pub struct ArcBorrow<'a, T: 'a>(_);
Arc”. This is a pointer to
a T that is known to have been allocated within an
This is equivalent in guarantees to
&Arc<T>, however it is
a bit more flexible. To obtain an
&Arc<T> you must have
Arc<T> instance somewhere pinned down until we’re done with it.
It’s also a direct pointer to
T, so using this involves less pointer-chasing
However, C++ code may hand us refcounted things as pointers to T directly,
so we have to conjure up a temporary
Arc on the stack each time.
ArcBorrow lets us deal with borrows of known-refcounted objects
without needing to worry about where the
For constructing from a reference known to be Arc-backed, e.g. if we obtain such a reference over FFI
ArcBorrows via pointer equality. Will only return
true if they come from the same allocation
Temporarily converts |self| into a bonafide Arc and exposes it to the provided callback. The refcount is not modified.
othervalues to be equal, and is used by