refcnt_ptr.md

Header <intrusive_shared_ptr/refcnt_ptr.h>

• Class isptr::refcnt_ptr
• Namespace methods

Class isptr::refcnt_ptr

template<class T>
using refcnt_ptr = intrusive_shared_ptr<T, typename T::refcnt_ptr_traits>;

refcnt_ptr is a specialization of intrusive_shared_ptr for a common case where you fully control the pointee's class and can provide traits as a nested type named refcnt_ptr_traits. A ref_counted base class provides such an implementation so you can easily use ref_counted derived classes with refcnt_ptr.

Namespace methods

• template<class T> constexpr refcnt_ptr<T> refcnt_retain(T * ptr) noexcept. Creates refcnt_ptr from a raw pointer and increments the reference count.
• template<class T> constexpr refcnt_ptr<T> refcnt_attach(T * ptr) noexcept. Creates refcnt_ptr from a raw pointer without incrementing the reference count.
• template<class T, class... Args> refcnt_ptr<T> make_refcnt(Args &&... args). A convenience function that creates an instance of T via new and forwards the arguments to its constructor. Equivalent to refcnt_attach(new T(args)).
• template<class T> refcnt_ptr<typename T::weak_value_type> weak_cast(const refcnt_ptr<T> & src) and
  template<class T> refcnt_ptr<const typename T::weak_value_type> weak_cast(const refcnt_ptr<const T> & src).
  If T provides a type called weak_value_type and a method get_weak_ptr() it is assumed to support weak references. These functions provide a convenient "cast" conversion from a strong to a weak pointer wrapping the call to get_weak_ptr().
• template<class T> refcnt_ptr<typename T::strong_value_type> strong_cast(const refcnt_ptr<T> & src) noexcept and
  template<class T> refcnt_ptr<const typename T::strong_value_type> strong_cast(const refcnt_ptr<const T> & src) noexcept
  If T provides a type called strong_value_type and a method lock() it is assumed to be a weak reference. These functions provide a convenient "cast" conversion from a weak to a strong pointer wrapping the call to lock().