Returns None if the pointer is null, or else returns a shared reference to the value wrapped in Some. If the value may be uninitialized, [as_uninit_ref] must be used instead.

Safety

When calling this method, you have to ensure that either the pointer is null or the pointer is convertible to a reference.

Panics during const evaluation

This method will panic during const evaluation if the pointer cannot be determined to be null or not. See [is_null] for more information.

Null-unchecked version

If you are sure the pointer can never be null and are looking for some kind of as_ref_unchecked that returns the &T instead of Option<&T>, know that you can dereference the pointer directly.