeGuard (SharedScopeGuard&&) = default;
58 
59  SharedScopeGuard& operator= (const SharedScopeGuard&) = default;
60  SharedScopeGuard& operator= (SharedScopeGuard&&) = default;
61  };
62 
63  template<typename F>
64  class [[nodiscard]] ScopeGuard
65  {
66  F F_;
67  bool Perform_ = true;
68  public:
69  ScopeGuard () noexcept
70  : F_ {}
71  , Perform_ { false }
72  {
73  }
74 
75  ScopeGuard (const F& f) noexcept
76  : F_ { f }
77  {
78  }
79 
80  ScopeGuard (const ScopeGuard&) = delete;
81  ScopeGuard& operator= (const ScopeGuard&) = delete;
82 
83  ScopeGuard& operator= (ScopeGuard&& other)
84  {
85  if (Perform_)
86  F_ ();
87 
88  F_ = other.F_;
89  Perform_ = other.Perform_;
90  other.Perform_ = false;
91  return *this;
92  }
93 
94  ScopeGuard (ScopeGuard&& other) noexcept
95  : F_ { other.F_ }
96  , Perform_ { other.Perform_ }
97  {
98  other.Perform_ = false;
99  }
100 
102  {
103  if (Perform_)
104  F_ ();
105  }
106 
107  void Dismiss () noexcept
108  {
109  Perform_ = false;
110  }
111 
113  {
114  Dismiss ();
116  }
117 
119  {
120  return EraseType ();
121  }
122 
124  {
125  if (!Perform_)
126  throw std::logic_error { "this scope guard has already been converted to a shared one" };
127 
128  Perform_ = false;
129  return { F_ };
130  }
131  };
132  }
133 
135 
156  template<typename F>
157  [[nodiscard]] detail::ScopeGuard<F> MakeScopeGuard (const F& f)
158  {
159  return { f };
160  }
161 }
162 }
void Dismiss() noexcept
Definition: util.h:107
ScopeGuard< DefaultScopeGuardDeleter > EraseType()
Definition: util.h:112
constexpr detail::ExprTree< detail::ExprType::LeafStaticPlaceholder, detail::MemberPtrs< Ptr > > f
Definition: oral.h:955
ScopeGuard() noexcept
Definition: util.h:69
SharedScopeGuard Shared()
Definition: util.h:123
std::function< void()> DefaultScopeGuardDeleter
Definition: util.h:42
detail::ScopeGuard< F > MakeScopeGuard(const F &f)
Returns an object performing passed function on scope exit.
Definition: util.h:157
ScopeGuard(const F &f) noexcept
Definition: util.h:75
ScopeGuard(ScopeGuard &&other) noexcept
Definition: util.h:94
Definition: constants.h:35