Porn Shared

std::shared_ptr is a smart pointer that retains shared ownership of an object through a pointer. Several shared_ptr objects may own the same object. The object is destroyed and its memory deallocated when either of the following happens:

The constructors of std::shared_ptr detect the presence of an unambiguous and accessible (i.e. public inheritance is mandatory) enable_shared_from_this base and assign the newly created std::shared_ptr to weak_this if not already owned by a live std::shared_ptr.

8. The aliasing constructor: constructs a shared_ptr which shares ownership information with the initial value of r, but holds an unrelated and unmanaged pointer ptr. If this shared_ptr is the last of the group to go out of scope, it will call the stored deleter for the object originally managed by r. However, calling get () on this shared_ptr will always return a copy of ptr. It is the ...

Exceptions If shared_from_this is called on an object that is not previously shared by std::shared_ptr, std::bad_weak_ptr is thrown by the std::shared_ptr constructor.

std::shared_ptr(new T(args...)) performs at least two allocations (one for the object T and one for the control block of the shared pointer), while std::make_shared typically performs only one allocation (the standard recommends, but does not require this; all known implementations do this). If any std::weak_ptr references the control block created by std::make_shared after the lifetime ...

Replaces the managed object with an object pointed to by ptr. Optional deleter d can be supplied, which is later used to destroy the new object when no shared_ptr objects own it. By default, delete expression is used as deleter. Proper delete expression corresponding to the supplied type is always selected, this is the reason why the function is implemented as template using a separate ...