MPD  0.20.15
ScopeExit.hxx
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29 
30 #ifndef SCOPE_EXIT_HXX
31 #define SCOPE_EXIT_HXX
32 
33 #include "Compiler.h"
34 
35 #include <utility>
36 
40 template<typename F>
41 class ScopeExitGuard : F {
42  bool enabled = true;
43 
44 public:
45  explicit ScopeExitGuard(F &&f):F(std::forward<F>(f)) {}
46 
48  :F(std::move(src)), enabled(src.enabled) {
49  src.enabled = false;
50  }
51 
53  if (enabled)
54  F::operator()();
55  }
56 
57  ScopeExitGuard(const ScopeExitGuard &) = delete;
58  ScopeExitGuard &operator=(const ScopeExitGuard &) = delete;
59 };
60 
64 struct ScopeExitTag {
65  /* this operator is a trick so we don't need to close
66  parantheses at the end of the expression AtScopeExit()
67  call */
68  template<typename F>
70  return ScopeExitGuard<F>(std::forward<F>(f));
71  }
72 };
73 
74 #define ScopeExitCat(a, b) a ## b
75 #define ScopeExitName(line) ScopeExitCat(at_scope_exit_, line)
76 
87 #define AtScopeExit(...) auto ScopeExitName(__LINE__) = ScopeExitTag() + [__VA_ARGS__]()
88 
89 #endif
ScopeExitGuard & operator=(const ScopeExitGuard &)=delete
ScopeExitGuard(ScopeExitGuard &&src)
Definition: ScopeExit.hxx:47
Internal class.
Definition: ScopeExit.hxx:64
Internal class.
Definition: ScopeExit.hxx:41
ScopeExitGuard(F &&f)
Definition: ScopeExit.hxx:45
ScopeExitGuard< F > operator+(F &&f)
Definition: ScopeExit.hxx:69