Alias IntrusivePtr.WeakType
Weak pointer
IntrusivePtr
is a smart pointer that holds a non-owning ("weak") reference to an object that is managed by IntrusivePtr
.
It must be converted to IntrusivePtr
in order to access the referenced object.
IntrusivePtr
models temporary ownership: when an object needs to be accessed only if it exists, and it may be deleted at any time by someone else,
IntrusivePtr
is used to track the object, and it is converted to IntrusivePtr
to assume temporary ownership.
If the original IntrusivePtr
is destroyed at this time, the object's lifetime is extended until the temporary IntrusivePtr
is destroyed as well.
Another use for IntrusivePtr
is to break reference cycles formed by objects managed by IntrusivePtr
.
If such cycle is orphaned (i,e. there are no outside shared pointers into the cycle), the IntrusivePtr
reference counts cannot reach zero and the memory is leaked.
To prevent this, one of the pointers in the cycle can be made weak.