libstdc++
cond_dealtor.hpp
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3 // Copyright (C) 2005-2022 Free Software Foundation, Inc.
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25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
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35 
36 /**
37  * @file detail/cond_dealtor.hpp
38  * Contains a conditional deallocator.
39  */
40 
41 #ifndef PB_DS_COND_DEALTOR_HPP
42 #define PB_DS_COND_DEALTOR_HPP
43 
45 
46 namespace __gnu_pbds
47 {
48  namespace detail
49  {
50  /// Conditional deallocate constructor argument.
51  template<typename Entry, typename _Alloc>
53  {
55 
56  public:
57  typedef typename alloc_traits::allocator_type entry_allocator;
58  typedef typename alloc_traits::pointer entry_pointer;
59 
60  cond_dealtor(entry_pointer p_e)
61  : m_p_e(p_e), m_no_action_destructor(false) { }
62 
63  ~cond_dealtor()
64  {
65  if (m_no_action_destructor)
66  return;
67  s_alloc.deallocate(m_p_e, 1);
68  }
69 
70  void
71  set_no_action()
72  { m_no_action_destructor = true; }
73 
74  private:
75  entry_pointer m_p_e;
76  bool m_no_action_destructor;
77  static entry_allocator s_alloc;
78  };
79 
80  template<typename Entry, class _Alloc>
81  typename cond_dealtor<Entry, _Alloc>::entry_allocator
83  } // namespace detail
84 } // namespace __gnu_pbds
85 
86 #endif // #ifndef PB_DS_COND_DEALTOR_HPP
GNU extensions for policy-based data structures for public use.
Conditional deallocate constructor argument.